Process planning optimization for the manufacture of injection moulds using a genetic algorithm

This paper reports a real application of a computeraided process planning (CAPP) system, IMOLD_CAPP, for the manufacture of injection moulds. A combination of a template and a generative approach is used for the development of this CAPP system. The input to the system is the three-dimensional mould components developed by IMOLD. Here, the process-types and their sequences for a particular type of mould component are defined in the plan template based on company practice, while selection of machine tools, cutting tools, and cutting conditions for different processes in the plan template are optimized by a method based on genetic algorithms (GAs). The objective function of optimization is to minimize overall processing time. The performance of the optimization is compared with an algorithm based on simulated annealing (SA), and the GA-method is found to be appropriate for the optimization. This approach is expected to be applicable in most mould shops based on their available machining resources.