A Study On Balancing Of Car’s Body-in-white(BIW)Mixed-model Production Line In Body Shop

The growth of economic globalization and increasing of customers’ diversifieddemands motivate manufacturing enterprises to meet the variable demands rapidly withgood flexibility, lowest cost, best quality and shortest delivery time. With less or withoutany substantial modification to existing production facilities, mixed-model productionlines(MMPLs) are capable of producing a set of similar models of a productsimultaneously, providing that MMPLs are well balanced and sequenced. Based on theproduction of Car’s Body in White(BIW) shop in BBA company, the thesis makes thisstudy on the optimization of balancing sequencing problems in MMPLs, using therelated IE tools, Value-added production system(VPS) and mathematical algorithm.At first, the basic theory of the balancing of MMPLs and the current situation of30 U BIW shop and its production lines were introduced; the process flow of BIWproduction lines, mixed model patterns and its arrangement graph of BIW shop werealso analyzed and studied.Then, the Takt unbalanced of Framing 1-GEO and Framing 2-GEO station wasimproved using IE theory, like the bar chart, 5W1 H and ECRS etc.. The VPSoptimization projects of transit unit layout and trailer’s delivery point were alsointroduced. In order to solve the sequencing problem of MMPLs, a mathematical modelwas established with two objectives of keeping average parts consumption rate andminimizing total task overloaded time. To achieve this, a multi-objective optimizationalgorithm with genetic algorithm and particle swarm optimization algorithm(GA-PSO)was designed, and then it was applied in the case study of sequencing problem in MetalFinish line.Finally, Witness software was used respectively to simulate the production processof Framing lines before and after improvement, and the sequencing method in MetalFinish lines, which verified the feasibility and reliability of these methods.All the optimization technologies and methods proposed in this thesis, will notonly play a good theoretical guiding role for the balancing and sequencing of MMPLsfor Car’s BIW, but also provide the reference for the similar study on balancing ofMMPLs in the future.