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Top Honors in ICIs Annual Casting Contest

Nov. 2, 2009
A large number of entries makes for some difficult decisions in the Investment Casting Institutes 2009 design competition.

In conjunction with the Investment Casting Institute’s annual technical conference and expo, the ICI has announced the winners of its investment casting contest. “We had more entries this year than ever before, and consequently, competition was very stiff,” said ICI’s executive director Michael Perry. “For the first time, two awards were given for defense. It was simply impossible to chose only one in this category.”

Joining defense in the contest design categories were aerospace and industrial products. The four winning entries in these categories took top honors. Additionally, seven finalists were recognized, too.

The contest is open to members of the Investment Casting Institute. It was established to recognize on an annual basis the plants that manufacture components that best illustrate and promote the benefits and flexibility of the investment casting process, or that demonstrate problem-solving techniques for the customer.

Top of the list

Recognized as the 2009 winner in the aerospace division, Alcoa Howmet’s (Georgetown, ON) — a perennial contestant in the ICI program, and a frequent honoree. The 12 11.5 16-in. component includes multiple complex internal passages that are necessary to control fuel flow in a commercial aircraft jet engine. Cast of Aluminum C35, it features 11 intricate internal passages, formed by proprietary shellbuilding techniques — without the use of ceramic coring. The part is currently in production and helps Alcoa achieve low cost and low-weight requirements for the customer.

Dameron Alloy Foundries (Compton, CA) was the winner in the industrialcasting category This is a complex casting functions as a part within a part. The intricate stainless steel body casting/roll seal valve is used for marine, industrial, waterworks, and ground fueling purposes. The part has a complex internal ‘grid’ (seen here in its wax mold) enabling the finished part to function as designed. The grid feature is uniform around the internal diameter. It is very difficult to access, and the cost and difficulty of rework in this area may be prohibitive.

The new valve replaces a welded assembly of castings and machined parts. It is cast in 316L stainless steel or Monel, depending on the application. During the conversion from welded assembly to the casting, special attention was focused on wall thickness, grid design, and ‘mating’ of the two structures. Special problem-solving techniques, such as proprietary drying techniques, were used to successfully produce the part.

The first of two winners in the defense category, O’Fallon Casting (O’Fallon, MO) demonstrated its ability to combine multiple parts and features into a single piece. The electronics housing unit measures 7.5 7.5 10-in. and is cast in A356-T6 aluminum. The design is highly complex and incorporates a number of attributes, such as undercuts, lightening pockets, card-guard slots, heat-sink fins, mounting features, thin walls (0.060-in.), and demanding tolerances. It is lighter and of higher precision than a comparable fabrication of multiple parts, minimizing the amount of secondary machining required to finish the part.

Another repeat winner, Uni-Cast/Cera-Met (Bethlehem, PA) was recognized in the defense category for its large aluminum casting that provides the customer with cost savings over selecting fabricated or fully machined components. Measuring 27 24 24-in., it serves as a support structure for military targeting. It features multiple thick-to-thin sections, as well as Grade B X-ray and no-weld zones.

ICI Design Contest Finalists
Precision Castings of Tennessee (Gallatin, TN) Cable-Tite
The system consists of three investment castings: anchor, cap, and top plate. Using IC4140 alloy, it also features ribbing to maximize the strength of the castings. There are alignment notches around the anchor cap to indicate that the pieces are locked and in pretensioned position, and a feature at the bottom of the plate to assure no-slip contact with wood.

FENICO Precision Castings Inc. (Paramount, CA)
Crankcase model
The complexity of the part required investment casting, in this case, of A356-T6 aluminum. The entry measured 11-in. long, or … scale model. The full sized piece was used on many aircraft in WWII.

TechCast Inc. (Myerstown, PA)
K-nut

This piece, cast in F357 AMS 4289, measures 6 6 2.5-in., replaces a 7-piece fabrication and weldment. No assembly is required with the new version, and it is lighter in weight. The customer is able to cast its logo in the part as well.

Aristo-Cast Inc. (Almont, MI)
Medical device for laporoscopic surgery
Cast in 316L stainless steel, there are several components in the assembly. The parts have extremely thin walls and slots — some measuring 0.040 in. The stationary jaw has a 0.040 diameter hidden blind hole through two interior walls that can’t be machined.

TPM Inc. (Sugar Land, TX)
Split coupling used in protection valves
Previously machined from bar stock (taking 18 hours), this saves time and money. Cast in WCB, CA- 15, and brass, it measures 3 3 4-in. and weighs 40% less than its predecessor.

SeaCast (Marysville, WA)
Ice Spike sole plate for Olympic footware
Specifically designed for footwear used in Olympic competition, the selection of In718 or T16-4 to cast the part affords lighter weight and improved performance, as well as improved spike sharpness.

Wisconsin Precision Casting (East Troy, WI)
Core tube for heat exchanger
Replaces a multiple-piece weldment, this casting of Inconel 625 measures 1.5 8 3-in. The spirals on the outside of the piece are now cast, rather than machined.