Research On Production Scheduling Integrated With Preventive Maintenance Of Non-identical Parallel Machines

In a production system, it has important influence on improving the economic benefits of enterprises and market competitiveness to establish production scheduling plan and reasonable equipment maintenance plan. On the one hand, production scheduling is the key to ensure the production plan to be completed, and reasonable arrangement can reduce the manufacturing resources waste. On the other hand, equipment maintenance management is critical to ensure that equipment production efficiency and to reduce the manufacturing cost. Due to the fact that equipment maintenance and the production scheduling influence each other and has a coupling relationship. An equipment failure caused by the equipment recession would affect the production scheduling, and production load would also affect the running state and stability of the equipment. Therefore, the integration research of production scheduling and preventive maintenance in the modern manufacturing enterprises, and solving the contradiction between the scheduling and the maintenance, have important significance to optimize the production and maintenance activities roundly, reduce the comprehensive cost, improve the efficiency of the whole production system. This paper researched on production scheduling integrated with preventive maintenance based on non-identical parallel machines, the integrated model was constructed and solved, in order to enhance the manufacturing system stability, to reduce the manufacturing cost, to optimize production, and to improve production efficiency, and finally enhance the enterprise competitive ability. In this paper, the following several aspects are included:Firstly, the overall research on the integration problem of production scheduling and equipment maintenance management of Non-identical Parallel Machines system was put forward. The characteristics of the production scheduling of Non-identical Parallel Machines system were analyzed, and equipment preventive maintenance strategy and theory of reliability were studied. Then, the coupling relationship of production scheduling and equipment maintenance management was analyzed. Based on this, the research train of thought and the corresponding technical route of the integration research of production scheduling and equipment maintenance management of Non-identical Parallel Machines system were put forward, and also the key problems were analyzed.Secondly, the integrated model of production scheduling and equipment maintenance management of Non-identical Parallel Machines system was constructed. Hybrid maintenance strategy was put forward based on preventive maintenance strategy and the theory of equipment reliability. Combining with the scheduling characteristics of the different speed system parallel machine, the coupling relationship of production scheduling and equipment maintenance management was quantified. In turn, the integrated model of minimizing the system completion time and maintenance costs per unit time as the goal was constructed.Then, the solving algorithm of the integrated model was researched. Non dominated sorting genetic algorithm with the elite strategy(NSGA-II)was selected out from several Multi-objective optimization algorithms. Aiming at the shortcomings of the standard NSGA-II, through bringing in non-dominated sorting method of minimum standards, external memory, and improved selection mechanism, etc., an improved multi-objective genetic algorithm was designed.At last, by analyzing the instance of the company I, the correctness and validity of the improved algorithm proposed and the integration model in this paper have been verified.