The Wells Manufacturing Co. of Woodstock, Ill., pioneered the continuous cast iron process, which avoids problems of sand casting. Here, bars emerge from the die and are beginning to cool.

According to Matt Grander, iron product manager at A.M. Castle & Co. in Franklin Park, Ill., engineers sometimes discount iron because of the problems that sand casting process creates, including porosity, sand inclusions, pattern shift, and high pattern costs. One sand casting pattern for the molten metal can cost as much as $20,000, he said. On the other hand, iron avoids the machining difficulties encountered with low-carbon steel, and iron has greater capability for vibration dampening, which is an advantage for metal gear manufacturers, for example.

Continuous casting is a process that yields higher-quality iron in bars that are machinable, removes the sand casting problems, and in fact takes out expensive patterns altogether, Grander said. Castle distributes this iron produced by Wells Manufacturing Co. in neighboring Woodstock, Ill.

With continuous casting, the liquid metal is pulled through a water-cooled, graphite die that is machined to form the shape of the bar and mounted on a bar machine crucible. As the bar is pulled horizontally from the crucible, the ferrostatic head pressure feeds the molten iron core, producing a fine-grain cast iron that does not suffer from the shrinkage, gas holes, and sand that casting yields. A refined cooling process allows for annealing while the iron cools.

Grander noted that low-carbon steel is still preferred where extensive welding is required, or there will be a low machine-to-material ratio. Alloy steels come in for those applications requiring a level of strength and durability that cannot be provided by low-carbon steel, gray, or ductile iron.

A.M. Castle provides the continuous cast iron bars to Dynamic Engineering of Watertown, S.D. Terry Ching, a material buyer at Dynamic, says the company has found that its customers making fluid power systems are increasingly turning to continuous cast iron for their hydraulic cylinder pistons, glands, valves, manifolds, rotors, and other components.

The Automatic division of Spirol International Corp. designs and builds these pin sorters for its sister divisions that make several varieties of assembly pins. The sorter removes any damaged or bent pins, so they do not end up packaged and in customers' hands, or in their assembly gear.

The pins are fed from a Spirol series 2000 vibratory feed system through customized gauging bushings. The bushings are the classic way of checking components like pins for quality; the bushing is sized exactly to the desired output size. If a bent or deformed pin tries to pass the bushing, it can't because it won't fit. An automatic arm clears the bushing and relegates the defective pin to the scrap heap. Conventionally, this is done by an operator, according to Phil Cyr, Spirol's VP for automation.

Cyr said it is critical to ensure that customers do not receive defective pins because they can jam assembly equipment. Precise Products makes slotted pins for sale to manufacturers of products ranging from surgical staplers to cosmetics cases. Another sister division makes coiled pins.

Cyr oversaw the 12-month development—rendered using Autodesk AutoCAD software—of this generation of the sorting system. Spirol accounts for the sorters that go to its manufacturing divisions as sales by the Automatic division. Cyr intends now to have more outside sales.

Exhaust gases run through a catalytic converter. The "converter" is a substrate coated with a platinum-family metal catalyst that removes hydrocarbons, oxides of nitrogen, and carbon monoxide.

The substrate has the same proprietary extruded cordierite-ceramic composition as previous generations of the material. But 900/2 is different. The new substrate has greater surface area for the conversion process to occur, in a smaller unit volume. Corning said conventional substrate has 400 cells per square inch, but the new material has 900 cells per square inch, hence the first number in the product's name.

The "2" refers to the thickness of the channels' walls in the material, which are 0.002-inch thick. Conventional substrate materials have walls 0.0065-inch thick. Thinner walls let exhaust gases flow more easily, because there is less resistance inherent in the material; the design keeps useful energy inside the system. The material has less mass overall, and so takes less time to reach its optimum reaction, or "light-off," temperature.

Light-off occurs around 300°C and continues at much higher temperatures; the material is built to withstand spikes between 1,200° and 1,400°C. Because it is ceramic, its strength increases with heat, so the material is twice as strong at 1,200°C as it is at ambient temperature. Time to light-off is important, because catalytic conversion does not occur until the key temperature is reached and the harmful gases are released into the atmosphere during that time.

For the actual reaction, the Corning converter substrates are coated with a catalyst that is either platinum or a member of the same chemical family, including palladium or rhodium (or some combination of these metals). Companies specializing in coating substrates include AlliedSignal Corp., Johnson Matthey, Engelhard, and Degussa. According to Corning, catalytic converter coating application is the chief use of platinum in the world; jewelry is second.

After the metal makers, the active materials are canned into the part that is built into your car. Notable names in that step include Faurecia, Walker, Eberspaecher, and Arvin.

Corning believes that automakers will begin using the substrate before even tighter federal requirements kick in by 2004. Some suppliers plan to use it this fall. Corning invented the original ceramic catalytic converter substrate about 25 years ago; perhaps a half-dozen companies are involved in supplying substrates today.

Dubois Ltd. solved engineering obstacles in this Swivel Y breathing apparatus with the Carilon aliphatic polyketone material from Shell Chemicals.

The Dubois Gaunt Medical Products division was able to use the polymers to make a Swivel Y apparatus that was encountering commercial difficulty in its previous rigid plastic, and rubber and metal forms.

Prior to the introduction of the Gaunt Swivel Y, the Y-piece connectors were either fixed, rigid plastic components, or were adjustable metal and rubber devices that were heavy and often restricted airflow because of poor internal design, Dubois said.

Carilon allows the use of lips and undercuts for snap-fit assembly without the risk of damage or distortion to the finished product. The polymers' relatively high lubricity lets the joint move, but ensures a leak-free fit.

Carilon polymers are tough (a separate application is for tie belts around undersea fiber optic cable) and resistant to chemicals. They can be sterilized under gamma rays for reuse.

The Swivel Y evolved through numerous redesigns and was just about taken off the market before Dubois investigated the Shell polymers. With the change to Carilon, the product was able to return to the market.

"If we had not been able to fix the Swivel Y design, we would have had to withdraw completely from the market, writing off approximately $300,000 in tooling costs and losing considerable credibility," said Anthony Fraser, sales and marketing director for Dubois.

Keith Stone, a Shell Chemicals development engineer, and other Shell engineers worked with Dubois engineers to develop the optimum molding process. The use of Carilon reduced cycle time for Dubois and earned the company an exclusive distribution deal with Pall Medical, one of the largest medical device manufacturers.

"Our final design is a cost-effective disposable component with the functionality of a heavy reusable Y piece, but at the cost of a disposable fixed Y," Dubois's Fraser said.

According to Shell, Carilon has a unique set of physical properties. Carilon, Shell said, is stronger and stiffer, and performs over a broader temperature range than traditional materials such as polyamides and polyacetals. It is said to be less permeable to hydrocarbons than competing materials, and resistant to many aggressive chemicals.

Carilon is available in extrusion grades and several injection molding grades, including glass-reinforced, flame-retardant, mineral-filled, and lubricated compounds. The polymers can be processed on conventional molding and extrusion equipment, and their fast setup (Carilon can come palletized) can lead to reduced cycle times in injection molding applications.

Pro-Fusion, a new company in Newbury Park, Calif., is offering the technology and services to use preground and other specialty electrodes for optimal precise scale welding.

High-quality electrode materials with exact tip geometry tolerances offer a noticeable difference in precision at the arc to produce higher-quality welds with much longer electrode life. One supplier of these products and services is Pro-Fusion, a new company founded by Bernard Mannion and Jack Heinzman III in Newbury Park, Calif.

Mannion earlier held senior positions at Process Welding Systems, Weldlogic Inc., and Dimetrics/Merrick Engineering. Heinzman was president of Diamond Ground Products.

Their new company will begin by offering preground welding electrodes, tungsten electrode grinders, several tungsten alternatives, and a new line of plasma welding torches. Pro-Fusion also offers job shop welding services and machine shop services.

Pro-Fusion's customer, J&J Precision of Thomaston, Conn., offers contract welding that can involve sealing the ends of small tube diameters. J&J makes eyelets and performs stamping, forming, machining, grinding, and assembly of precision metal components.

J&J's owner, John Maxwell, investigated the latest arc welding technology not as a joining, but as a heating and sealing, procedure. By using precision preground electrodes with a micro-arc welding system, Maxwell was able to seal the tube by momentarily imposing a welding arc on its ending. This melted the tube and produced a smooth hemispherical surface. The preground electrodes ensure accuracy and repeatability, according to Pro-Fusion. J&J uses the same technology for rod and wire end rounding, welding of custom endings to tubes, and creation of ball endings on wire.

Mannion said that other applications of this type include repetitive welds on identical parts, quality or critical-function welds, and parts with significant accumulated value prior to welding.

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