O'Fallon Casting's submission into the 2018 American Foundry Society's Casting Contest won a Best in Class Award.
The number and complexity of the internal core passages in this casting allow our customer to decrease the overall size and number of pieces in the manifold assembly. Instead of multiple pieces with less complex geometries being assembled together, this one piece investment casting saves them weight and eliminates future failure points at the assembly location.
The manifold casting contains seven interconnected core passages throughout the inside of the casting, with varying diameters and depths. The combination of thin walls in certain areas, large masses of metal in others and the grade B metallurgical requirements make this casting a challenge, something ideally suited for the investment casting process.
Along with the intricate core passage areas, the casting has a very tight profile tolerance, grade B metallurgy and high pressure tightness requirements. To access the internal core passages, weld plug openings were incorporated into the design. The original design for this casting had as many as nineteen openings that needed to be welded shut prior to delivering the casting. Through the investment casting process and design optimizations, O’Fallon Casting was able to help the customer reduce the number of weld openings to four, which saved the customer cost and provided a more robust product.
The manifold casting is an excellent example of the investment casting process. The multiple core passages, tight tolerances and grade B metallurgical requirements make investment casting the ideal process for creating this part. The ability of the process to take what would have to be multiple parts in a different process and turn them into one casting really makes the investment casting process the right choice for this part.
See the article in Modern Casting here.