Injection mold maintenance scheduling with Mold-Lifting crane consideration

Abstract

Injection mold maintenance scheduling is a challenging problem in plastics production systems. On one hand, it harmonizes the production activities on machines and molds. On the other hand, it decides when maintenance activities should be performed in order to improve the reliability of production systems. In the previous studies [1, 2], a Joint Scheduling (JS) approach was proposed to deal with some mold maintenance scheduling problems. It was shown that the JS approach outperforms the traditional Maximum Age (MA) approach. However, the models had not considered the capacity of mold-lifting crane which is likely to be the bottleneck of mold maintenance activities. Therefore, in this paper, a new problem is modeled with the consideration of the capacity of mold-lifting crane. A genetic algorithm approach is applied to deal with this new problem. The numerical examples show that considering the mold-lifting crane, the JS approach can still outperform the MA approach and obtain the shortest makespan.