Economic-statistical design of ARMA chart for an integrated production and maintenance model in presence of multiple assignable causes, rework process, and random failures

This study proposes a simultaneous design of production planning, maintenance strategy, and control chart from an economic-statistical viewpoint. For more adaptation with the real applications, the possibility of occurrence of multiple assignable causes and equipment failure are taken into consideration. Furthermore, to reduce production costs, a rework process is carried out on the non-conforming items right after the regular production cycle. An auto-regressive moving average (ARMA) control chart is designed to monitor the autocorrelated process. In addition, three types of maintenance activities are implemented based on system conditions to restore the process to an as-good-as-new situation. Finally, four comparative studies are conducted to investigate the importance of the model characteristics. The first one studies the effect of the rework process on cost saving. The second one confirms the importance of the process monitoring on the production rate of conforming items. The third study demonstrates the necessity of taking equipment failure into account. The last one exhibits the significant effect of the ARMA control chart on out-of-control run length and consequently quality loss cost.