Optimization For The Mixed-model Assembly Lines Of Forklift Based On Lean Production

Many varieties of small batch Mixed-mode assembly line has been intensively applied, but its production efficiency is low in most enterprise for the reason of short of system research in this area.So it is important and necessary to build a reasonable optimization model for Mixed-mode assembly line.On the basis of theoretical research on the optimization of mixed flow assembly line d, this paper analyzes the characteristic and shortages of the present study and proposes a hybrid optimization system which combines the lean production theory and modern optimization methods. Through the lean value stream, this paper identifies two major problems of Mixed-mode assembly line and proposes the way to solve this problems. the optimal model of Mixed-mode assembly line balancing problem and materiel delivery problem is build and solved with modern optimization methods.For the Mixed-model assembly line balancing problem, this paper synthesizes product operating time and assembly technology and regards production pace minimization and weighted average load equilibrium of each workstation to build up an optimization model based on working space and assembly tool constraint. In addition, the genetic algorithm is used to solve this model and the crossover and mutation are improved. At last the optimal solution for Balancing Problem of Mixed Model Assembly Line is provided by MATLAB software.For the material distribution in mix-model assembly lines, this paper design the different material distribution strategyAccording to the characteristics of parts. using synchronous supply strategy for the key parts and making the distribution schedule and operational procedures. For the special parts, using the SPS strategy and optimizing the operational procedures and number of vehicles Empty pullstrategy is used in the general part, the influence of the material delivery, empty pick-up and the rate of material of different stations are analyzed, an empty pull material delivery model is built by taking the shortest travel distance of vehicles and balancing the distribute frequency of the same route as the optimization objective. The empty pull material delivery model is solved by the genetic algorithm.Through synthesizing the merits of the lean production theory and modern optimization methods, this paper builda hybrid optimization system for the Mixed-model assembly line and apply this system in the forklift manufacturing company. the Mixed-mode assembly line balancing problem and materiel delivery problem in the company is analyzed and optimized, providing thetheoretical and practical references for the multi-varieties and small-batch company to riseproduction efficiency.