Optimum parting line design of molded and cast parts for manufacturability

Abstract This paper presents a methodology for obtaining an optimal design of a mold tool for an injection molded or a diecast part based on part geometry. The methodology uses multiobjective function criteria. It considers how parting line complexity, draw depth, number of undercuts, number of unique side cores, and mold complexity affect manufacturability and cost. The design variables selected for this problem are draw direction range and parting line location. The draw direction range limits possible parting line locations to those not associated with undercuts. These design variables can be extracted from the part geometry by dividing the surfaces into concave and convex regions. The concave and convex regions determine the allowable draw range and parting line location for the part, respectively. A nonlinear programming technique generates the optimal mold configuration solution. This paper presents an example that generates the optimal mold configuration for a typical molded part using the described methodology.