成组方式下考虑故障率限制的生产调度模型

Production scheduling model considering failure rate threshold for group production

针对成组生产方式下的单机加工系统,提出一类考虑设备故障率限制的生产调度优化模型,以贴近实际加工情况。该优化模型以最小化总完工时间和总维护成本为目标,除考虑与相似度相关的生产设置时间和加工零件的学习遗忘效应外,还考虑了设备劣化效应,并采用预防性维护和小修相结合的混合维护方式,基于故障率阈值,采取适当的预防性维护以有效避免维护不足或过量,对于批量加工过程中的设备突发故障则采用基于役龄的小修。根据优化模型的数学特征,利用遗传算法求解模型。通过算例数值结果表明所提出的优化模型可在避免维护不足或过量的同时,进一步减少维护成本和缩短完工时间。

Aiming at the single machine system in group production,an improved production scheduling model considering failure rate was proposed.To minimize total completion time and total maintenance cost,the model adopted the deterioration effect besides similarity-dependent setup time and learning and forgetting effect.A hybrid maintenance strategy combined preventive maintenance and minimal repair was researched,in which failure rate threshold was considered to perform preventive maintenance and unexpected failure was considered to perform minimal repair based on machine＇s usage.Genetic algorithm was adopted to solve this integrated model.Through a case study,the computation results demonstrated that this optimization model could reduce the maintenance cost and shorten the completion time more effective without maintenance loss.