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Winning Designs Demonstrate the Best in Castings

May 29, 2005
Quality, ingenuity, design excellence, and value were the winning characteristics of the 2005 casting competitions.

The North American Die Casting Association (NADCA) presented awards for the best diecast part designs of 2005 at CastExpo ‘05 in St. Louis, in mid April. The International Die Casting Competition is held annually, and NADCA states that this year’s winning diecastings showed the versatility of aluminum, zinc, and magnesium diecast parts, ranging from a 1-oz. reverse valve to a 61-lb transaxle cover.

The combination of quality, ingenuity, design excellence, and value in the finished part were common among all the winners, as was the contribution to expanding the market for castings.

“The entries in the 2005 competition prove that North American diecasters are continuing to push the frontiers for parts that improve finished products, reduce assembly time, and contribute to the overall success of manufacturers,” said NADCA president Daniel Twarog. “A great deal of this success is the result of diecasters and manufacturers working as partners to develop effective solutions.”

ABM Manufacturing’s latch for a folding table produced for All Steel Inc. is a two-piece design, replacing a three-piece assembly that required five unique parts. The part, the winning entry for aluminum under one pound, reduced tooling, part, and assembly costs. The innovative design feature incorporates break points into the part so that it could be modified by hand on the assembly line for use with two smaller-sized tables. The casting also allowed the plastic handle to snap-fit onto the latch, making assembly easier.

Imperial Die Casting won the award for the aluminum 1-10 lb category. Their design, a complex diesel engine oil filter housing, incorporates multiple functions in a near-net shape part that maintained flatness within 0.014 inch for the bottom-mating surface. It includes oil flow passages, ports for oil temperature and pressure sensors, a turbocharger oil supply port, and bosses for mating the filter housing to other parts. Judges noted that Imperial worked closely with the customer to make a number of recommendations to improve the castability of the part, including changes in the radii, relocation of the parting line, elimination of some thin tool-steel sections, and minimizing the number of ejection pins which reduce the need for flash removal.

For aluminum over 10 lbs, Walker Die Casting was recognized for its transaxle case for a consumer vehicle. The 61-lb high-pressure aluminum casting replaces an iron part that was sand-cast. In addition to reducing weight by using a lower cost raw materials, the judges cited several other benefits, including better casting tolerances reducing final machining requirements and several elements of the case that could be used as a cast rather than needing to be machined. These improvements resulted in faster cycle times that reduced the overall project cost, compared with other processes.

In the non-automotive, over 10 lb aluminum category, Bardane Manufacturing Co. was the winner for its impeller used in commercial and industrial blowers. Produced for Amertek Rotion, it also replaces a sand casting. Several advantages cited by the judges include the ability to produce a more complex configuration while reducing weight and porosity. The result is a quieter, faster-turning impeller that requires less motor power to spin it.

DeCarty Die Casting’s Snap-On heavy-duty air impact wrench won in the zinc under six ounces, non-electroplated class. The valve body (one inch long and one ounce in weight) has seven different functions. The part requires tight tolerances within tenths of a mil along critical mating surfaces and minimal machining to simplify assembly, reducing production costs. This entry was selected because it met the rigid requirements in a cost-effective way, and couldn’t be matched by other means of production.

Winning in the over six ounces, non-electroplated category for zinc was Dero Enterprises and their snow-stop roof bracket, produced for Roofer’s Annex. The 2-lb SnoStop bracket supports snow and ice barriers installed on steel covered roofs. The cast part replaces a stamped steel piece, providing greater strength and a more reliable overall shape. Zinc will not corrode if the painted part is chipped, adding more cost savings.

The winning entry for magnesium under 0.5 lb was Phillips Plastics Corporation’s fishing reel frame for Marsh Technologies. The frame replaces plastic or aluminum parts from previous designs. Weighing just 31 grams, the reel is lighter than aluminum and offers exceptional part density and surface quality, unmatched by plastic. Other advantages noted by the judges were the ability to allow complex geometry with varying wall thickness while maintaining tight tolerances of bores and surfaces for mating components.

AFS Fifth Annual Casting Competition/B>

CastExpo’s other host, the American Foundry Society, held its annual Casting Competition, recognizing nine cast components as top designs of 2005. Castings were entered from several industries, including automotive, military, medical, and aeronautical.

The Casting of the Year was awarded to ME Global (Elecmetal) of Duluth, MN, for its crawler transporter, which carries the NASA Space Shuttle to its launch pad. The component weighs 2,200 lbs and measures 7.5 3 1.5 ft. It is made of modified 4320 steel and cast using the V-process. While search for the right design combination, ME Global poured over 40 castings to identify the alloy and manufacturing process that could be repeated for suitable shoes.

Four “Best In Class” awards were presented. Aristo-Cast was recognized for its windshield wiper motor components. By using magnesium for the six main motor components, 75% of the space was saved, weight decreased by 25%, and noise levels were reduced.

Burnstein von Seelen Precision Castings Corp. won for its Jam Nut, by converting a 68-lb solid billet to a 17 lb machined permanent mold casting, used in seismic instrumentation for drilling apparatus.

Denison Industries’ Elevation Housing “Turtle” was honored. Denison converted the component, used in radar on U.S. Navy vessels, using a no-bake molding, now a process requiring just three cast assemblies, instead of the original machining and welding 90 individual components.

General Motors Powertrain’s winning entry was the LS7 Dry Sump Oil Tank, using three molded polystyrene foam slices in the lost foam process. It maximizes oil volume in limited packaging space and eliminates several internal leak paths.

Five honorable mentions were recognized. A.L. Johnson Co. won for its laser housing for electronics and cooling systems. Piad Precision Casting Corp. earned the honors for its Push Arm to lift and support the front mower deck on a zero turning radius. Mercury Marine’s Verado L6 Four-Stroke Cylinder Head for an outboard engine is comprised of a automotive-style cylinder head coupled with a double-water jacketed exhaust manifold. The Dotson Co. won for its Gooseneck Trailer Hitch Conversion Kit, a stronger connection to a fifth- wheel hitch with minimal machining.