Iraj Mahdavi - Mazandaran University of Science & Technology, Babol, Iran
Morteza Bagherpour - Mazandaran University of Science & Technology, Babol, Iran
S.Majid Ebrahimi - Mazandaran University of Science & Technology, Babol, Iran

Master production schedule (MPS) and material requirements planning (MRP) are used for production planning. The objective of this study is to determine the proper lot size in order to increase delivery performance by adjusting priority delay, processing delay, staging delay and requirements delay. The approach used in this paper, is to present the multi-product production planning problem with a bill of materials (BOM) as a network. This representation helps in calculating various delays. Further, the impact of change of lot size on the adjustment of the delays can be easily evaluated using the network and the Gantt chart prepared from the network.

MPS, MRP, Lot Size, Priority Delay, Processing Delay, Staging Delay, Requirements Delay