Research On Production Planning And Scheduling For Axle-Housing Products With Hybrid Production Style

With the development of the market, customers are requiring diversified customized products which are expensive to stock for companies and therefore, production system is changing from stock oriented manufacturing to multi- varieties and small-batch production. In China, in order to improve competitiveness and meet customers' needs, many enterprises are converting themselves from make-to-stock to make-to-order. Moreover, companies are trying to find proper planning methods to shorten the manufacturing lead-time and improve the response speed to customers.In the current research, based on the field study of an enterprise in C hina, a production planning and control framework for the case company(represented with ‘A' hereafter for the purpose of confidential) is developed by integrating material requirement plan(MRP), JIT and TOC. More specifically the thesis is focused on make-to-order policy in the upstream(welding production line) and make-to-stock policy in the downstream. The research focused to solve the production planning problem of these two sections with an aim to reduce manufacturing cost and increase the capacity utilization and on time delivery of the orders.For the base welding production line, the problem of production and inventory fluctuations is analyzed and the economic lot sizing problem(ELSP) with multi-product batch scheduling technique is studied to minimize the inventory holding cost setup cost. Moreover, the coordinated allocation of production capacity and production sequencing is realized by a proposed ELSP model.In the downstream process(axle machining line), two problems including the long delivery lead-time and low capacity utilization are analyzed. Furthermore, a multi- varieties and small batch scheduling model is developed for the case company. Moreover, batching of the order and production sequencing are combined by proposed multi- varieties and small batch scheduling model, based on the capacitated lot sizing(CLSP) to minimize the manufacturing lead time and order tardiness time.The proposed methods are integrated into a home-made Advanced Planning System(APS) called X-planner and is applied into the case company A to build a collaborative production plan with the downstream process being of make-to-stock and the upstream process of make-to-order. Preliminary demonstration of the implemented in X-planner gives significant results.