Simulation Modeling And Evaluation Of Assembly Line Based On The Hybrid Pull Model Of CONWIP

In the early1990s, based on the Kanban pull system of Toyota research, Spearman and his colleagues proposed Constant Work-In-Process (CONWIP) concept of the hybrid pull systems that combined pull with push way.Through mainly controlling the limit work in process (WIP) of production system, the hybrid pull systems can achieve optimum output performance. The paper studies the related issues of the mixed assembly line of flow shop style to build CONWIP pull system. It also extends the hybrid production pull system of CONWIP application in a complex environment, and provides a new pull control method for the assembly enterprise to promote production efficiency.Based on the study of CONWIP theory, this essay analysed the hybrid control features of CONWIP pull model in detail, and proposed a CONWIP pull control method for mixed assembly line.The method sloved WIP limit setting problem, scheduling problem and branching structure of the assembly line with loop control problem in the mixed CONWIP pull system. Based on the concept of pipe flow, this paper proposed a method with system simulation to get WIP limit in the branching assembly line, and designed a search algorithm to adjust the value of WIP. CONWIP scheduling was optimised by genetic algorithm toolkit. Through simulation modeling tools analysis, this essay proposed an optimum solution to control branch of the loop for CONWIP. At last, applying the mixed CONWIP control method to corporation’s a phone assembly line, this paper discussed the different performance betweem Push and CONWIP control methods in the mixed assembly line.Studying and simulation results show that the mixed CONWIP control method is feasible and efficient to response to fluctuations in deterministic or at random, and can better achieve JIT production.