Runner System Design Optimization for Multigated and Multicavity Injection Molds

Runner system design for injection molds with multiple gates or multiple cavities often requires iterative analyses for optimized results, because the gate locations or cavity shapes may not be naturally balanced. In addition, in molds with symmetrical layouts, the required injection pressure may be unnecessarily high if the runners are poorly sized. In this paper, a scheme for quickly optimizing runner system design is presented. The objective of design optimization is to minimize the required injection pressure within the design space defined by a given total runner volume. Each runner segment can be given an upper limit and lower limit to define the range of runner cross sectional dimensional size. Application examples are included to demonstrate the effectiveness of the scheme.