Research Based On Six Sigma DMAIC Method In V Company ECU Product Quality Improvement

In recent years,the market competition between fuel vehicles and new energy vehicles is fierce,the market share of fuel vehicles is shrinking year by year,and the sub component suppliers of fuel vehicles are facing the same fate.Customers’ requirements for quality are more stringent,and good product quality will bring more benefits to the company.The VD46 engine control unit produced by V company,in less than half a year since the new project was put on the market in mass production,had water leakage in the pre-assembly high-pressure water spraying experiment of the customer,which was complained by the customer.At the same time,the First Pass Yield rate of the internal production line of the product was only 91.3%,which could not meet the company’s requirements,so the sealing quality of the product needed to be improved.In this paper,Six Sigma quality management method is applied to VD46 ECU production line process to improve product quality.According to the current production line process of the product,the ECU production process is analyzed one by one in strict accordance with the five steps of DMAIC,using measurement system analysis,process capability analysis and brainstorming method,Fish Bone diagram,SIPOC method,C & E matrix analysis and other methods are used to study and discuss,find out the key factors affecting the First Pass Yield rate of products,and then collect data,using the double sample T and paired T and do in Hypothesis test Experiments and other analysis tools analyze the root causes of quality problems from shallow to deep layer.Finally,according to the Minitab response optimizer tool,find out the best parameters for comparison,take corresponding measures for each factor,improve the key parameters of production process,improve the size of jigs and other problems,and increase the First Pass Rate of VD46 production line from 91.3% to 95.6%,reducing the repair rate and scrap rate in the production process is a significant improvement in the production efficiency of the enterprise.Through the Green Belt project,the product quality of company V has been greatly improved,and the ex factory products have been affirmed by customers,which has won the reputation and more opportunities for the company.At the same time,company V has also set an example in the company,introducing the concept of Six Sigma into various projects in the workshop,bringing more profits for the company.