Integrated Production Planning and Preventive Maintenance Model with Non-fixed Lead Time

Non-fixed lead time in production planning is a challenge issue especially in high utilization systems such as semiconductor wafer manufacturing system. Also, the mutual influence between production planning and preventive maintenance should be integrated to achieve overall optimization. In this paper, preventive maintenance's influence on production planning is considered based on the existing non-fixed lead time clearing function. An integrated production planning and preventive maintenance model is built to reflect the mutual influence between production planning and preventive maintenance. Experiments are conducted by simulation under different production line complexity and facility degradation levels. As a result, the superiority of the integrated model is demonstrated compared to two existing production planning models.