Research On Quality Improvement Of H Company Yoke Sheet Based On Six Sigma

With the continuous development of economy and technology level,the market competition is very intense,and the customer’s expectation of products is also higher and higher.H Company’s yoke stamping is an important component of its main products hydro-generators.In recent years,the phenomenon that the burning angle of hydro-electromagnetic yoke produces bump often exists,which has become a common problem in the industry.At present,due to customer feedback,the size of the bumps of the magnetic yoke punching sheet produced by the company does not conform to the standard.The defective bumps have brought about problems such as rework and manual removing bumps inside the enterprise,which has increased the input of the production cost of the enterprise,at the same time,this situation also seriously affected the hydro-generator production follow-up screw through the smooth process,on the production caused obstacles.Therefore,the bump quality of the yoke stamping products needs to be improved.In this paper,Six Sigma Quality Management is applied to the processing of yoke sheet to improve the quality of the products.According to the current product quality status of the company,the introduction of Six Sigma’s DMAIC improvement methods.Through five stages of process definition,measurement,analysis,improvement and control,the project team is formed and the project schedule is arranged according to the customer’s requirement.Secondly,from the actual production process of the product,the measuring system analysis,evaluation matrix,hypothesis test and other methods are used to find out the significant factors that affect the quality level of the bump point of the yoke.Then the product quality is optimized and monitored through the analysis tools such as experiment design(DOE),statistical process control(SPC).Finally,the improved product quality is verified and economic benefits are analyzed,and control plan and further quality management measures are proposed.In this paper,Minitab software is used to analyze the data,which ensures the scientificity and accuracy of the improvement process and provides powerful technical help for the whole improvement project.Prior to the improvement of the project,the bump size of H Company ’ s yoke stamping products was beyond the standard,and the high defective rate of products was always a problem for the company.By implementing the Six Sigma Management Project and combining the relevant statistical methods,the optimal production process of the product is finally determined,and by response optimization,under the optimal production process conditions,the average size of the minimum bump can reach 0.1132 mm.The improvement project can effectively improve the quality of the bump and meet the requirements of the specification.The improvement of product quality has been fully affirmed by customers,which not only avoids rework,artificial removing bumps and other problems,but also reduces the loss of internal quality and brings greater benefits to the enterprise.The quality improvement methods used in this paper are also applicable to the same kind of production enterprises,and also provide some reference for other related enterprises.