Abstract:
This research proposed a master production scheduling method for automotive airbag manufacturing with minimizing the backorder quantity, holding cost, and transportation cost between production plant and warehouse as objectives. The master production plan of the case study company is the weekly production plan with 52 planning horizontal periods. The plan consisted of the production quantity of 238 airbag models on 38 production lines. Forecasting data of demand, production capacity for each week, and production constraint of airbag models corresponding to each production line were used as input data for master production planning by using experience of planner. If the production quantity was less than the corresponding demand, then the backorder occurred. While the holding cost and the transportation cost occurred in case that excessive production quantity was scheduled. The mathematical programming model for generating master production plan with minimizing backorder quantity and holding cost was proposed to solve this problem. The transportation cost between production plant and warehouse was calculated after the master production plan was created. The master production plan generated from the proposed method was compared to the previous method. The results revealed that the mathematical programming model can generate the master production plan where the backorder was decreased from 27% to 6.2% of demand and the total cost of holding and transportation was decreased by 31%. The holding cost was increased by 10% since the inventory was increased for backorder occurring prevention. The minimum production capacity setting for each week as an input data for the proposed model was also accounted in the exceeding holding cost.