Metal swarf

Metal swarf, also known as chips or by other process-specific names (such as turnings, filings, or shavings), are pieces of metal that are the debris or waste resulting from machining or similar subtractive (material-removing) manufacturing processes. Metal swarf can be small particles (such as the gritty swarf from grinding metal) or long, stringy tendrils (such as the springy chips from turning tough metals).
Cutting hazards and safety precautions.
Cuts, splinters, punctures, airborne chips.
Chips can be extremely sharp, and this creates a safety problem, as they can cause serious injuries if not handled correctly. Depending on the composition of the material, it can persist in the environment for a long time before degrading. This, combined with the small size of some chips (e.g. those of brass or bronze), allows them to disperse widely by piggy-backing on soft materials and also to penetrate the skin as deep splinters.
It is standard training for machinists, and usually a standing workplace rule, to avoid handling swarf with bare hands. Similarly, it is also standard training for machinists, and usually a standing workplace rule, to minimize or entirely avoid handling swarf by blowing chips away with compressed air, but this practice can potentially damage the machine by causing chips to get jammed in and then embedded into the moving surfaces leading to degradation of the machine's precision. Alternatives to blowing chips away include vacuuming them away with an industrial vacuum (shop vacuum); gently washing them away with a coolant hose discharging at typical garden-hose pressures; or preventing their generation in the first place (for example, forming threads instead of cutting them). Some machine tool manuals proscribe these practices both for safety and for the preservation of way wipers and bearing seals.
It is not uncommon for chips flying off the cutter to be ejected with great force and to fly several metres. These flying chips present a hazard that is deflected with safety glasses, face shields, and other personal protective equipment, as well as the sheet-metal enclosures (and polycarbonate windows) that surround most commercial computer numerical control (CNC) machine tools.
Flammability.
Due to its high surface area, swarf composed of some reactive metals can be highly flammable. Caution should be exercised to avoid ignition sources when handling or storing swarf in loose form, especially swarf of pure magnesium, magnesium alloy, pure titanium, titanium alloy, iron, and non-stainless steel.
Swarf stored in piles or bins may also spontaneously combust, especially if the swarf is coated with cutting oil.
To extinguish swarf fires, a special fire extinguisher is needed, designed for fighting (metal) fires.
Toxicity.
Some common engineering materials such as beryllium are hazardous when finely divided and appropriate measures should be taken to prevent exposure.
Chip breaking.
Optimum cutting efficiencies often generate long spring-like swarf. This is hard to deal with as it is bulky and can clog the nozzle of a shop vac. Clean-up and disposal of this continuous-cutting swarf is made simpler by using a cutting tool with a chip-breaker. This results in denser, more manageable waste. Chip breaking tool geometry is generally designed to break the chip by having it curl back onto itself. This action produces many small spiral shaped rings instead of one long helical chip. "Number Nine" shaped chips or short swarf in general are preferred also because it helps prevent entangling the rotating machine.
Machine cleaning and chip handling.
Disposing of swarf is a tedious but necessary task. For ease of transport and handling, swarf may be compressed into "bricks", which greatly reduces associated problems with storing and cost; it also improves material handling for all concerned with its reclamation and recycling.
Recycling.
Metal swarf can usually be recycled, and this is the preferred method of disposal due to the environmental concerns regarding potential contamination with cutting fluid or tramp oil. The ideal way to remove these liquids is by the use of a centrifuge which will separate the fluids from the metal, allowing both to be reclaimed and prepared for further treatment. Small bundles of stainless steel or bronze swarf are sold as excellent scourers for dishwashing or cleaning encrustations of dirt. Recycling chips rather than putting them in the garbage stream (heading to landfilling or incineration) has various advantages:
Requirements.
Machine shops are typically required by the scrap collector to:


2001 J.League Cup

Statistics of J. League Cup, officially the 2001 J.League Yamazaki Nabisco Cup, in the 2001 season.
Overview.
It was contested by 28 teams, and Yokohama F. Marinos won the championship.
Results.
1st round.
The first legs were played on 4 April, and the second legs were played on 18 April. 12 teams from the Division 1 and all 12 teams from the Division 2 entered this round.

2nd round.
The first legs were played on 13 June, and the second legs were played on 20 June. The 4 remaining teams from the Division 1 entered this round.

Quarterfinals.
The first legs were played on 8 August, and the second legs were played from 22 to 29 August.

Semifinals.
The first legs were played on 26 September, and the second legs were played on 10 October.

Final.
Yokohama F. Marinos won the championship.


Powder bed and inkjet head 3D printing

Binder jet 3D printing, known variously as "Powder bed and inkjet" and "drop-on-powder" printing, is a rapid prototyping and additive manufacturing technology for making objects described by digital data such as a CAD file. Binder jetting is one of the seven categories of additive manufacturing processes according to ASTM and ISO.
History.
This technology was first developed at the Massachusetts Institute of Technology and patented in 1993. In 1996, the ExOne Company was granted an exclusive field-of-use patent for the technology, while Z Corporation, which was later acquired by 3D Systems, obtained a non-exclusive patent for use of the technology for metal casting purposes. The term "Three-Dimensional Printing" was trademarked by the research group at MIT, along with the abbreviation 3DP. As a result, the term "3D printing" originally referred uniquely to the binder jet printing process prior to gaining wider acceptance as a term referring to all additive manufacturing processes.
Description.
As in many other additive manufacturing processes the part to be printed is built up from many thin cross sections of the 3D model. An inkjet print head moves across a bed of powder, selectively depositing a liquid binding material. A thin layer of powder is spread across the completed section and the process is repeated with each layer adhering to the last.
When the model is complete, unbound powder is automatically and/or manually removed in a process called "de-powdering" and may be reused to some extent.
The de-powdered part could optionally be subjected to various infiltrants or other treatments to produce properties desired in the final part.
Materials.
In the original implementations, starch and gypsum plaster fill the powder bed, the liquid "binder" being mostly water to activate the plaster. The binder also includes dyes (for color printing), and additives to adjust viscosity, surface tension, and boiling point to match print head specifications. The resulting plaster parts typically lack "green strength" and require infiltration by melted wax, cyanoacrylate glue, epoxy, etc. before regular handling.
While not necessarily employing conventional inkjet technology, various other powder-binder combinations may be deployed to form objects by chemical or mechanical means. The resulting parts may then be subjected to different post-processing regimes, such as infiltration or bakeout. This may be done, for example, to eliminate the mechanical binder (e.g., by burning) and consolidate the core material (e.g., by melting), or to form a composite material blending the properties of powder and binder. Depending on the material, full color printing may or may not be an option. As of 2014, inventors and manufacturers have developed systems for forming objects from sand and calcium carbonate (forming a synthetic marble), acrylic powder and cyanoacrylate, ceramic powder and a liquid binder, sugar and water (for making candies), etc. One of the first commercially available products that incorporated the use of Graphene, was a powdered composite used in powder bed inkjet head 3D printing.
3D printing technology has a limited potential to vary material properties in a single build, but is generally limited by the use of a common core material. In the original Z Corporation systems, cross-sections are typically printed with solid outlines (forming a solid shell) and a lower-density interior pattern to speed printing and ensure dimensional stability as the part cures.
Characteristics.
In addition to volumetric color by use of multiple print heads and colored binder, the 3D printing process is generally faster than other additive manufacturing technologies such as fused deposition modeling material jetting which require 100% of build and support material to be deposited at the desired resolution. In 3D printing, the bulk of each printed layer, regardless of complexity, is deposited by the same, rapid spreading process.
As with other powder-bed technologies, support structures are generally not required because loose powder supports overhanging features and stacked or suspended objects. The elimination of printed support structures can reduce build time and material use and simplify both equipment and post-processing. However, de-powdering itself can be a delicate, messy, and time-consuming task. Some machines therefore automate de-powdering and powder recycling to what extent feasible. Since the entire build volume is filled with powder, as with stereolithography, means to evacuate a hollow part must be accommodated in the design.
Like other powder-bed processes, surface finish and accuracy, object density, and—depending on the material and process—part strength may be inferior to technologies such as stereolithography (SLA) or selective laser sintering (SLS). Although "stair-stepping" and asymmetrical dimensional properties are features of 3D printing as most other layered manufacturing processes, 3D printing materials are generally consolidated in such a way that minimizes the difference between vertical and in-plane resolution. The process also lends itself to rasterization of layers at target resolutions, a fast process that can accommodate intersecting solids and other data artifacts.
Powder bed and inkjet 3D printers typically range in price from $50,000 to $2,000,000 . However, there is a hobbyist DIY kit selling from $800 to convert a consumer FDM printer to powder/inkjet printer.
Limitations.
Parts printed using the binder jetting process are inherently porous and have an unfinished surface, as unlike powder bed fusion the powders are not physically melted and are joined by a binding agent. While the usage of a binding agent allows for high melting temperature (e.g. ceramic) and heat-sensitive (e.g. polymer) materials to be powdered and used for additive manufacturing, binder jetting parts require additional post-processing that can require more time than it takes to print the part, such as curing, sintering, and additional finishing .
Binder jetting is particularly prone to the phenomena of powder bed depletion, which occurs when the binder is dropped onto the surface of the powder bed. This issue is particularly prevalent in binder jetting, as unlike traditional additive manufacturing processes (which utilize high heat to melt and fuse powders together), the "jet" of binder that is dropped onto the bed can cause large agglomerates of semi-bonded powder to be ejected from the surface, leaving behind subsurface depletion zones (for 30 μm SS316 powder, a depletion zone depth of 56±12μm was observed). The growth of depletion zones as subsequent layers of powder are deposited printed can have major ramifications on the quality of parts printed with binder jetting. Ejected agglomerates land on other regions of the bed, causing the surface of the bed to become less even, the dimensions of the final part to be warped and inaccurate, and large subsurface pores to form. Residual defects and stress may also be present throughout, which reduce the strength of the already weaker part (due to the inherent porosity of the binder jetted part) .
These factors limit the usage of binder jetting for high-performance applications, such as for aerospace, as binder jetted parts are generally weaker than those printed with powder bed fusion processes. However, binder jetting is perfect for rapid prototyping and production of low-cost metal parts .


Suzuki HEARTECT platform

The HEARTECT platform is an automobile platform that underpins various Suzuki models since 2014.
Construction.
The platform is claimed to utilize "Advanced High Tensile Steel" and "Ultra High Tensile Steel", which are intended to increase occupant safety in case of a collision. Suzuki also claims that the platform offers increased body stiffness, allowing for better ride quality and handling. Additionally, via a reduction in weight of up to , the platform helps achieve an improved power to weight ratio.
The platform is shown to utilize MacPherson strut front suspension.


Aerospace bearing

Aerospace bearings are the bearings installed in aircraft and aerospace systems including commercial, private, military, or space applications.
Materials include M50 tool steel (AMS6491), carbon chrome steel (AMS6444), the corrosion resistant AMS5930, 440C stainless steel, silicon nitride (ceramic) and titanium carbide-coated 440C.
Typically, special attention is given to the material specification, non-destructive testing, and to the traceability of the bearing (a system of documents that enables an engineer to trace a bearing, typically back to its manufacturing batch and material supply).
Design.
When designing aerospace bearings, it is important to take a few things into account, including:
In order to assure bearing performance, it is necessary for the bearing steel to be of high quality. Jet engine bearings are typically manufactured from metals manufactured using a vacuum arc remelt to enable material requirements to be met.
Jet engine shaft bearings and accessory drive shaft bearings typically use single piece or two piece machined retainers. The pressed steel or moulded retainers found on mass-produced bearings are not used.
Temperature and moisture resistant oils, greases and lubricants are normally specified. If the lubricant is not correct the performance of the bearing will be compromised.
Application.
In jet engines bearings can operate at over 200 degrees Celsius (400 °F) and at speeds over 10,000 rpm for the turbine shafts to over 30,000 rpm in the accessory drives. In wing control surface applications temperatures as low as may be encountered.
Monitoring.
Bearings are a vital factor in many products and assemblies and their performance is often monitored continuously. In jet engines the oil supply is monitored to detect the presence of metallic debris that could identify a failure either of the bearings or of other components whose failure may contaminate the bearings.


Process window

The process window is a graph with a range of parameters for a specific manufacturing process that yields a defined result. Typically multiple parameters are plotted in such a graph with a central region where the process behaves well, while the outer borders define regions where the process becomes unstable or returns an unfavourable result. A statistical evaluation of the process performance is further performed by the calculation of the associated Process Window Index.
Applications.
Typical applications are found in photolithography where the response of a photoresist to parameters like temperature, radiation intensity, critical dimension and sidewall angle of the structures, etc. are plotted versus an optical parameter such as the numerical aperture to optimize the design of an exposure tool or to achieve a reproducible result and high yield.


Electronics cooling

Electronics cooling encompasses thermal design, analysis and experimental characterization of electronic systems as a discrete discipline with the product creation process for an electronics product, or an electronics sub-system within a product (e.g. an engine control unit (ECU) for a car). On-line sources of information are available and a number of books have been published on this topic.
Computer cooling is a sub-topic. Heat sinks are devices that are used to extend the surface area of electronic components available for air cooling, helping to lower the components case temperature. Fans are used to increase the air flow.
Thermal design and analysis is performed using hand calculations or spreadsheets, based on design rules or heat transfer correlations. Computer-aided engineering tools such as computational fluid dynamics are also used.
Active electronics cooling.
Besides passive heat conduction, active cooling consuming electricity can be achieved through the thermoelectric coolers.
When electrical voltage is added to an "n"-type ("p"-type) semiconductor material, the electric filed will drive electrons (holes) from one end to the other, which will also carry the electronic kinetic energy and entropy. A temperature gradient will be finally built up to balance the driven force of electrical field. This is called the Peltier effect, and the refrigeration or cooling device made based on this effect is called the Peltier cooler. One Peltier cooler is at least consisted of one "n"-leg and one "p"-leg, which is also called a Peltier junction. Although, Peltier coolers are generally only around 10-15% as efficient as a reversed Carnot cycle, or as 40–60% efficient as a vapor-compression cycle, it may be the only choice for applications in some special scenarios, including electronics on satellites, in submarines, and at an extremely compact space, due to their solid state nature, low maintenance need, compact size and noise-free operation.
Multiple Peltier junctions, taking care of each specific temperature window, can usually be stacked to further enhance the overall performance on electronics cooling. As active heat pumps which consume power, thermoelectric coolers can produce temperatures below ambient, which is impossible with passive heatsinks, radiator-cooled liquid cooling, or heatpipe HSFs. However, while pumping heat, a Peltier module will typically consume more electric power than the heat amount being pumped.


Closed-loop box reuse

Closed Loop Box Reuse, is the process by which boxes or other containers are reused many times. It is a form of reusable packaging.
This is sometimes suited to a large business where containers are used and reused within the location; the custody of containers stays in secure control. Business-to-business commerce also allows controlled return by reverse logistics; a “closed system” and a circular life cycle.
Containers may be constructed of corrugated fiberboard, corrugated plastic, molded plastic, or other materials. Identification of containers by labels, bar codes, various colored latches or RFID chips is common.
Description.
When closed loop supply chains exist or can be created during work in process or progress, boxes are frequently opened and closed to remove and replace contents for inspections, calibration, testing, quality assurance, powder coating or other purposes. Eliminating tape during this process eliminates human injuries from box cutters, blades and knives as well as eliminating damage to box contents.
A means of closing the containers is usually needed such as lids, covers, straps, staples, tape, latches, clips, bands, Hook-and-loop fasteners, etc. When using devices that hold flaps down and out of the way, they can be stacked and stored open or moved about on carts, conveyors, trucks or pallets while remaining open. This saves time and labor while enhancing [{sustainability]} by reusing clips and undamaged boxes. It is important that these temporary means of closure and reopening does not deface or damage the cartons.
At endpoints in these single or multi-site linear or circular closed loops, the temporary closures are removed for reuse and boxes taped for secure shipping to their next or a final destination.
Alternatively, these fiberboard boxes may be collapsed with their closing devices attached and returned to the loop origin in a flattened manner. This reduces time and spares human injuries caused by cutting tape on tops and bottoms. It also lowers costs for freight and allows for speedy reconstruction of cartons in a tapeless, closed loop.
Containers can be reused dozens of times before disposal or recycling. This leverages supply chain cost savings at the same time it embraces supply chain sustainability.
History.
Reuse of. boxes and other containers has been common for many years. For example, the automotive industry has long used reusable racks, totes, and boxes. One type of “closed loop box reuse” was used by Jack D. and James F. Wilson, coinventors of supportive devices developed to keep cardboard box flaps closed or held open without the use of tape. The closed loop term describes a circular life for boxes and cartons made possible by the help of such supportive devices.
Closed-loop box reuse is the process by which packaging materials can be used and reused to minimize waste. Similar and overlapping terms commonly used are closed-loop recycling, returnable packaging, reusable packaging, sustainable supply chains and circular economy. Laws have been passed in Maine and Oregon to make it the responsibility of producers of waste to pay into a fund based on the amount and the ability of the materials used in their packaging to be recycled. These funds will be employed to reimburse municipalities for eligible recycling and waste management costs, make investments in recycling infrastructure, and help citizens understand how to recycle.
A circular economy is a large-scale model that involves the sharing, leasing, reusing, repairing, refurbishing and recycling of existing material in a global environment. Reverse logistics is an alternative to a traditional linear economy (take, make, waste). It seeks to reduce waste, recover resources at the end of a product's life, and channel it back into production, thus, significantly reducing pressure on the environment. Closed-loop box reuse shares similar goals and perspectives but is specific to the circular life cycle of fiberboard boxes in systems where reuse is the focus.
Environmental impact.
The goal of closed-loop fiberboard box reuse is to reduce waste and pollution. The supply chain accounts for more than 90% of the environmental impact experienced by most consumer goods companies, more than 800 million tons of cardboard and paper are disposed of yearly in the USA. Reusing one ton of fiberboard boxes saves 390 kWh of energy, 46 gallons of oil and 700 gallons of water.
Recycling (or reusing) that same ton of corrugated board produces less than 50% of sulfur-dioxide than if made from raw materials and saves more than 9 cubic yards of landfill. In 2018, over 17 million tons of paper and paperboard were landfilled in the U.S. It is the largest component of municipal solid waste.
Closed loop box reuse allows companies to meet their Circular Economy, ISO, Six Sigma, Lean Manufacturing or Zero Waste goals. Closed loop opportunities exist in assembly lines, pick and pack fulfillment centers, kitting operations, warehouse management systems, and moving and storage businesses.


Die shot

A die shot or die photography is a photo or recording of the layout of an integrated circuit, showings its design with any packaging removed. A die shot can be compared with the cross-section of an (almost) two-dimensional computer chip, on which the design and construction of various tracks and components can be clearly seen. Due to the high complexity of modern computer chips, die-shots are often displayed colourfully, with various parts coloured using special lighting or even manually.
Methods.
A die shot is a picture of a computer chip without its housing. There are two ways to capture such a chip "naked" on a photo; by either taking the photo before a chip is packaged or by removing its package.
Avoiding the package.
Taking a photo before the chip ends up in a housing is typically preserved to the chip manufacturer, because the chip is packed fairly quickly in the production process to protect the sensitive very small parts against external influences. However, manufacturers may be reluctant to share die shots to prevent competitors from easily gaining insight into the technological progress and complexity of a chip.
Removing the package.
Removing the housing from a chip is typically a chemical process - a chip is so small and the parts are so microscopic that opening a housing (also named delidding) with tools such as saws, sanders or dremels could damage the chip in such a way that a die shot is no longer or less useful. For example, sulphuric acid can be used to dissolve the plastic housing of a chip. This is not a harmless process - sulphuric acid can cause a lot of health damage to people, animals and the environment. Chips are immersed in a glass jar with sulphuric acid, after which the sulphuric acid is boiled for up to 45 minutes at a temperature of 337 degrees Celsius. Once the plastic housing has decayed, there may be other processes to remove leftover carbon, such as with a hot bath of concentrated nitric acid. After this, the contents of a chip are relatively exposed and a picture can be made of the chip with macrophotography or microphotography.


Onto Innovation

Onto Innovation Inc. is an American semiconductor company formed in 2019 from the merger of Rudolph Technologies, Inc. and Nanometrics Incorporated. Onto Innovation is traded as on the New York Stock Exchange, it is a provider of process and process control equipment and software for microelectronic manufacturing industries (primarily semiconductor). The company's product offering includes automated defect inspection and metrology systems, probe card test and analysis systems, and lithography step-and-repeat systems. In addition, Onto Innovation provides a broad range of software products designed to improve yield, control processes and reduce manufacturing costs.
History.
Rudolph Research: 1940–1995.
Rudolph Technologies, Inc. (RTI) traces its origins to 1940, when Otto Curt Rudolph formed O.C. Rudolph & Sons, Inc. Originally an importer of microscopes and scientific instruments, this RTI predecessor was renamed in October 1970 to Rudolph Research Corporation. The company designed optical equipment for laboratories and universities.
The company Otto Rudolph established continued to evolve, making breakthroughs in ellipsometry including the first production-oriented ellipsometer for thin, transparent film measurements. The company continued development of its metrology products, securing new patents along the way.
Nanometrics: 1975–2019.
Nanometrics was founded in 1975 and was a pioneer and innovator in the field of optical metrology. In 1984, the company started publicly trading.
Formation of Rudolph Technologies: 1996–1999.
In June 1996, Richard Spanier, Ph.D., chief executive officer of Rudolph Research, forged a partnership agreement with Boston-based Riverside Partners and New York-based Liberty Partners who, along with others, invested in the company. At that time, Dr. Spanier retired his active role in the company and semiconductor industry veteran Paul F. McLaughlin was named as CEO. In August 1999, the name of the company was changed to Rudolph Technologies, Inc.
In November 1999, RTI made its initial public offering of common stock. Revenues grew dramatically, reaching a record $38.1 million. A new facility opened early in the year, and the company launched a new product, the MetaPULSE® line of copper film measurement tools.
Rudolph Technologies: 2000–2019.
In July 2002, RTI agreed to acquire the Richardson, Texas-based defect control company ISOA, Inc. A spin-off from Texas Tech University's International Center for Informatics Research, ISOA had been licensing technology to the semiconductor industry for about 16 years, offering defect detection software. The deal was completed in September, with ISOA becoming RTI's Yield Metrology Group.
Several months later, RTI expanded into China by establishing an office in Shanghai's Pudong industrial area. In subsequent years, the company established additional offices in all semiconductor manufacturing regions of the world including Japan, Europe, South Korea, Taiwan and Singapore.
In 2006, a merger was completed with Minnesota-based August Technology Corporation, growing Rudolph's workforce to 550 employees. This acquisition brought Rudolph into the ‘back-end’ of the manufacturing process.
In 2007, the company acquired the semiconductor business of Washington-based Applied Precision LLC, adding probe card test and analysis to the company's portfolio. The acquisition of RVSI Inspection LLC and its Wafer Scanner inspection system was announced in 2008. Adventa Control Technologies, Inc., a provider of process control software, was acquired in 2009, and an acquisition of MKS Instruments, Inc.’s Yield Dynamics business was completed in 2010. Rudolph announced two acquisitions in 2012. NanoPhotonics GmbH, Mainz, Germany (unpatterned wafer inspection); and Azores Corp., Wilmington, MA (Rudolph's entry into the advanced packaging and FPD lithography markets). In 2013 Rudolph announced the acquisition of selected assets of Tamar Technology, Newbury Park, CA, a supplier of 3D metrology technologies. Rudolph acquired the inspection technology of Stella Alliance in 2015, adding patents to enhance its inspection capability.
In November 2015, Rudolph announced the retirement of Paul F. McLaughlin and appointment of Michael P. Plisinski as CEO and Director.
As of January 19, 2017, Rudolph Technologies Inc. had a market capitalization of about $713 million.
In January 2017, Voce Capital Management LLC in a letter to investors, urged merging semiconductor-equipment makers Rudolph Technologies Inc. and Nanometrics Inc. The merger eventually occurred and closed on October 30, 2019. According to the Joint Proxy Statement announcing the terms of the merger, talks began in the first quarter of 2016 and continuing into 2017, Nanometrics and Rudolph engaged in discussions concerning a potential business combination between the two companies, to be structured as a merger of equals transaction, which discussions between the parties are referred to as the 2017 discussions. In connection with the 2017 discussions, in February 2016, Nanometrics and Rudolph entered into a mutual confidentiality agreement, which was subsequently extended in January 2017.
On October 25, 2019, Rudolph merged with Nanometrics Incorporated to become Onto Innovation, trading as .
The company is now headquartered in Wilmington, Massachusetts, with additional U.S. operations in New Jersey, Minnesota, California, Texas, Oregon and Washington. Manufacturing operations for inspection and some metrology products are consolidated in Minnesota; most metrology manufacturing operations is in California; stepper manufacturing is located in Wilmington, Massachusetts.
Products and services.
Semiconductor fabrication, packaging and testing.
Semiconductor device fabrication is the process used to create the integrated circuits that are found in commonly used electronic devices and electrical equipment. It is a multiple-step process during which electronic circuits are gradually built by adding elements and layers of material on a substrate made of pure silicon, or various compounds in the case of specialized applications, hundreds of steps performed by specialized process tools are required before the wafer moves to a final packaging facility.
The focus of packaging and assembly is to ensure an electrical connection from the die to the circuit board, to encapsulate the package for mechanical integrity and to withstand thermal variations. The era of slim form-factor devices, such as smart phones, implies high level of functionality in very dense footprint. Due to these requirements, the challenges in packaging, assembly and test have significantly increased and advanced packaging techniques such as bumping or through-silicon via are necessary.


Officine Meccaniche (disambiguation)

Officine Meccaniche is an Italian car and truck manufacturing company.
Officine Meccaniche may also refer to:


Friction stir spot welding

Friction stir spot welding is a pressure welding process that operates below the melting point of the workpieces. It is a variant of friction stir welding.
Process description.
In friction stir spot welding, individual spot welds are created by pressing a rotating tool with high force onto the top surface of two sheets that overlap each other in the lap joint. The frictional heat and the high pressure plastify the workpiece material, so that the tip of the pin plunges into the joint area between the two sheets and stirs-up the oxides. The pin of the tool is plunged into the sheets until the shoulder is in contact with the surface of the top sheet. The shoulder applies a high forging pressure, which bonds the components metallurgically without melting. After a short dwell time, the tool is pulled out of the workpieces again so that a spot weld can be made about every 5 seconds.
The tool consists of a rotating pin and a shoulder. The pin is the part of the tool that penetrates into the materials. Both the pin and the shoulder may be profiled to push the plasticized material in a particular direction and to efficiently break-up and disperse the oxide skins on the adjacent surfaces. After retracting the tool, a hole remains, when using one-piece tools, which have already proven themselves as very reliable in the automotive and the rail vehicle industry. Often the rotating tool is surrounded by a non-rotating clamping ring with which the workpieces are pressed firmly against each other before and during welding by applying a clamping force. The clamping ring can also be used to reduce the pressing out of plasticized material to avoid the formation of burrs or beads to apply inert gas or to cool the tool via compressed air.
The most important process parameters are the speed and contact pressure. This results in the plunge feed rate for a given workpiece material. Modern spot welding guns can be used either via position control or force control or via a product-specific programmed force-displacement control. Often, position control is used until a certain displacement is reached, and then the control system is switched to force control during the dwell time. Even during the force-controlled dwell time, certain position values can be specified, which should not be undermatched or exceeded.
Spot welding guns.
Friction stir spot welding is performed with a spot welding gun, which is mounted on a console, flanged to an articulated robot or manually operated with a balancer to the component.
Process advantages.
Friction spot welding is characterized by a number of process advantages. Any damage to the material caused by the extreme heat, such as that produced by laser or arc welding, will not occur. In particular, in the case of artificially aged aluminum alloys, the strength in the weld seam and the heat-affected zone is much higher than in conventional welding methods.
Industrial use.
Friction stir spot welds have a high strength, so they are even suitable for parts that are exposed to particularly high loads. In addition to automotive and rail vehicle construction, the aerospace industry is developing the process e.g. for welding cockpit doors for helicopters. In the electrical industry aluminum and copper can be friction stir spot welded. Other applications are in façade and furniture manufacture, where the low heat input, especially in anodized sheets, leads to excellent optical properties.


Rane (Madras)

Rane (Madras) Ltd is a part of the Rane group of companies involved in the manufacture and distribution of steering and suspension systems. The main components manufactured by the company include Manual Steering Gear Products (SGP) and Suspension & Steering Linkage Products (SSLP). The other products include tie rod assemblies, drag link assemblies, center link assemblies and gear shift ball joints. Automobile companies that use its products include Ashok Leyland, Volvo, M&M, Tafe, Tata among many others. Tata motors remains its major customer and is the primary parts manufacturer for Tata's Nano. The company has also set up a dedicated plant for Tata Nano in Sanand, Gujarat. The company was forced to change its manufacturing facility from West Bengal to Gujarat after Tata moved out.
History.
Rane group of companies was founded by Shri T. R. Ganapathy Iyer in the year 1929 and the group was originally named as Rane (Madras) Ltd. It started off as a distributor of automobiles and parts. After his death, the business was taken over by his son-in-law Lakshmana Iyer Lakshminarayan, popularly known as LLN, among friends and business circles. Under the leadership of LLN, the company was shaped into an auto-component business house. LLN remained as the founder chairman of the group for over three decades.
During the early periods. Rane Madras Ltd was engaged in trading only. Later in the year 1960, they completely dropped trading and started manufacturing and it all started with the manufacture of Tie Rod ends at their plant in Velachery, Chennai. Later; as the automobile industry flourished, the business spread to the manufacturing of other suspension and steering systems. As a major turn of events, in 2005 the company was de-merged from the group and the group holding company called Rane Holding Ltd (RHL) and several other subsidiary companies were formed. It was during this period that Rane (Madras) Ltd emerged as a public limited company. Later, Rane Holding Ltd made additional investment in the company, and thus Rane (Madras) Ltd became a wholly owned subsidiary of the Rane Holdings Ltd. It remained a major manufacturer and supplier of major OEMs in India and abroad.
Over the years Rane (Madras) Ltd has grown to be the largest in the group, both in terms of size and turnover, with five manufacturing plants in Chennai and Kancheepuram in Tamil Nadu, Mysore in Karnataka, Thirubuvanai in Pondicherry and Pantnagar in Uttarakhand. Each of the company's production plants addresses a specific industry segment. The production facilities in Mysore cater to the tractor and commercial vehicle segment; the Pondicherry plant to the passenger car segment; the plant in Chennai caters to the light commercial vehicle, heavy commercial vehicle and utility vehicle segment; the Kancheepuram plant to the export market and the manufacturing facility in Pantnagar (Uttarakhand) supplies gears exclusively to Tata Motors Ltd. The company has also started setting up its plant in Gujarat
In 2013 this group merged with GTC inc. (Gaurav Jagannath Rane) Director & S.E.O.


The Italian Union of Chemical, Energy and Manufacturing Workers (, UILCEM) was a trade union representing manufacturing and utility workers in Italy.
The union was founded on 25 March 1999, when the Italian Union of Chemical, Energy and Resource Workers merged with the Italian Union of Public Service Workers. Like both its predecessors, it affiliated to the Italian Union of Labour. In 2013, it merged with the Italian Union of Textile and Clothing Workers, to form the Italian Union of Textile, Energy and Chemical Workers.


Wire wrap

Wire wrap is an electronic component assembly technique that was invented to wire telephone crossbar switches, and later adapted to construct electronic circuit boards. Electronic components mounted on an insulating board are interconnected by lengths of insulated wire run between their terminals, with the connections made by wrapping several turns of uninsulated sections of the wire around a component lead or a socket pin.
Wires can be wrapped by hand or by machine, and can be hand-modified afterwards. It was popular for large-scale manufacturing in the 1960s and early 1970s, and continues today to be used for short runs and prototypes. The method eliminates the design and fabrication of a printed circuit board. Wire wrapping is unusual among other prototyping technologies since it allows for complex assemblies to be produced by automated equipment, but then easily repaired or modified by hand.
Wire wrap construction can produce assemblies that are more reliable than printed circuits: connections are less prone to fail due to vibration or physical stresses on the base board, and the lack of solder eliminates soldering faults such as corrosion, cold joints and dry joints. The connections themselves are firmer and have lower electrical resistance due to cold welding of the wire to the terminal post at the corners.
Wire wrap was used for assembly of high frequency prototypes and small production runs, including gigahertz microwave circuits and supercomputers. It is unique among automated prototyping techniques in that wire lengths can be exactly controlled, and twisted pairs or magnetically shielded twisted quads can be routed together.
Wire wrap construction became popular around 1960 in circuit board manufacturing, and use has now sharply declined. Surface-mount technology has made the technique much less useful than in previous decades. Solder-less breadboards and the decreasing cost of professionally made PCBs have nearly eliminated this technology.
History.
Manually wrapped wires were common in early 20th century point-to-point electronic construction methods in which a strong connection was needed to hold the components in place. Wires were wrapped by hand around binding posts or spade lugs and then soldered.
Modern wire wrapping technology was developed after WWII at Bell Laboratories as a means of making electrical connections in a new relay being designed for use in the Bell Telephone system. A design team headed by Arthur C. Keller developed the “Keller Wrap Gun”, and the entire wrap system was passed over to Western Electric for industrial application. After a “make or buy” committee at Western Electric decided to have the hand tool manufactured by an outside vendor, Western Electric sent the tool contract out for bids. Keller Tool of Grand Haven, Michigan, a supplier of rotary hand tools to Western Electric, won the contract and made several design changes to make the tool easier to manufacture and to use. Keller began manufacturing the tools in 1953, and subsequently obtained a license from Western Electric allowing sale of the technology on the open market. The tool was marketed under its original name – since the name of the manufacturer was coincidentally the same as the name of the inventor.
IBM's first transistorized computers, introduced within the late 1950s, were built with the IBM Standard Modular System that used wire-wrapped backplanes.
Method.
A correctly made wire-wrap connection for 30 or 28 AWG wire is seven turns (fewer for larger wire) of bare wire with half to one and a half turns of insulated wire at the bottom for strain relief. The square hard-gold-plated post thus forms 28 redundant contacts. The silver-plated wire coating cold-welds to the gold. If corrosion occurs, it occurs on the outside of the wire, not on the gas-tight contact where oxygen cannot penetrate to form oxides. A correctly designed wire-wrap tool applies up to twenty tons of force per square inch on each joint.
The electronic parts sometimes plug into sockets. The sockets are attached with cyanoacrylate (or silicone adhesive) to thin plates of glass-fiber-reinforced epoxy (fiberglass).
The sockets have square posts. The usual posts are square, high, and spaced at intervals. Premium posts are hard-drawn beryllium copper alloy plated with a of gold to prevent corrosion. Less-expensive posts are bronze with tin plating.
30 gauge (~0.0509mm2) silver-plated soft copper wire is insulated with a fluorocarbon that does not emit dangerous gases when heated. The most common insulation is "Kynar". The 30 AWG Kynar wire is cut into standard lengths, then one inch of insulation is removed on each end.
There are three ways of placing wires on a board. In professionally built wire-wrap boards, long wires are placed first so that shorter wires mechanically secure the long wires. Also, to make an assembly more repairable, wires are applied in layers. The ends of each wire are always at the same height on the post, so that at most three wires need to be replaced to replace a wire. Also, to make the layers easier to see, they are made with different colors of insulation. In space-rated or airworthy wire-wrap assemblies, the wires are boxed, and may be conformally coated with wax to reduce vibration. Epoxy is never used for the coating because it makes an assembly unrepairable.
Tooling.
A "wire wrap tool" has two holes. The wire and of insulated wire are placed in a hole near the edge of the tool. The hole in the center of the tool is placed over the post.
The tool is rapidly twisted. The result is that 1.5 to 2 turns of insulated wire are wrapped around the post, and above that, 7 to 9 turns of bare wire are wrapped around the post. The post has room for three such connections, although usually only one or two are needed. This facilitates manual wire-wrapping to be employed for modifications or repairs.
The turn and a half of insulated wire helps prevent wire fatigue where it meets the post.
Above the turn of insulated wire, the bare wire wraps around the post. The corners of the post bite in with pressures of tons per square inch. This forces all the gases out of the area between the wire's silver plate and the post's gold or tin corners. Further, with 28 such connections (seven turns on a four-cornered post), a very reliable connection exists between the wire and the post. Furthermore, the corners of the posts are quite "sharp": they have a quite-small radius of curvature.
Automation.
Automated wire-wrap machines, as manufactured by the Gardner Denver Company in the 1960s and 1970s, were capable of automatically routing, cutting, stripping and wrapping wires onto an electronic "backplane" or "circuit board". The machines were driven by wiring instructions encoded onto punched cards, Mylar punched hole tape, and early micro computers.
The earliest machines (14FB and 14FG models, for example) were initially configured as "horizontal", which meant that the wire wrap board was placed upside down (pins up) onto a horizontal tooling plate, which was then rolled into the machine and locked onto a rotating (TRP table rotational position of four positions) and shifting (PLP = pallet longitudinal position of 11 positions) pallet assembly. These machines included very large hydraulic units for powering the servos that drove the ball screw mounted "A" and "B" drive carriages, a tall electronics cabinet loaded with hundreds of IBM control relays, many dozens of solenoids for controlling the various pneumatic mechanical subsystems, and an IBM 029 card reader for positioning instructions. The automatic wire wrap machines themselves were quite large, tall and square. Servicing the machines was extremely complex, and often meant climbing inside them just to work on them. This could be quite dangerous if safety interlocks were not maintained properly.
Later, somewhat smaller machines were "vertical" (14FV) which meant the boards were placed onto a tooling plate with pins facing the machine operator. Gone were the hydraulic units, in favor of direct drive motors to rotate the ball screws, with rotary encoders to provide positioning feedback. This generally provided better visibility of the product for the operator, although maximum wrap area was significantly less than the horizontal machines. Top speeds on horizontal machines were generally around 500-600 wires per hour, while the vertical machines could reach rates as high as 1200 per hour, depending on board quality and wiring configurations.
Considerations.
Wire-wrap works well with digital circuits with few discrete components, but is less convenient for analog systems with many discrete resistors, capacitors or other components (such elements can be soldered to a header and plugged into a wire wrap socket). The sockets are an additional cost compared to directly inserting integrated circuits into a printed circuit board, and add size and mass to a system. Multiple strands of wire may introduce cross-talk between circuits, of little consequence for digital circuits but a limitation for analog systems. The interconnected wires can radiate electromagnetic interference and have less predictable impedance than a printed circuit board. Wire-wrap construction cannot provide the ground planes and power distribution planes possible with multilayer printed circuit boards, increasing the possibility of noise.