Research And Application On The Scheduling System For The Punching Production Of The Auto Industry

The workload percentage of punching process is pretty large in the four major automotive production processes. The punching process integrates the characteristics of discrete manufacturing and flow line. And its dynamic scheduling is difficult because of the batch exchange, batch sequencing, the variety and complexity of multi-line production. As a result, some bad phenomena were induced such as high WIP level, long cycle time, and coexistence of excessive production and shortage. According to the above scheduling situation of the punching shop, following researches were studied.This thesis deeply analyzed planning modes and their key parameters of make-to-order, make-to-stoke and mixed model in automotive processes. Mixed production mode and its scheduling rules in punching shop, planning and controlling method were also discussed. Meanwhile the heuristic method and intelligent scheduling method such as GA (Genetic Algorithm) were profoundly studied. And the key point of automotive punching scheduling was pointed out: determine the production planning mode of the punching shop first, and then solve the optimization of single line scheduling, and balance the tasks on correlation processes in the end.On the basis of above analyses and researches, the multilayer relating planning model was presented among four major processes of punching, welding, coating and assembling. According to the production characteristic of automotive punching process, heuristic algorithm of rectangle packing was used to solve single line scheduling problem, and GA was adopted to solve multi-line balance scheduling problem for relating processes.At last, a prototype system was implemented for multilayer relating planning and punching shop scheduling. And it has been applied and realized in the JAC-MES system for assemble shop production management in JIANGHUAI AUTOMOBILE and it has a good result and effect.