Research On Quality Analysis,Improvement And Control Of BIW In Company B

With the gradual transformation of the traditional manufacturing industry into an intelligent factory,the quality problems in the production process had changed from single and simple to multiple and complex.In recent years,problems such as increased supply chain costs,shortage of parts,stoppage and production stoppage caused by the epidemic also brought great challenges to the manufacturing industry.This paper introduces six sigma management method,takes the BIW workshop of B company as the research object,based on the analysis of production data such as process flow,and from the perspective of actual site,completes the improvement project of reducing the defect rate of BIW.This study is divided into two stages.First of all,on the basis of summarizing the complex and diversified quality defects existing in B Company,the six sigma management method is introduced,and the DMAIC process is used as the framework to analyze the production process and quality status of B Company by using customer demand analysis CTQ and Pareto rule.The body in white defect is determined as the main research object of this paper,and the main factors that cause the high defect rate of body in white are analyzed emphatically,which determines the research direction for subsequent improvement.Then,the reliability of the measurement system and production data is determined through the analysis of the measurement system and the process capability of the current production line.Then,by brainstorming,cause and effect diagram,C&E matrix,hypothesis testing and verification and other methods,the key influencing factors of BIW quality were listed and screened,and the production process flow of non quantitative key influencing factors was improved.Through the improvement in the first stage,the defect rate of BIW has not reached the preset target.In the second stage of improvement research,DOE full factor experimental design is used to optimize the welding parameters of laser welding.First,the model is preset according to the three welding parameters of laser welding: "welding power","wire feeding speed" and "welding speed".Then,the preset model is stepwise regressed through the replacement factor interaction polynomial,so that the model can fully describe the relationship between the three welding parameters and the welding quality.Then,use Minitab software to carry out residual analysis on the current model,identify the significant factors and fit the regression equation model.Then the optimal solution of welding process parameters is obtained by screening the optimal response,and its effectiveness is verified in actual production.Finally,IM-R control chart and other management tools are used to verify and control the improvement results,and the effectiveness of this improvement is proved by comparing the production process capacity before and after the improvement and analyzing the economic benefits.In this paper,through the six sigma improvement research on the quality defects of BIW of Company B,the defect rate of BIW is reduced,the production line beat and production capacity are improved,and the annual production cost can be saved about 540000 yuan.This study proves the feasibility of implementing Six Sigma management in Company B,and also provides reference for subsequent improvement projects of other production lines.