Defects that occur due to turbulent filling of the casting cavity coupled with air entrainment during filling lead to defects that severely reduce mechanical and physical properties of castings. A lowering of fatigue strength, UTS, and elongation are commonplace, and are often combined with loss of pressure tightness, difficulty in machining and cosmetic imperfections. The mechanisms that form these defects are briefly summarized and methods of minimizing or even eliminating the variables that cause the problems are described and explained. The paper goes on to show how this knowledge was applied to a specific casting where failure under high-pressure tightness is unacceptable. The case study describes a pressure cooker that due to the environment in which it is used must pass certain UL standards for a pressure vessel that will be detailed in the paper. The history of this casting and filling methods is described, and the modifications to the gating are explained using simulation. Not only is a technical case made for the resulting filling system but the economic arguments for this optimized filling process that produces both reliable and consistent castings is presented.
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