Hot plate welding

Hot plate welding, also called heated tool welding, is a thermal welding technique for joining thermoplastics. A heated tool is placed against or near the two surfaces to be joined in order to melt them. Then, the heat source is removed, and the surfaces are brought together under pressure. Hot plate welding has relatively long cycle times, ranging from 10 seconds to minutes, compared to vibration or ultrasonic welding. However, its simplicity and ability to produce strong joints in almost all thermoplastics make it widely used in mass production and for large structures, like large-diameter plastic pipes. Different inspection techniques are implemented in order to identify various discontinuities or cracks.
History.
Hot plate welding was first used in the early 1930s for joining PVC.
It gained in popularity with the prevalence of polyolefins, which are difficult to adhesively bond.
By the 1960s, it was among the most widely used plastic welding methods.
Hot plate welding was used for pipelines and appliances as well as injection moldings. Numerous national and international associations for welding have specifications and guidelines for hot plate welding, including the Deutscher Verband fuer Schweissen (DVS) in Germany, the American Welding Society (AWS) in the United States, and the Comité Européen de Normalisation (CEN) in Europe.
Process.
Conventional hot plate welding.
The hot plate welding process can be divided into four phases: matching, heating, change-over, and welding/forging.
The matching phase serves to match the geometry of the weld surfaces to the theoretical welding plane. The weld surfaces are heated through conduction by physical contact with the hot plate. The hot plate temperature range is above the melting temperature of the material, and a constant pressure between 0.2 and 0.5 MPa is applied against the hot plate. This causes the weld surfaces to conform to the hot plate, which has the desired weld geometry. This also removes surface irregularities that would increase thermal contact resistance. After the parts are in full contact with the hot plate, the heating phase starts and pressure is reduced to a minimum.
During the heating phase, the weld region is heated conductively until melted, without substantial displacement of the material. Pressure is maintained either at a minimum to keep the parts and the hot plate in contact or at zero with a preset displacement. The melt surface reaches approximately below the temperature of the hot plate. The viscosity of the melted material can be controlled through the temperature of the hot plate and the heating time. The surface of hot plate is often coated with PTFE to stop the molten plastic from sticking, which limits the hot plate temperature to .
The temperature of the parts during this phase can be modeled by assuming a constant temperature boundary condition and using the one-dimensional heat equation:
where "θ" is the temperature, "x" is the position, "t" is the time, "θi" is the initial temperature, "θs" is the constant surface temperature, "κ" is the thermal diffusivity, and erfc is the complementary error function. This model is valid for most cases, since the thermal contact resistance is low and the thermal mass of the hot tool is large compared to the plastic parts. For more precise predictions of the heat flow, the thermal contact resistance and the temperature dependence of the thermal properties of the plastic also need to be considered.
After sufficient heating time, the change-over phase begins. During this phase, the parts are retracted from the hot plate, the plate is quickly moved away, and the parts are brought together. The change-over should be as short as possible, because the melted region cools off during this time.
The welding/forging phase begins when the two molten surfaces are pressed together. This creates intermolecular diffusion of the plastic molecules according to reptation theory. Weld strength is provided by entanglement of the diffused plastic molecules. The necessary welding pressure depends on the melt viscosity and wall thickness of the parts and usually ranges between 0.025 and 0.05 MPa. This pressure is maintained while the melted material cools and resolidifies. During this, some plasticized material in the weld zone is squeezed out, forming flash. Mechanical stops may be used to limit the amount of squeezed out material in order to prevent a cold weld.
Variants.
Common variants of conventional hot plate welding include high-temperature and non-contact versions. Both of these variants help with the problem of material sticking to the hot plate between weld cycles; the stuck material can degrade and transfer to subsequent welds, resulting in poor quality and aesthetically unappealing welds.
With high-temperature hot plate welding, an uncoated hot plate is heated to between , as the PTFE coating degrades at high temperatures. The high temperature decreases the viscosity of the melt, so it can peel off from the hot plate when removing the parts. This can be accompanied during the change-over phase by rapid movement of the parts from the hot plate; this prevents stringing of the melted plastic due to its viscoelastic properties. Any residual material on the hot plate's surface is usually either oxidized away or mechanically removed. With some thermoplastics, the residual material cannot be easily removed and accumulates over time. The hot plates may need to be removed and cleaned between cycles. With the higher temperatures, the matching and heating phases are shortened from those of conventional hot plate welding. However, reduced weld strength from thermal degradation of the plastic can still occur, though most of the degraded material is forced out by the flow of melted material. High-temperature hot plate welding is known to perform well for:
With non-contact hot plate welding, the weld surfaces are melted without physical contact with the hot plate through convection and radiation heating. The hot plate temperature is between , and the weld surfaces are placed about from the hot plate. Heat input needs to be controlled to prevent thermal degradation while plasticizing the material. This variant has no matching phase, so part fit must be good prior to welding, with part deviation not exceeding . In practice, non-contact hot plate welding is only used for small parts whose dimensions do not exceed . An additional consideration is the stack effect when the hot plate is oriented vertically, which can cause uneven heating of the weld surfaces.
Another variant is hot wedge or hot shoe welding for joining thin sheets with lap seams. A heated wedge travels between the two sheets and melts the weld surfaces while wedge rollers apply light pressure to force intimate contact; drive rollers apply pressure at the tip of the wedge where the sheets converge to form a continuous seam.
Hot wedge welding can produce either single or dual seam joints. For dual seam joints, a split wedge that is unheated in the middle is used. This leaves an unwelded air pocket between the seams that can be pressurized to nondestructively test the joint integrity. With hot wedge welding, the speed of travel is an added parameter as the wedge unit is self-propelled by the rollers. The typical temperature range when welding high-density polyethylene (HDPE) is ; the travel speed is typically .
Parameters.
Parameters used in hot plate welding are the hot plate temperature, the pressure (or displacement) during matching, the pressure during heating, the pressure and displacement during the weld phase, and the times for matching, heating, change-over and cooling. These parameters have an interdependent effect on the weld quality and cannot be set individually.
The hot plate temperature is taken at the surface of the plate. It is set based on the hot plate welding variant along with the properties of the material, including melting temperature, melt viscosity, and thermal degradation limits. Conventional hot plate welding uses temperatures above the melting temperature. The high-temperature variant uses temperatures above the material's degradation temperature, about above the melting point. The non-contact variant uses temperatures above the melting point. With non-contact welding, the radiation heating depends not only on the temperature but also on the emissivity of the hot plate material.
The pressure during the matching phase removes warpage of the weld surfaces to ensure full contact with the hot plate without causing the parts to deform. During the heating phase, a minimum pressure is maintained to keep the parts in contact with the hot plate, as a larger pressure would squeeze out material. The welding pressure brings the molten weld surfaces into intimate contact and squeezes out entrapped air. Too high a pressure would squeeze out most of the hot material from the joint, leaving cooler material to form a cold weld. Too low a pressure limits intermolecular diffusion and produces a weak weld. A mechanical stop may be used in the welding phase to limit the amount of material squeeze out by varying the welding pressure.
The matching and heating times control the amount of heat input during those phases. The matching time is set so that surface irregularities are melted and removed. The heating time determines the melt layer thickness. Too thick a melt results in excess flash and unfavorable molecular orientation at the joint interface. Too thin a melt produces a brittle weld. The change-over time determines the temperature of the melted material as welding begins and, therefore, should be as short as possible to minimize surface cooling. Typical change-over times are around 2 to 3 seconds, even for large parts. Cooling time refers to the time until the joined parts have solidified (when the molten material has cooled below its melting temperature) and can be removed from the machine. The welded part should not be stressed until it has further cooled until room temperature.
Equipment.
Hot plate welding equipment consists of two main components, a clamping fixture and one or multiple hot plates. The primary function of the fixture is to provide support during the welding process to prevent deformation under welding pressure. Conventional machines have fixtures that fully conform to the parts being welded and allow for flexibility in production by accepting different fixture configurations. Custom machines may be configured to weld a specific component and do not provide as much flexibility as standard machines.
Hot plates are generally designed for specific working temperatures. Hot plates for conventional hot plate welding have a working temperature of at least and are made from aluminum alloys. The hot plates may also be coated in Polytetrafluoroethylene (PTFE) to prevent sticking of the polymer to the hot plate. Caution should be taken as the PTFE coatings degrade over time and sets of interchangeable fixtures should be available during continuous operation. Hot plates for high-temperature hot plate welding have a maximum working temperature of and are made from aluminum bronze alloys. Due to the lower thermal conductivity of these alloys precaution must be taken to ensure that there is uniform heating along the hot plate surface. PTFE has a maximum working temperature of therefore, non-stick coatings cannot be used for this type of operation. Lastly, hot plates for non-contact hot plate welding are used for temperatures up to are made from either aluminum bronze or stainless steels.
Hot plate welding machines are generally operated by pneumatic, hydraulic or electromechanical controls. Machines can be configured to perform welds with the faying surface in either the horizontal or vertical position. Longer components such as pipes are more commonly welded in the horizontal position whereas moldings with internal fittings such as a starter battery are welded in the vertical position. A proportional-integral-derivative (PID)  controller also assists in maintaining desired temperatures during each process.
Joint Types.
While there are various joint configurations, a butt joint in which the two joining materials are aligned along the same plane is one of the most common joint designs for thermoplastics. There are various modifications of this joint that are implemented for different applications which include the following listed below.
Material weldability.
Hot plate welding can be used for joining all thermoplastics and thermoplastic elastomers whose melting temperature range lies below their decomposition temperature. Since only the plastic itself can be joined, additives, used to improve material properties or reduce cost, can reduce weldability. Additives can also reduce weld strength by acting as stress concentrators. Examples of additives include stabilizers, lubricants, processing aids, coloring agents, reinforcing materials (talcum, glass fibers, carbon fibers, etc.).
The water content of the plastic also affects weldability. This affects thermoplastics that absorb water from the surrounding air, mainly amorphous thermoplastics. High water content can lead to the formation of bubbles during heating and joining, reducing weld strength. Therefore, parts should be welded shortly after injection molding, stored in a dry environment, or welded with adjusted parameters.
Hot plate welding can be used to join some combinations of dissimilar thermoplastics. Typically, semi-crystalline plastics are only compatible with semi-crystalline plastics, and amorphous plastics are only compatible with amorphous plastics. If the plastics have the same melting point and melt viscosity, conventional or high-temperature hot plate welding can be used. With different melting points or different viscosities, dual hot plates should be used, with each hot plate set to a different temperature. Common thermoplastic combinations include:
Applications.
Hot plate welding is used for joining parts ranging from a few centimeters up to 1.6 meters. It is also used for making continuous welds in lining membranes. Its usage can be divided into two main categories, namely production applications and pipe welding. These differ in their equipment and joint designs.
Production applications.
One major industry using hot plate welding is the automotive sector. Tail light housings made of ABS are joined with lenses made of either PMMA or PC using a modified butt joint. ABS and PMMA have similar melting temperatures and can be welded using a single hot plate, while ABS and PC requires dual hot plates due to PC's higher melting temperature. Vacuum suction cups are used to move the parts to prevent scuffing. Both conventional and high-temperature variants are used. A typical cycle time is 60 seconds with a hot plate temperature of 370 °C.
Fuel tanks made of blow-molded HDPE need as many as 34 parts welded to it, including clips, filler necks, vent lines, Heat shield boss plug, Gas vent value/Roll over Valves, Breather Nipple and brackets. The parts are welded individually using groove butt joints. Each component needs a different matching time, and cycle times are less than a minute per component.
The cases and lids of automotive batteries are made of thin PP copolymers, which have low melt viscosity. High-temperature hot plate welding is used on butt joints with flash covers. A typical machine can weld two batteries in a time of less than 30 seconds.
Other automotive components welded by hot plate are carburetor floats, coolant and washer fluid reservoirs, and ventilation ducts. Non-automotive items include dishwasher spray arms, laundry detergent boxes, steam iron reservoirs, HDPE barrels, PP transport pallets, medical needle disposal boxes, and PVC window frames.
Pipe welding.
Hot plate welding, referred to as fusion welding in many industries, is commonly used to join plastic pipes. These pipes, as opposed to steel ones, are less likely to rupture during an earthquake. Pipe welding uses special joint configurations, namely butt, socket and saddle/sidewall, each with its own welding procedures.
Butt fusion welding has similar process phases as conventional hot plate welding. Before welding, the pipe ends are faced and the profiles are rounded and aligned with each other. The remaining phases proceed as normal, though sometimes the matching phase can be skipped. When welding dissimilar plastics, in lieu of dual hot plates, the pipe with the lower melt flow index can be heated earlier than the other, such that both pipe ends have the same melt viscosity at the end of the heating phase. After cooling, the flash bead is sometimes removed to leave smooth surfaces on the interior and exterior. Problems with the weld can be determined by inspecting this bead.
Socket fusion welding uses male and female heating tools attached to a hot plate to heat the exterior of the pipe and the interior of the socket simultaneously. This is typically used for pipes ranging from 40 to 125 millimeters. With this joint, the welding pressure is supplied by the interference fit of the pipe and socket, so these parts as well as the heating tools need to be within tolerance.
Saddle/sidewall fusion welding is used for joining saddle fittings onto the sidewall of a pipe to create branches. The exterior of the pipe and the matching surface of the saddle fitting are heated using concave and convex heating tools. The saddle fusion machine applies welding force through the centerline of the pipe. Prior to welding, the exterior of the pipe needs to be cleaned of all contaminants, because the melt layer of the pipe is not displaced from the joint.
Non-destructive Testing (NDT).
There are two methods of testing including non-destructive and destructive testing. While the quality of a weld can only be determined through destructive means, NDT allows for the determination of defects in the welded region. The following section will highlight some of the non-destructive methods used in welding of thermoplastics.
Visual inspection.
Visual inspection testing can only be used to detect flaws on the surface of the weld but is the least expensive method of NDT. This method of inspection may be performed both during and post welding. During welding the operator is inspecting for discoloration, misalignment, notches and other surface discontinuities. Post welding inspection allows the operator to inspect for microstructural features which may be detrimental to the welded part.
X-ray testing.
X-ray testing is a costly method of inspection; therefore, it is generally limited to pressure vessels and pipelines carrying hazardous materials. This method is most effective when the densities of the imperfection and the plastic have a substantial difference and is used for detection of voids, inclusions and other imperfections. A disadvantage to this method is that microstructural defects cannot be determined through this method of testing.
Leak-tightness test.
This method of testing is most often used for welded pipes and other closed containers. There are different variations of this test which are dependent on the type of medium (water, air, gas) used to pressurize the sample. It is common to conduct this test in vacuum conditions.
High-voltage test.
High voltage testing known as “spark test” is an alternative to the leak-tightness test. This test in performed by coating the weld with an electrically conductive substance such as a wire, fibers or coils. When a voltage is applied an arc will form, showing the presence of a leak. This test is not well suited for polar thermoplastics such as PVC as they will generate heat leading to potential degradation of the weld.
Ultrasonic testing.
Ultrasonic testing uses high frequency waves that travel through the welded regions. These waves are able to detect defects based on the different densities between the imperfection and plastic part. There are two primary methods of conducting ultrasonic testing and that is by using a transmitter and receiver in conjunction or by using an ultrasonic transducer. These conventional methods similar to X-ray testing are not able to detect microstructural changes in the weld. Advanced ultrasonic testing such as phased array ultrasonics (PAUT) is currently being developed for inspection of hot plate and electrofusion joints.
Polyethylene (PE) pipes are desirable over other materials such as metals for the transportation of fluids due to their resistance to corrosion leading longer lifespans. They are however, limited from being used in nuclear power plants due unreliable NDT methods. Current methods involve using practices that do not provide a complete analysis of a welded PE pipe.
Using a butt joint configuration produces a small fusion zone and inspection is further complicated due to the high attenuation of PE. Proper probe placement is also limited during inspection due to interference with the weld bead. The PAUT system has five primary components. These components are the phased array probe, probe wedge, probe holder, scanner and flaw detector. A minimum of four phased array probes are required for the ultrasonic signal to detect a flaw. The membrane water wedge transmits the ultrasound from the probes into the pipe while minimizing energy loss and the probe holder ensures proper contact between the wedge and pipe. The scanning system made specifically for this testing method carries the probe around the joint of the pipe during inspection. Lastly, the flaw detector analyzes the signal from the probe. This method is specifically designed for  inspection of electrofusion and butt fusion welds of various sized pipes ranging from a thickness of 8-65mm and a diameter of 90-800mm. PAUT is well suited for the detection of:
Two ISO reports are under development and being reviewed by technical committee (TC) 138 (Plastic pipes, fittings and valves for the transport of fluids) to include PAUT as a method of volumetric NDT of PE pipes. A procedure has also been made for UT of butt fusion joints including but not limited to HDPE and medium-density polyethylene (MDPE). The ISO and ASME standards are listed as:


Final assembly schedule

Final Assembly Schedule, often abbreviated as FAS and sometimes referred to as finishing schedule, is a schedule of end items to finish the product for specific customer orders in a make to order (MTO) or assemble-to-order (ATO) environment.
Overview.
Finishing schedule may involve assembly but also final mixing, cutting, packaging etc. The FAS is prepared after receipt of customer order. FAS schedules the operations required to complete the product from the level where it is stocked (or master-scheduled) to the end-item level.
Final assembly schedule (FAS) entries are needed when end products do not appear in the MPS. These end items are assembled to order or have several customer options that can be combined in various configurations. These products belong to the category of products with variants and options wherein many shippable end-item products are assembled from few standard components (in modular construction and modular design). For these products, two different schedules are required: master production schedule (MPS) for end-item components and final assembly schedules (FAS) for shippable products.
Assembly-to-order.
FAS controls the portion of the business from fabricated components and sub-assemblies planned on the basis of forecast to customer-ordered shippable products in ATO environments.
Make-to-order.
In MTO business, it states the specific schedule for satisfying customer orders.
Make-to-stock.
In make-to-stock (MTS) final assembly schedule is not needed as the MPS itself plans the end item.
Activities included in FAS.
The final assembly schedule serves to plan and control final assembly and test operations. The following activities are generally included in the FAS:
a) launching of final assembly orders,
b) picking of components parts,
c) sub-assembly,
d) painting or other finishing operations
e) scheduling the fabrication or purchase of any components not under MPS control but
needed in final assembly
f) packing
Product characteristics.
The final assembly schedule is usually used for products that
a) have relatively low volume
b) are highly customized
c) have short producrement or manufacturing lead-time
References.
Khalid Sheikh (2003) 'Manufacturing resource planning (MRP II): with introduction to ERP, SCM and CRM'. New York: McGraw-Hill Companies.


Lead (electronics)

In electronics, a lead  is an electrical connection consisting of a length of wire or a metal pad (surface-mount technology) that is designed to connect two locations electrically. Leads are used for many purposes, including: transfer of power; testing of an electrical circuit to see if it is working, using a test light or a multimeter; transmitting information, as when the leads from an electrocardiograph are attached to a person's body to transmit information about their heart rhythm; and sometimes to act as a heatsink. The tiny leads coming off through-hole electronic components are also often called "pins"; in ball grid array packages, they are in form of small spheres, and are therefore called "balls".
Many electrical components such as capacitors, resistors, and inductors have only two leads, while some integrated circuits can have several hundred or even more than a thousand for the largest ball grid array packages. Integrated circuit pins often either bend under the package body like a letter "J" (J-lead) or come out, down, and form a flat foot for securing to the board (S-lead or gull-lead).
Most kinds of integrated circuit packaging are made by placing a silicon chip on a lead frame, wire bonding the chip to the metal leads of the lead frame, and covering the chip with plastic. The metal leads protruding from the plastic are then either "cut long" and bent to form through-hole pins, or "cut short" and bent to form surface-mount leads. Such lead frames are used for surface mount packages with leads – such as Small Outline Integrated Circuit Quad Flat Package  – and for through-hole packages such as dual in-line package  – and even for so-called "leadless" or "nolead" packages – such as Quad Flat Noleads package.
The lead frame (and therefore the pins, if any, formed from that lead frame) are occasionally made from Invar or similar alloys, due to their low coefficient of thermal expansion.
Electrical effects.
For many circuit designs it can be assumed that the leads do not contribute to the electrical effects of individual components. However, this assumption begins to break down at higher frequencies and at very small scales. These effects come from the physical construction of the leads. The leads are often metal connections that run from the rest of the circuit to the materials that each component is made of. This design results in a very small capacitance between the ends of the leads where they connect to the device and very small inductances and resistances along each lead. Because the impedance of each component is a function of the frequency of the signals being passed through the device and the inductance and capacitance of the device the leads can cause substantial variation in the properties of components in radio frequency circuits.


Twin-carbon arc welding

Unlike single-carbon arc welding, in twin-carbon arc welding (TCAW) the arc is maintained between two carbon (graphite) electrodes held in a special holder. The Ac current was usually used. It was switched on by operating bringing two electrodes closer by a mechanism which also adjusted arc length. The two electrodes touch momentarily, then separate and thus an arc is established. TCAW is unshielded and no artificial pressure is applied.
History.
TCAW was first proposed in 1874.
Use.
The size of the arc depends upon the distance between the electrode tips, electrode diameters and the welding current. The heat input to the job can be varied by changing the arc size or the distance between the arc and workpiece. After striking the arc, welding can be carried out in the same way as in TIG welding process.
An AC supply is recommended for TCAW. In case a DC supply is used, the positive electrode will disintegrate and consume at a much faster rate as compared to negative electrode, because two-thirds of the total heat is generated at the positive anode. This will produce an unstable arc and require frequent adjustment of the electrodes. In AC welding, because of alternate reversals of polarity, both the electrodes will be affected equally and present no problem.
The electrodes employed for TCAW are approximately of the same diameter as the workpiece thickness. The magnitude of arc current required for welding depends upon both electrode diameter and plate thickness. For example, an 8 mm diameter electrode will need about 65 amps to weld a mild steel sheet of thickness 3.5 mm and 80 Amps to weld a sheet of 6 mm thickness.
TCAW, though more complex than single carbon arc welding, possesses the advantage that arc is independent of the job and can be moved anywhere without getting extinguished. Moreover, the workpiece is not a part of the electrical circuit.
While carbon electrodes have been replaced by tungsten and other alternatives in many places, in developing countries simple twin carbon-arc torches are a cheaper and more sustainable alternative to oxyacetylene torches. A simple version of a TCAW apparatus was designed in Ethiopia, it has reduced costs and improved the accessibility of welding services.


Servomotor

A servomotor (or servo motor) is a rotary actuator or linear actuator that allows for precise control of angular or linear position, velocity, and acceleration. It consists of a suitable motor coupled to a sensor for position feedback. It also requires a relatively sophisticated controller, often a dedicated module designed specifically for use with servomotors.
Servomotors are not a specific class of motor, although the term "servomotor" is often used to refer to a motor suitable for use in a closed-loop control system.
Servomotors are used in applications such as robotics, CNC machinery, and automated manufacturing.
Mechanism.
A servomotor is a closed-loop servomechanism that uses position feedback to control its motion and final position. The input to its control is a signal (either analog or digital) representing the position commanded for the output shaft.
The motor is paired with some type of position encoder to provide position and speed feedback. In the simplest case, only the position is measured. The measured position of the output is compared to the command position, the external input to the controller. If the output position differs from that required, an error signal is generated which then causes the motor to rotate in either direction, as needed to bring the output shaft to the appropriate position. As the positions approach, the error signal reduces to zero, and the motor stops.
The very simplest servomotors use position-only sensing via a potentiometer and bang-bang control of their motor; the motor always rotates at full speed (or is stopped). This type of servomotor is not widely used in industrial motion control, but it forms the basis of the simple and cheap servos used for radio-controlled models.
More sophisticated servomotors make use of an Absolute encoder (a type of rotary encoder) to calculate the shafts position and infer the speed of the output shaft. A variable-speed drive is used to control the motor speed. Both of these enhancements, usually in combination with a PID control algorithm, allow the servomotor to be brought to its commanded position more quickly and more precisely, with less overshooting.
Servomotors vs. stepper motors.
Servomotors are generally used as a high-performance alternative to the stepper motor. Stepper motors have some inherent ability to control position, as they have built-in output steps. This often allows them to be used as an open-loop position control, without any feedback encoder, as their drive signal specifies the number of steps of movement to rotate, but for this, the controller needs to 'know' the position of the stepper motor on power up. Therefore, on the first power-up, the controller will have to activate the stepper motor and turn it to a known position, e.g. until it activates an end limit switch. This can be observed when switching on an inkjet printer; the controller will move the ink jet carrier to the extreme left and right to establish the end positions. A servomotor can immediately turn to whatever angle the controller instructs it to, regardless of the initial position at power up if an absolute encoder is used.
The lack of feedback of a stepper motor limits its performance, as the stepper motor can only drive a load that is well within its capacity, otherwise missed steps under load may lead to positioning errors and the system may have to be restarted or recalibrated. The encoder and controller of a servomotor are an additional cost, but they optimize the performance of the overall system (for all of speed, power, and accuracy) relative to the capacity of the basic motor. With larger systems, where a powerful motor represents an increasing proportion of the system cost, servomotors have the advantage.
There has been increasing popularity in closed-loop stepper motors in recent years. They act like servomotors but have some differences in their software control to get smooth motion. The main benefit of a closed-loop stepper motor is its relatively low cost. There is also no need to tune the PID controller on a closed loop stepper system.
Many applications, such as laser cutting machines, may be offered in two ranges, the low-priced range using stepper motors and the high-performance range using servomotors.
Encoders.
The first servomotors were developed with synchros as their encoders. Much work was done with these systems in the development of radar and anti-aircraft artillery during World War II.
Simple servomotors may use resistive potentiometers as their position encoder. These are only used at the very simplest and cheapest level and are in close competition with stepper motors. They suffer from wear and electrical noise in the potentiometer track. Although it would be possible to electrically differentiate their position signal to obtain a speed signal, PID controllers that can make use of such a speed signal, generally warrant a more precise encoder.
Modern servomotors use rotary encoders, either absolute or incremental. Absolute encoders can determine their position at power-on but are more complicated and expensive. Incremental encoders are simpler, cheaper, and work at faster speeds. Incremental systems, like stepper motors, often combine their inherent ability to measure intervals of rotation with a simple zero-position sensor to set their position at start-up.
Instead of servomotors, sometimes a motor with a separate, external linear encoder is used. These motor + linear encoder systems avoid inaccuracies in the drivetrain between the motor and linear carriage, but their design is made more complicated as they are no longer a pre-packaged factory-made system.
Motors.
The type of motor is not critical to a servomotor, and different types may be used. At the simplest, brushed permanent magnet DC motors are used, owing to their simplicity and low cost. Small industrial servomotors are typically electronically commutated brushless motors. For large industrial servomotors, AC induction motors are typically used, often with variable frequency drives to allow control of their speed. For ultimate performance in a compact package, brushless AC motors with permanent magnet fields are used, effectively large versions of Brushless DC electric motors.
Drive modules for servomotors are a standard industrial component. Their design is a branch of power electronics, usually based on a three-phase MOSFET or IGBT H bridge. These standard modules accept a single direction and pulse count (rotation distance) as input. They may also include over-temperature monitoring, over-torque, and stall detection features. As the encoder type, gearhead ratio, and overall system dynamics are application specific, it is more difficult to produce the overall controller as an off-the-shelf module, and so these are often implemented as part of the main controller.
Control.
Most modern servomotors are designed and supplied around a dedicated controller module from the same manufacturer. Controllers may also be developed around microcontrollers in order to reduce cost for large-volume applications.
Integrated servomotors.
Integrated servomotors are designed to include the motor, driver, encoder, and associated electronics into a single package.


Machinery repairman

Machinery repairman (abbreviated as MR) is a United States Navy occupational rating. The Shop Machinist and the Outside Machinist ratings of the Machinist's Mate rating were combined to create the Machinery Repairman rating in 1948.
Machinery repairmen perform organizational and intermediate maintenance on assigned equipment and in support of other ships, requiring the skillful use of lathes, milling machines, boring mills, grinders, power hack saws, drill presses, and other machine tools; portable machinery; hand tools; and measuring instruments found in a machine shop.
Machinery repairmen are skilled machine tool operators. They make replacement parts for a ship's engine auxiliary equipment, such as evaporators, air compressors and pumps. The repair of deck equipment, including winches and hoists, condensers and heat exchange devices are completed by machinist mates. Machinery repairmen assist enginemen by repairing or producing parts in the machine shop. Shipboard machinery repairmen do not frequently operate main propulsion machinery, primarily performing machine shop duties.


Jarden Zinc Products

Jarden Zinc Products LLC. has been manufacturing continuous casting zinc strip since the late 1800s. The company is a subsidiary of One Rock Capital. The company is most notable for being the sole manufacturer of planchets used in the production of the United States penny. Jarden Zinc is also the manufacturer of the ZincSecure based Ukrainian ₴5 and ₴10 coins.
Products.
The company's largest source of revenue comes from the production of coin blanks, having produced over 300 billion blanks at their Tennessee facility. The company also supplies zinc strips used in various cathodic protection, building, automotive, architectural, and specialty products. Such products include zinc galvanic anodes, LifeJacket, and LifeDowel automotive blade fuses, metal flashing, guttering systems, plumbing hardware, wall cladding, braille, organ pipes, counter tops, signs, and medals among other niche items.
Product development.
Zinc's attributes and characteristics can be manipulated to create new zinc alloys. Jarden Zinc Products has a product development team that is tasked with creating new alloys that meet specific market needs.


GlobeCore

GlobeCore is a manufacturer and vendor of industrial equipment for production of bitumen emulsions, modified bitumen, oil regeneration and oil purification, fuel blending, biodiesel production, wet milling and nonoblending. Its headquarters are in Oldenburg, Germany.
About company.
GlobeCore’s spectrum of services ranges from metal cutting to assembling of processing units. GlobeCore has facilities in several countries, including the United States, the UAE, and South Africa. Technical assistance to customers is provided by 17 dealer agencies worldwide.
Products.
The following is a list of processing units manufactured by GlobeCore:
Services.
The company maintains, repairs and updates its own equipment and provides training for the customer's service staff.
Customers.
GlobeCore serves the following companies and industries:


Selective heat sintering

Selective heat sintering (SHS) is a type of additive manufacturing process. It works by using a thermal printhead to apply heat to layers of powdered thermoplastic. When a layer is finished, the powder bed moves down, and an automated roller adds a new layer of material which is sintered to form the next cross-section of the model. SHS is best for manufacturing inexpensive prototypes for concept evaluation, fit/form and functional testing. SHS is a Plastics additive manufacturing technique similar to selective laser sintering (SLS), the main difference being that SHS employs a less intense thermal printhead instead of a laser, thereby making it a cheaper solution, and able to be scaled down to desktop sizes.


Multiple lining tool

The multiple lining tool is a burin chisel used in engraving with multiple cutting blades for making parallel lines to create a hatching effect.
The multiple lining tool is also called the multiple tool, lining tool, multiliner, liner, shooter, multiple graver, comb, and half-tone comb.
Description.
The multiple lining tool allows the engraver to create hatched shading effects by engraving multiple parallel lines at the same time. It achieves this by having two or more cutting blades, which are available in different grades or sizes, such as the density of lines. The resulting hatching has a mechanical look.


Adrian Hobbs

Charles Adrian Hobbs (born January 1946, in Ilkley, West Yorkshire, UK) specialises in vehicle crashworthiness with a background in accident and injury investigation/analysis.
As an engineer and later as Honorary Chief Research Scientist, Hobbs was involved in the UK Government’s programme of Crash Injury Research for nearly 30 years. He undertook the research that helped lead to the mandatory wearing of the seat belt in the UK, the development of the Offset Deformable Frontal Barrier Crash Test and the establishment of the safety organisation Euro NCAP. Hobbs was awarded a C.B.E. in 2008.
Hobbs has provided advice to the World Bank (1), the World Health Organization, the European Commission and Central European and North African countries on transport safety and the provision of emergency services (2-4).
Safety career.
Hobbs joined the Transport Research Laboratory (TRL) in 1972 as a Scientific Officer. For two years he was involved in researching accident causation, investigating accidents alongside the police about the contributing factors to an accident. (5,6) In 1976 he reported on his analysis of brake defects and their contribution to accidents (7).
In 1974, he shifted his focus to car occupant injuries. He analysed and reported on the direct connection between the accident, resulting injuries, their causes and the effectiveness of safety features with medical data, car inspection and questionnaires. During this period he concluded that intrusion into the passenger compartment of the vehicle during a frontal impact accident played a very major role in causing injuries. (8-10)
As a result of this research, he realised how effective wearing a seat belt was in preventing serious injury to a vehicle’s occupant. In 1978, Adrian published a comprehensive study of the life-saving potential of seat belt wearing.(11-14) This study helped lead to the passing of the mandatory seat belt wearing legislation in the UK (Hansard), which came into force on 31 January 1983. (15)
Hobbs then switched his research focus to vehicle safety and, in 1985, he designed a demonstration Pedestrian Safety Car (based on a Mini Metro). (16-21), later modified to incorporate current thinking in Frontal and Side impact protection. (22,23) For side impact, conventional wisdom held that protection came from strengthening the side of the car and providing padding protection on the inside of the door. Hobbs expressed his concern that many manufacturers were simply fitting door beams, located where they could increase the risk of injury. (24-31) Hobbs's modifications did improve the car, but the car still did not provide good protection or meet the proposed side impact test requirements. Elsewhere in France, Germany, and the UK another vehicle was tested. Hobbs researched about this car, which although much weaker than the modified Metro, performed better. He discovered that a lighter door rather than a heavier door bounces off the impacting car and starts moving the occupant earlier, increasing the time the body has to absorb the impact, so reducing the severity of injuries. He also discovered that when the door is controlled to move in vertically, it spreads the load over the chest, abdomen and pelvis consequently avoiding its concentration on the vulnerable chest area, reducing the possibility of a fatal injury. The provision of padding, Hobbs also concluded, had to be very soft to help spread the load and cushion the impact. (32-35) These conclusions and research directly contributed to the development of the European Side Impact Directive.
In the early 1990s, Hobbs identified the inadequacies in the current frontal crash test procedure and his research led to the development of the Offset Deformable Barrier (ODB) Frontal Impact Crash Test. (36-52). Hobbs's frontal ODB test was adopted, in Europe and elsewhere, for both legislation and consumer test programmes.
With this research under his belt, Hobbs took on the study of Compatibility, the science of how cars could work together to minimise injuries to the occupants of both vehicles. (53-57) Although the research identified what needed to be changed and an assessment procedure was developed, research funding dried up and government interest in further improving car crash safety was absent.
Europe.
During the 1990s, Hobbs was an active member of the European Experimental Vehicles Committee (EEVC) in particular of the Frontal Impact and the Compatibility Working Groups, which he initiated. He also collaborated with other working groups to develop test procedures for side impact and pedestrian protection.
Hobbs was asked by the European Transport Safety Council (ETSC) to present the case for the adoption of the EEVC Frontal and Side Impact test procedures for European Type Approval to the European Parliament in Strasbourg. The EEVC was proposing an initial crash test speed of 56 km/h (approx. 30 mph) rather than the 60 km/h already used in research crash tests. The intention was that the test speed would later be increased to 60 km/h. This was at a European Parliament Inter-group meeting, with Max Mosley of the Federation Internationale de L’Automobile (FIA) as chairman. Industry was there to oppose – their concern was that cars could not be built to withstand the speeds proposed. Yet Max Mosley, profoundly moved by the recent death of Ayrton Senna on the race track, developed an increased interest in reducing the road accident injury toll. The death of a racing driver had spurred on the cause to improve car safety for the public and to prevent millions of deaths on European roads.
A new consumer information programme.
Meanwhile, back in the UK Hobbs had been working on a proposal for an independent crash test programme called UK NCAP. His proposal, presented in 1994, outlined to the UK department of Transport the concept of a consumer information programme based on the EEVC proposed frontal impact, side impact and pedestrian protection crash test procedures. His reason for a consumer-based information car-testing programme was clear. He cited the New Car Assessment Programme in the US that had had a more significant effect on changing car design than any US legislative test. He also cited the magazine Auto Motor und Sport and the ADAC, in Germany, whose published car crash tests results were already influencing how manufacturers designed their cars, as they endeavoured to obtain good ratings in the published tests.
The Department of Transport agreed to go ahead with the proposal and initiated the first phase of tests and assessments. (58-60) Following further discussions with the European Commission, in Brussels, (61,62) Hobbs mentioned the proposal to Max Mosley. Mosley was inspired to help and make Hobbs’s wish for a Europe wide consumer test programme a reality. Called initially the UK NCAP programme it later came to be branded, with the support of the FIA and other European players, as Euro NCAP.
EURO NCAP.
Euro NCAP (the European New Car Assessment Programme) is now an established consumer-testing programme that assesses and publishes the safety of new cars and provides valuable safety information to consumers. Thousands of crash-tested cars later and the award of thousands of stars to industry, Euro NCAP has led to the establishment of other similar consumer programmes across the world and has contributed greatly to the safety of cars available on the European market.
Yet it all began with Hobbs’s persistence and a group of dedicated safety pioneers. The inaugural meeting of Euro NCAP was held in December 1996 with only a few members: the UK Department of Transport, the FIA, the Swedish National Road Association (SNRA) and International Testing. The very first results of 7 crash-tested super-minis were released publicly to the media in early 1997, much to the consternation of industry. (63-67)
Hobbs was the first Chairman of the Technical Working Group and he later became Secretary General until his retirement in 2007.
Euro NCAP’s team of engineers and labs now carry out a frontal, side impact and pedestrian protection test as well as assessments on child protection and on the range of technologies existing within the car. Tests are carried out on all vehicles from super-minis to SUVs to the latest hybrids and petrol engines, resulting in a star rating with a maximum award of 5 stars. Special awards are also given to car makers with innovative technologies.
Safety achievements and developments in the industry, as a direct result of the work of Euro NCAP, have included the following:
For frontal impact protection: improved car structures limiting passenger compartment intrusion, so providing space for the restraints to operate without the occupants impacting the car’s interior, improved seat belts with pre-tensioners and load limiters, improved multi-stage frontal airbags, removal of hazards in the knee impact area and knee protecting air bags.
For side impact protection: improved car side structures with airbags to protect the head, chest, abdomen and pelvis, and pole impact protection.
Additional achievements have been: car fronts with improved pedestrian protection, improved child occupant protection, provision of effective reminders to wear seat belts, promotion and greater introduction of technologies such as electronic stability controls, autonomous emergency braking and lane departure warnings.
Personal life.
Hobbs continues to provide consultancy on road and vehicle safety issues and provides advice to the media. He is a motor sport enthusiast having been a rally driver in his youth. Since retirement, he has become involved in supporting a number of local and national organisations. Since 1974, he has been married to Jacqueline, a retired teacher with a keen focus on special needs. Their adopted son Philip died in 2002, aged 28. Adrian and Jackie live together in Berkshire.
References.
Other selected publications


2018 Niger Cup

The 2018 Coupe nationale du Niger is the 43rd edition of the Coupe nationale du Niger, the knockout football competition of Niger.
Round 1.
[May 20]
Entente FC (Dosso) lt Akokana FC d' Arlit (Agadez)
[May 22]
Representant de Zinder lt AS Université AM (Niamey)
AS Garde Nationale (Niamey) 5-0 Wombeye FC (Maradi)
AS Forces Armées Nigériennes (Niamey) lt US Gendarmerie Nationale (Niamey)
[May 23]
Soniantcha FC (Tillabery) lt Dan Gourmou (Tahoua)
Jangorzo FC (Maradi) 8-1 Espoir FC (Zinder)
Olympic FC (Niamey) 1-1 AS Douanes (Niamey) [3-4 pen]
Urana FC d' Arlit (Agadez) bt Arewa FC de Doutchi (Dosso)
AS Forage (Niamey) 1-4 Racing FC (Niamey)
Azzura FC (Zinder) 0-3 Sahel Sporting Club (Niamey)
[May 24]
Atlantique (Maradi) 0-3 ASN NIGELEC (Niamey)
AS ZAM (Niamey) bt AS Tsunami FTC (Niamey)
National Dendi (Dosso) 0-7 JS Tahoua
[May 25]
Nassara de Tessaoua (Maradi) 0-8 Nassara AC (Agadez)
[Jun 6]
Lantarki (Agadez) lt AS SONIDEP (Niamey)
Barka FC (Diffa) lt AS Police (Niamey)
Round 2.
[Jun 10]
US Gendarmerie Nationale (Niamey) 0-1 Racing FC (Niamey)
[Jun 12]
AS Douanes (Niamey) 0-0 AS Police (Niamey) [4-5 pen]
AS SONIDEP (Niamey) 2-1 AS ZAM (Niamey)
[Jun 13]
Urana FC d' Arlit (Agadez) drw AS Université AM (Niamey) [AS Université on pen]
Nassara AC (Agadez) 1-3 Jangorzo FC (Maradi)
[Jun 16]
JS Tahoua 0-1 Sahel Sporting Club (Niamey)
ASN NIGELEC (Niamey) 2-1 Dan Gourmou (Tahoua)
[Jun 17]
AS Garde Nationale (Niamey) 2-1 Akokana FC d' Arlit (Agadez)
Quarterfinals.
[Jul 7]
AS Garde Nationale (Niamey) 2-1 AS SONIDEP (Niamey)
[Jul 8]
AS Université AM (Niamey) 0-2 Racing FC (Niamey)
Sahel Sporting Club (Niamey) 1-3 Jangorzo FC (Maradi)
[Jul 10]
ASN NIGELEC (Niamey) drw AS Police (Niamey) [5-3 pen]
Semifinals.
First leg
[Jul 15]
Jangorzo FC (Maradi) 2-3 Racing FC (Niamey)
[Jul 19]
ASN NIGELEC (Niamey) 0-1 AS Garde Nationale (Niamey)
Second leg
[Jul 22]
AS Garde Nationale (Niamey) 2-0 ASN NIGELEC (Niamey) [3-0 agg]
[Jul 26]
Racing FC (Niamey) 2-1 Jangorzo FC (Maradi) [5-3 agg]
Final.
[Aug 3, Stade Régional, Maradi]
AS Garde Nationale (Niamey) 0-0 Racing FC (Niamey) [5-4 pen]


Fan-out wafer-level packaging

Fan-out wafer-level packaging (also known as wafer-level fan-out packaging, fan-out WLP, FOWL packaging, FO-WLP, FOWLP, etc.) is an integrated circuit packaging technology, and an enhancement of standard wafer-level packaging (WLP) solutions.
In conventional technologies, a wafer is diced first, and then individual dies are packaged; package size is usually considerably larger than the die size. By contrast, in standard WLP flows integrated circuits are packaged while still part of the wafer, and the wafer (with outer layers of packaging already attached) is diced afterwards; the resulting package is practically of the same size as the die itself. However, the advantage of having a small package comes with a downside of limiting the number of external contacts that can be accommodated in the limited package footprint; this may become a significant limitation when complex semiconductor devices requiring a large number of contacts are considered.
Fan-out WLP was developed to relax that limitation. It provides a smaller package footprint along with improved thermal and electrical performance compared to conventional packages, and allows having higher number of contacts without increasing the die size.
In contrast to standard WLP flows, in fan-out WLP the wafer is diced first. But then the dies are very precisely re-positioned on a carrier wafer or panel, with space for fan-out kept around each die. The carrier is then reconstituted by molding, followed by making a redistribution layer atop the entire molded area (both atop the chip and atop the adjacent fan-out area), and then forming solder balls on top.


Honing (metalworking)

Honing is an abrasive machining process that produces a precision surface on a metal workpiece by scrubbing an abrasive grinding stone or grinding wheel against it along a controlled path. Honing is primarily used to improve the geometric form of a surface, but can also improve the surface finish.
Typical applications are the finishing of cylinders for internal combustion engines, air bearing spindles and gears. There are many types of hones, but all consist of one or more abrasive stones that are held under pressure against the surface they are working on.
Other similar processes are lapping and superfinishing.
Honing stones.
Honing uses a special tool, called a "honing stone" or a "hone", to achieve a precision surface. The hone is composed of abrasive grains that are bound together with an adhesive. Generally, honing grains are irregularly shaped and about 10 to 50 micrometers in diameter (300 to 1500 mesh grit). Smaller grain sizes produce a smoother surface on the workpiece.
A honing stone is similar to a grinding wheel in many ways, but honing stones are usually more friable, so that they conform to the shape of the workpiece as they wear in. To counteract their friability, honing stones may be treated with wax or sulfur to improve life; wax is usually preferred for environmental reasons.
Any abrasive material may be used to create a honing stone, but the most commonly used are corundum, silicon carbide, cubic boron nitride, and diamond. The choice of abrasive material is usually driven by the characteristics of the workpiece material. In most cases, corundum or silicon carbide are acceptable, but extremely hard workpiece materials must be honed using superabrasives.
The hone is usually turned in the bore while being moved in and out. Special cutting fluids are used to give a smooth cutting action and to remove the material that has been abraded. Machines can be portable, simple manual machines, or fully automatic with gauging depending on the application.
Modern advances in abrasives have made it possible to remove much larger amount of material than was previously possible. This has displaced grinding in many applications where "through machining" is possible. External hones perform the same function on shafts.
Process mechanics.
Since honing stones look similar to grinding wheels, it is tempting to think of honing as a form of low-stock removal grinding. Instead, it is better to think of it as a self-truing grinding process.
In grinding, the wheel follows a simple path. For example, in plunge grinding a shaft, the wheel moves in towards the axis of the part, grinds it, and then moves back out. Since each slice of the wheel repeatedly contacts the same slice of the workpiece, any inaccuracies in the geometric shape of the grinding wheel will be transferred onto the part. Therefore, the accuracy of the finished workpiece geometry is limited to the accuracy of the truing dresser. The accuracy becomes even worse as the grind wheel wears, so truing must occur periodically to reshape it.
The limitation on geometric accuracy is overcome in honing because the honing stone follows a complex path. In bore honing, for example, the stone moves along two paths simultaneously. The stones are pressed radially outward to enlarge the hole while they simultaneously oscillate axially. Due to the oscillation, each slice of the honing stones touch a large area of the workpiece. Therefore, imperfections in the honing stone's profile cannot transfer to the bore. Instead, both the bore and the honing stones conform to the average shape of the honing stones' motion, which in the case of bore honing is a cylinder. This averaging effect occurs in all honing processes; both the workpiece and stones erode until they conform to the average shape of the stones' cutting surface. Since the honing stones tend to erode towards a desired geometric shape, there is no need to true them. As a result of the averaging effect, the accuracy of a honed component often exceeds the accuracy of the machine tool that created it.
The path of the stone is not the only difference between grinding and honing machines, they also differ in the stiffness of their construction. Honing machines are much more compliant than grinders. The purpose of grinding is to achieve a tight size tolerance. To do this, the grinding wheel must be moved to an exact position relative to the workpiece. Therefore, a grinding machine must be very stiff and its axes must move with very high precision.
A honing machine is relatively inaccurate and imperfect. Instead of relying on the accuracy of the machine tool, it relies on the averaging effect between the stone and the workpiece. Compliance is a requirement of a honing machine that is necessary for the averaging effect to occur. This leads to an obvious difference between the two machines: in a grinder the stone is rigidly attached to a slide, while in honing the stone is actuated with pneumatic or hydraulic pressure.
High-precision workpieces are usually ground and then honed. Grinding determines the size, and honing improves the shape.
The difference between honing and grinding is not always the same. Some grinders have complex movements and are self-truing, and some honing machines are equipped with in-process gauging for size control. Many through-feed grinding operations rely on the same averaging effect as honing.
Economics.
Since honing is a high-precision process, it is also relatively expensive. Therefore, it is only used in components that demand the highest level of precision. It is typically the last manufacturing operation before the part is shipped to a customer. The dimensional size of the object is established by preceding operations, the last of which is usually grinding. Then the part is honed to improve a form characteristic such as surface finish, roundness, flatness, cylindricity, or sphericity.
Performance advantages of honed surfaces.
Since honing is a relatively expensive manufacturing process, it can only be economically justified for applications that require very good form accuracy. The improved shape after honing may result in a quieter running or higher-precision component.
The flexible honing tool provides a relatively inexpensive honing process.
This tool produces a controlled surface condition unobtainable by any other method. It involves finish, geometry and metallurgical structure. A high-percentage plateau free of cut, torn and folded metal is produced. The flexible hone is a resilient, flexible honing tool with a soft cutting action. The abrasive globules each have independent suspension that assures the tool to be self-centering, self-aligning to the bore, and self-compensating for wear.
Cross-hatch finish.
A "cross-hatch" pattern is used to retain oil or grease to ensure proper lubrication and ring seal of pistons in cylinders. A smooth glazed cylinder wall can cause piston ring and cylinder scuffing. The "cross-hatch" pattern is used on brake rotors and flywheels.
Plateau finish.
The plateau finish is one characterised by the removal of "peaks" in the metal while leaving the cross-hatch intact for oil retention. The plateaued finish increases the bearing area of the finish and does not require the piston or ring to "break in" the cylinder walls.
Plateau honing specification:
A profilometer provides modern, defined descriptions of cylinder bore finish that include “RPK” (Reduced Peak Height), “RVK” (Reduced Valley Depth) and “RK” (Core Roughness Depth), which is based on both the “RPK” and “RVK” measurements.


Overlay control

In silicon wafer manufacturing overlay control is the control of pattern-to-pattern alignment necessary in the manufacture of silicon wafers.
Silicon wafers are currently manufactured in a sequence of steps, each stage placing a pattern of material on the wafer; in this way transistors, contacts, etc., all made of different materials, are laid down. In order for the final device to function correctly, these separate patterns must be aligned correctly – for example contacts, lines and transistors must all line up.
Overlay control has always played an important role in semiconductor manufacturing, helping to monitor layer-to-layer alignment on multi-layer device structures. Misalignment of any kind can cause short circuits and connection failures, which in turn impact fab yield and profit margins.
Overlay control has become even more critical now because the combination of increasing pattern density and innovative techniques such as double patterning and 193 nm immersion lithography creates a novel set of pattern-based yield challenges at the 45 nm technology node and below. This combination causes error budgets to shrink below 30 percent of design rules, where existing overlay metrology solutions cannot meet total measurement uncertainty (TMU) requirements.
Overlay metrology solutions with both higher measurement accuracy/precision and process robustness are key factors when addressing increasingly tighter overlay budgets. Higher order overlay control and in-field metrology using smaller, micro-grating or other novel targets are becoming essential for successful production ramps and higher yields at 45 nm and beyond.
Examples of the widely adopted overlay measurement tools worldwide are KLA-Tencor's ARCHER , and the nanometrics CALIPER series, overlay metrology platforms.


Punch (tool)

A punch is a tool used to indent or create a hole through a hard surface. They usually consist of a hard metal rod with a narrow tip at one end and a broad flat "butt" at the other. When used, the narrower end is pointed against a target surface and the broad end is then struck with a hammer or mallet, causing the blunt force of the blow to be transmitted down the rod body and focused more sharply onto a small area. Typically, woodworkers use a ball-peen hammer to strike a punch.
Use.
Punches are used to drive fasteners such as nails and dowels, making a hole, or forming an indentation/impression of the tip on a workpiece. Decorative punches may also be used to create a pattern or even form an image.
Pin.
Metal pins and similar connectors are driven in or out of holes using a pin punch.
For removal, first use a starter punch to loosen the pin, then use a pin punch to finish.
Center.
A "center punch" is used to mark the center of a point. It is usually used to mark the center of a hole when drilling holes. A drill has the tendency to "wander" if it does not start in a recess. A center punch forms a large enough dimple to "guide" the tip of the drill. The tip of a center punch has an angle between 60 and 90 degrees. When drilling larger holes, where the drill bit is wider than the indentation produced by a center punch, the drilling of a pilot hole is usually needed.
An automatic center punch operates without the need for a hammer.
Prick punch.
A "prick punch" is similar to a center punch but used for marking out. It has a sharper angled tip to produce a narrower and deeper indentation. The indentation can then be enlarged with a center punch for drilling. The tip of a prick punch is 60 degrees (the angle depends on what type of prick punch one is using). It is also known as a dot punch.
Transfer.
A "transfer punch" is a punch (usually in an index set) of a specific outer diameter that is non-tapered and extends the entire length of the punch (except for the tip). It is used to tightly fit the tolerances of an existing hole and, when struck, precisely "transfer" the center of that hole to another surface. It can be used, for example, to duplicate the hole patterns in a part, or precisely set locations for threaded holes (created by drilling and tapping) to bolt an object to a surface.
Drift.
A "drift "punch"" is misleadingly named; it is not used as a punch in the traditional sense of the term. A drift punch, or drift pin, or lineup punch, is used as an aid in aligning bolt or rivet holes prior to inserting a fastener. A drift punch is constructed as a tapered rod, with the hammer acting on the large end of the taper. The long end of a drift punch is placed into the semi-aligned bolt holes of two separate components, and then driven into the hole. As it is driven in, the taper forces the two components into alignment, allowing for easy insertion of the fastener. Unlike most punches, force is never (and should never be) applied to the tip, or end of a drift pin.
Roll pins.
Roll pin punches are used to drive roll pins. Standard pin punches should never be used on a roll pin. Because of the hollow, thin wall construction of a roll pin, a standard pin punch will often collapse, mar or distort the end of the pin or be driven into, and jammed inside, the hollow core of the roll pin. When choosing a roll pin punch, select one that is no larger than the compressed diameter of the pin. If a punch is used that is larger than the pin, the surrounding metal in which the pin is seated can be damaged. Also, a roll pin punch should not be used which is smaller than the compressed diameter of the pin. If this occurs, it may be possible to drive the punch through the hollow center of the roll pin.
Roll pin punches are designed with a small projection in the center of the pin tip to support the circumference of the roll pin. The tips of roll pin punches are not flat and should never be used on regular solid pins. If a roll pin punch is used on a solid pin, it will mar or mark the pin.
If the end of a roll pin punch is damaged or deformed, it should be discarded. It is virtually impossible to regrind the tip of the roll pin punch and properly shape the center projection.
When using a roll pin punch, make sure the axis of the shank of the roll pin punch is in line with the axis of the roll pin. Do not cant the roll pin punch off to one side. When you strike the roll pin punch, hit it directly on the top of its head. If you strike the head of the roll pin punch at an angle you may bend the shank.
Decorative.
Punches with a decorative motif have been used to create patterns or images on metals and various other materials, notably leather. In goldsmithing, bookbinding and armor-making the technique is called pointillé. In printmaking punches were used to create most of the image in the plates for printing metalcuts.
Letter.
Also known as "letter stamps" or "number stamps", letter punches are used to emboss the impression of a letter or number into a workpiece. They are most common in the reverse image, this allows the end result to be immediately readable, regardless they may be made as a positive image. This is essential in the case of die or mold making and ensures that the finished product will be readable, as a die is a negative image.
Tablet press.
These punches are a part of tablet press. Unlike most punches, tablet press punches have a concave ending in the shape of the desired tablet. There are the lower and the upper punches to compress the powder in between.


Laser converting

For industrial processes, Laser converting or laser digital converting is a production technology that enables device manufacturers to produce features that otherwise would be problematic or even impossible to die-cut, without the need for tooling.
In contrast to traditional mechanical converting, laser digital converting utilizes the features of lasers and advance software technology to convert parts in extremely high accuracy. In production environment, the laser digital converting is the economics of scale when the production run is short, as there is virtually no 'up-front' cost associated with machine tools making and storage. Also, the turnaround time is minimal as it only involves software interpretation on the imported engineering diagram of the part.


AQSIQ-Registration for the Export of Recycling Material to China

The “Registration of Overseas Supplier of Imported Scrap Materials“ is required for Non-Chinese companies for importing industrial waste and recycling parts into China. The application has to be submitted at the AQSIQ (General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Chinese: 中华人民共和国国家质量监督检验检疫总局). The registration is mandatory for all Non-Chinese exporters. Aim of this registration is to monitor the import of potential environmental harmful material and ensure that no material is imported into China that are not in compliance with the Chinese environment standards.
If companies are not registered, parts will be detained in customs and no import process is possible. In addition to the registration of the exporting companies, the parts have to be registered with the CCIC (China Certification & Inspection Group; Chinese 中国检验认证集团), and, furthermore, these parts will be accordingly inspected.
Products requiring registration.
The following products require this registration


Outline of manufacturing

The following outline is provided as an overview of and topical guide to manufacturing:
Manufacturing – use of machines, tools and labor to produce goods for use or sale. Includes a range of human activity, from handicraft to high-tech, but most commonly refers to industrial production, where raw materials are transformed into finished goods on a large scale.
History.
Origins of manufacturing.
Industrial Revolution
Emergence of the factory.
Factory
Improvement of industrial processes.
Industrial process
Operations of manufacturing.
Modern manufacturing processes.
Taxonomy of manufacturing processes
Manufacturing process management


Mask shop

A mask shop is a factory which manufactures photomasks for use in the semiconductor industry. There are two distinct types found in the trade. Captive mask shops are in-house operations owned by the biggest semiconductor corporations, while merchant mask shops make masks for most of the industry.
Merchant mask shops will produce photomasks for a variety of integrated device manufacturers (IDMs), foundries or optical device companies in addition to providing excess cavity work and re-pellicle for captive mask shops.
The company structure is similar to that of any medium-sized manufacture and has the
following unique departments or mask makers:
Photomask market.
The worldwide photomask production market was $3.1 billion in 2013. Almost half of market attributed to captive mask shops (in-house mask shops of major chipmakers).
Infrastructure (technical and financial).
The costs of creating new mask shop for 180 nm processes were estimated in 2005 as $40 million, and for 130 nm - more than $100 million. In 2013 cost of new 28 nm mask shop was estimated at $110 – 140 million.
Future.
As technology shrinks, the cost to mask shops increase and the product turn around time grow longer as well. The trend in this new decade is for manufacturing to migrate eastwards to reduce cost and lead times. Once technology restrictions in the Wassenaar Arrangement are reduced, high end reticles and integrated circuits will be produced in mainland China
rather than Taiwan.


Cimier

Montres Cimier SA is an independent Swiss watch manufacturer whose headquarters is in Biel, Switzerland. Cimier produces mechanical watches as well as quartz watches.
History.
The origin of Cimier goes back in 1924 when the mukesh watchmaker Joseph Lapanouse founded his company Lapanouse SA in Hölstein and sold his watches first under the brand Rego and later Cimier. Since the beginning, Joseph Lapanouse specialised in manufacturing pin-pallet watches, called Roskopf.
In the 1950s, the company, that became in the meantime Lapoanouse-Cimier SA, industrialized the first pin-pallet escapement chronograph sold at 21 million pieces during its lifetime. At the end of the 1960s the annual production reached 1.5 million pieces and the company employed over 500 people in Bubendorf.
In the 1970s, the watch industry experienced the quartz crisis. The number of mechanical watches sold was drastically reduced. Cimier developed and industrialized its own quartz movement. However, the number of pieces produced did not reach the threshold of profitability. As a result, in 1985, the Swiss manufacturer decided to temporarily cease production.
In 2003, the brand Cimier was reborn through the company which has the same name.
In 2010, Cimier opened the Watch Academy. The concept allowed customers to create and build their own watch in Cimier's workshop. The customer can choose between several manual movements and an automatic movement.


Coil zipper

Coil zipper—also known as nylon coil zipper—is a type of zipper whose teeth/elements are made from that is traditionally nylon. The coil is sewn to a zipper tape to make the final product. The final zipper product is completed when the nylon coiled teeth are sewn onto the zipper tape. Nylon coil zippers have a continuous coil chain made from nylon. When this coil is positioned on the back of the zipper and not in the front, this kind of zipper is called invisible zipper.
Design.
Nylon zippers are highly flexible and are available in a wide range of sizes. The high compatibility of the coil zippers is the main attribute for their huge number of applications in fashion wear, canvas goods, and bags. These types of zippers are also the top choice for the outdoor and luggage industries. Nylon coil zippers are most commonly found in tents, suitcases, backpacks, and other camping apparels.
Though nylon coil zippers are a popular choice for a large number of applications, the use of nylon is now being replaced with polyester. Polyester coil zippers are also becoming widespread. They are made in various gauge sizes and colors. This makes them well-suited to several use cases.
Benefits.
Coil zippers offer higher horizontal strength . Coil zippers are also easier to repair; an out-of-alignment tooth can be realigned simply by zipping and unzipping past it. Another advantage of nylon zippers is its two-way functionality. The sliders can be fixed in either direction of the zipper chain and they will can still function smoothly. Nylon is lightweight, heat resistant and rustproof, making nylon coil zippers durable and reliable.
Manufacturing.
The main elements required in the manufacturing process of coil zipper are a stringer, slider, and a tab. The stringer consists of a tape and teeth assembly. The tab is used to pull the slider up and down which opens and closes the zipper.


Circular procurement

Circular procurement is an approach that recognises the role that private and public authorities can play in supporting the transition towards a circular economy. Circular procurement can be defined as the process by which private or public authorities purchase works, goods or services that seek to contribute to closed energy and material loops within supply chains whilst minimising, and in the best case avoiding, negative environmental impacts and waste creation across their whole life-cycle. As a concept, it builds on Sustainable Procurement, adding elements such as closed-loop material use.
Policy context.
The EU Action Plan for the Circular Economy has established an ambitious programme of action which will help to ‘close the loop’ of product lifecycles. This plan recognises public procurement as a key driver in the transition towards the circular economy, and it sets out several actions that the European Commission will take to facilitate the integration of circular economy principles in GPP. These include highlighting circular aspects in new or updated sets of EU GPP Criteria.
Circular public procurement also has a role in achieving the Sustainable Development Goals, defined by the United Nations 2030 Agenda for Sustainable Development. Especially, SDG 12 - Responsible Consumption and Production – includes a specific target on promoting sustainable public procurement practices, in accordance with national policies and priorities.
Furthermore, several countries, regions, and cities have been developing their circular strategies in which public procurement is often emphasized as a key mechanism for scaling up the transition to a circular economy.
Three Levels of Circular Procurement.
There are three types or ‘levels’ of models for implementing circular procurement:
Benefits.
Besides sustainable procurement, circularity can help buyers take a more comprehensive approach - from the first stages of procurement to the end of product life – while achieving financial benefits. A circular economy will retain materials at their highest value, push for innovation and support local employment markets. By 2025, at a global scale, it has an estimated potential to add $1 trillion to the global economy and create 100,000 new jobs within the next five years.


Joern Meissner

Joern Meissner (born c. 1970) is a German academic, business consultant, entrepreneur and Professor of Supply Chain Management & Pricing Strategy at Kühne Logistics University in Hamburg.
Biography.
Meissner received MA in Business Management in 1997 at the University of Hamburg, and his Ph.D. in Management Science in 2005 from the Columbia Business School under the supervision of Professors Awi Federgruen and Costis Maglaras.
He is a current lecturer in the Management Science Department at the Lancaster University Management School and also lectures at the University of Hamburg and the University of Manheim, and has taught at Handelshochschule Leipzig (the Leipzig Graduate School of Management).
Meisser hold the position of Professor of Supply Chain Management & Pricing Strategy at Kuehne Logistics University in Hamburg. Prof. Meissner is active in the area of Supply Chain Management, Dynamic Pricing, and Revenue Management.
He is the founder of Manhattan Review, a multi-national test prep, MBA admissions consulting, and career training company.
Work.
Meissnerhas been published in various journals including Manufacturing and Service Operations Management (MSOM); Operations Research; Naval Research Logistics; European Journal of Operational Research, and written several book chapters.
He has also been featured in BusinessWeek for Manhattan Review’s Communications Bootcamp with Columbia Business School. Newsweek, The Independent, The Times, Handelsblatt and Frankfurt Allgemeine Zeitung have also quoted Prof. Meissner regarding the GMAT and MBA admissions.
His paper “Dynamic pricing strategies for multiproduct revenue management problem," jointly written with Costis Maglaras, was a finalist in the MSOM Best Paper award 2009. He frequently advises companies ranging from Fortune 500 companies to emerging start-ups on various issues related to his research.


MTConnect

MTConnect is a manufacturing technical standard to retrieve process information from numerically controlled machine tools. As explained by a member of the team that developed it, "This standard specifies the open-source, royalty-free communications protocol based on XML and HTTP Internet technology for real-time data sharing between shopfloor equipment such as machine tools and computer systems. MTConnect provides a common vocabulary with standardized definitions for the meaning of data that machine tools generate, making the data interpretable by software applications." A simple, real-world example of how this tool is used to improve shop management is given by the same author.
History.
The initiative began as a result of lectures given by David Edstrom of Sun Microsystems and David Patterson, professor of Computer Science at the University of California, Berkeley (UCB) at the 2006 annual meeting of the Association for Manufacturing Technology (AMT). The two lectures promoted an open communication standard to enable Internet connectivity to manufacturing equipment.
Initial development was carried out by a joint effort between the UCB Electrical Engineering and Computer Sciences (EECS) department, the UCB Mechanical Engineering (ME) department (both in the College of Engineering) and the Georgia Institute of Technology, using input from industry representatives. The resulting standard is available under royalty-free licensing terms.
Description.
MTConnect is a protocol designed for the exchange of data between shop floor equipment and software applications used for monitoring and data analysis. MTConnect is referred to as a read-only standard, meaning that it only defines the extraction (reading) of data from control devices, not the writing of data to a control device. Freely available, open standards are used for all aspects of MTConnect. Data from shop floor devices is presented in XML format, and is retrieved from information providers, called Agents, using Hypertext Transfer Protocol (HTTP) as the underlying transport protocol. MTConnect provides a RESTful interface, which means the interface is stateless. No session must be established to retrieve data from an MTConnect Agent, and no logon or logoff sequence is required (unless overlying security protocols are added which do). Lightweight Directory Access Protocol (LDAP) is recommended for discovery services.
Version 1.0 was released in December 2008.
The first public demonstration of MTConnect occurred at the International Manufacturing Technology Show (IMTS) held in Chicago, Illinois September 2008. There, 25 industrial equipment manufacturers networked their machinery control systems, providing process information that could be retrieved from any web-enabled client connected to the network.
Subsequent demonstrations occurred at EMO (the European machine tool show) in Milan, Italy in October 2009, and the 2010 IMTS in Chicago.
Standard.
The MTConnect standard has three sections. The first section provides information on the protocol and structure of the XML documents via XML schemas. The second section specifies the machine tool components and the description of the available data. The third and last section specifies the organization of the data streams that can be provided from a manufacturing device. The MTConnect Institute is considering adding a fourth section to support mobile assets that include tools and work-holdings.
MTConnect took an incremental approach to defining the requirements for manufacturing device communications. It did not exhaustively define every possible piece of data an application can collect from a manufacturing device, but it works forward from business and research objectives to define the required elements to meet those needs. The standard catalogued important components and data items for metal cutting devices. MTConnect provides an extensible XML schema to allow implementors to add custom data to meet their specific needs, while providing as much commonality as possible.
On September 16, 2010, The MTConnect Institute and the OPC Foundation announced cooperation between the respective organizations.
Applications.
The maintenance cost and losses in productivity with unplanned downtime for machine tool components such as spindle bearings and ball screws could be reduced if one could proactively take action prior to failure. In addition, cutting tools and inserts are expensive to replace when they are still in good condition, but replacing the tools too late can be costly due to scrap and re-work. The proposed health monitoring application will use MTConnect to extract controller data and pattern recognition algorithms to assess the health condition of the spindle and machine tool axes. The health assessment approach is based on running a routine program each shift in which the most recent data patterns are compared to the baseline data patterns. An online tool condition monitoring module is also proposed and uses controller data such as the spindle motor current, with other add on sensors (vibration, acoustic emission) to accurately estimate and predict tool wear. With the added transparency of the machine tool health information, one can take proactive actions before significant downtime or productivity losses occur.


Custom-fit

Custom-fit means personalized with regard to shape and size. A customized product would imply the modification of some of its characteristics according to the customers requirements such as with a custom car. However, when fit is added to the term, customization could give the idea of both the geometric characteristics of the body and the individual customer requirements, "e.g.", the steering wheel of the Formula 1 driver Fernando Alonso.
The custom-fit concept can be understood as the idea of offering one-of-a-kind products that, due to their intrinsic characteristics and use, can be totally adapted to geometric characteristics in order to meet the user requirements.
With this new concept, industry moves from a resource based manufacturing system to a knowledge based manufacturing system and from mass production to individual production. This encourages the Lean Production trend as established by Toyota, or in other words, an efficiency-based production.
Research.
There are some studies referring to the positive impacts this concept would have on society:
The research studies found in February 2008 on the subject are the following:
Technical Tools.
Data Capturing.
The process starts with the capturing of data directly from the user by CAD techniques with the ultimate aim of manufacturing products using CAM techniques.
Process Design and Validation.
Although all these developments have been of great interest, the RM-processes have not fallen behind, due to improvement of new Rapid Prototyping Direct digital manufacturing techniques.
Rapid Manufacturing Systems, Tools and Materials.
MPP aims to become the equivalent of a high speed 3D-printer that produces three-dimensional objects directly from powder materials. This technique is based on the process principles of xerographic printers, (for example, laser or LED printers) that combine electrostatic printing with photography. The MPP process approach uses the same fundamental principles to build solid objects on a layer-by-layer basis. Layers of powder materials are generated by attracting different metal- and/or ceramic powders to their respective position on a charged pattern on a photoreceptor by means of an electrostatic field. The attracted layer is transferred to a punch and transported to the consolidation unit where each layer of part material is sintered onto the previous by pressure and heat. The procedure is repeated layer-by-layer until the three-dimensional object is fully formed and consolidated.
MPP has the ability to print different powders within the same layer and progressively change from one material to another, i.e., producing a functionally graded material. In addition to this, MPP uses external pressure to speed the densification process (sintering), which allows manufacturing with a wide range of materials and opens the possibility to produce unique material combinations and microstructures.
It has several print heads that produce continuous streams of material droplets at high frequency. The High Viscosity Inkjet Printing machine is also capable of printing multi-materials simultaneously and also enables the mixing and grading of materials in any combination that is desired. This will enable the manufacturing of products with two or more materials that are graded and there will be no distinct boundary between the materials. This will result in products with unique mechanical properties.
Dr. Michiel Willemse who is leading the project says, "The process is unique in its capability to print highly viscous, UV curable, resins. Material formulations with viscosities up to 500 mPa•s (at ambient temperature) have been printed successfully. This offers the opportunity to print products with unequaled mechanical properties when compared to any other printing systems."


Castrol India

Castrol India Limited is an automotive and industrial lubricant manufacturing company. Castrol India is the 2nd largest manufacturer of automotive and industrial lubricants in the Indian lubricant market and owns around 20% market share in the overall Indian lubricant market. It is part of Castrol Limited UK (part of BP Group). It has 5 manufacturing plants that are networked with 270 distributors, serving over 70,000 retail outlets.
History.
In 1910, Castrol India started importing certain automotive lubricants from C C Wakefield & Company made an entry in the Indian market. In 1979, CIL was incorporated under the name of Indrol Lubricants and Specialities Pvt Ltd. It was listed on BSE in 1982 and CIL was converted into a public limited company. CIL had formed a subsidiary Company in the year 1987 under the name of Indtech Speciality Chemicals, Ltd.
On 1 November 1990, the name of the company was changed from Indrol Lubricants & Specialities Ltd. to Castrol India Ltd. It helped to manufacture of Telephone cable jellies, pharmaceuticals jellies and industrial waxes in technical collaboration with Dussek Campbell, U.K.
As of December 2019, there were talks ongoing between Reliance Industries and BP for setting up fuel stations in India where Castrol's products will be sold.
Products.
Corrosion preventives, industrial lubricants, metalworking fluids, high temperature grease,cutting oil, automotive oil, neat cutting oil, cleaners


Plant layout study

A plant layout study is an engineering study used to analyze different physical configurations for a manufacturing plant. It is also known as Facilities Planning and Layout.
Overview.
The ability to design and operate manufacturing facilities that can quickly and effectively adapt to changing technological and market requirements is becoming increasingly important to the success of any manufacturing organization. In the face of shorter product life cycles, higher product variety, increasingly unpredictable demand, and shorter delivery times, manufacturing facilities dedicated to a single product line cannot be cost effective any longer. Investment efficiency now requires that manufacturing facilities be able to shift quickly from one product line to another without major retooling, resource reconfiguration, or replacement of equipment.
Investment efficiency also requires that manufacturing facilities be able to simultaneously make several products so that smaller volume products can be combined in a single facility and that fluctuations in product mixes and volumes can be more easily accommodated. In short, manufacturing facilities must be able to exhibit high levels of flexibility and robustness despite significant changes in their operating requirements.
In industry sectors, it is important to manufacture the products which have good quality and meet customers’ demand. This action could be conducted under existing resources such as employees, machines and other facilities. However, plant layout improvement, could be one of the tools to response to increasing industrial productivity. Plant layout design has become a fundamental basis of today’s industrial plants which can influence parts of work efficiency. It is needed to appropriately plan and position employees, materials, machines, equipment, and other manufacturing supports and facilities to create the most effective plant layout.
The intended products to be manufactured influence the choice of layout.


Coherence scanning interferometry

Coherence scanning interferometry (CSI) is any of a class of optical surface measurement methods wherein the localization of interference fringes during a scan of optical path length provides a means to determine surface characteristics such as topography, transparent film structure, and optical properties. CSI is currently the most common interference microscopy technique for areal surface topography measurement. The term "CSI" was adopted by the International Organization for Standardization (ISO).
The technique encompasses but is not limited to instruments that use spectrally broadband, visible sources (white light) to achieve interference fringe localization. CSI uses either fringe localization alone or in combination with interference fringe phase, depending on the surface type, desired surface topography repeatability and software capabilities. The table below compiles alternative terms that conform at least in part to the above definition.


Beam lead technology

Beam lead technology is a method of fabricating a semiconductor device. Its initial application was for high-frequency silicon switching transistors and high-speed integrated circuits. This technology eliminated the labor-intensive wire-bonding process that was commonly used for integrated circuits at the time. It also enabled the automated assembly of semiconductor chips onto larger substrates, facilitating the production of hybrid integrated circuits.
History.
In the early 1960s, M.P. Lepselter developed techniques for fabricating a structure that involved electroforming an array of thick, self-supporting gold patterns on a thin film Ti-Pt-Au base, leading to the term "beams." These patterns were deposited on the surface of a silicon wafer. The excess semiconductor material beneath the beams was subsequently removed, resulting in the separation of individual devices and leaving them with self-supporting beam leads or internal chiplets cantilevered beyond the semiconductor material. These contacts not only served as electrical leads but also provided structural support for the devices.
Patents.
Patented inventions included:
Legacy.
This technology, also known as air-bridge technology, has established itself for its unsurpassed reliability in high-frequency silicon switching transistors and ultra-high-speed integrated circuits for telecommunications and missile systems. The beam lead devices, produced by the hundreds of millions, became the first example of a commercial microelectromechanical structure (MEMS).


Renault AX

The Renault AX is an automobile manufactured by Renault. It was produced between 1908 and 1914 and was mostly used by cab drivers.
The AX had a 2-cylinders straight engine with a displacement of 1,060 cc and a power of 8 kW. Its maximum speed was 35 mph (56 km/h). The vehicle weighed 750 kg.