The Application Research On The Quality Improvement Of Wheel Speed Sensor

For long years, with the big success what such as Motorola,GE,Allied-Signal get,some international company start to follow and join6Sigma quality management. Moreoversome domestic company also start to learn and implement6Sigma. But until now, there arenot enough people who are really expert in6Sigma management in China, and there is sofew domestic company which can achieve a big success in6Sigma quality management, Sothere is long way to go to extend the6Sigma management to popular.Under background of a big international company, even more under the big challengepressure from market and internal management requirement, Continental AutomotiveChangchun Co., Ltd(CACC) started to implement6Sigma quality management very longago, in order to improve the quality management level for each Business Unit. It is so luckyfor me to join a quality improvement for Wheel speed sensor, as a team member,worktogether to improve the quality of wheel speed sensor production line based on6Sigmamanagement.The main characteristic for6Sigma management are: the top Satisfaction fromcustomer and the Minimum cost for company. To implement6Sigma management intocompany successfully means both customer and company are content with what you didsimultaneously. For customer, it is most acceptable price and got satisfactory product ontime; and for company, it is to get maximum profit with minimum cost and timing. We willintroduce the6Sigma analysis method including basic principle and procedure, we also havespecific and definite explanation for each phase(DMAIC), in order to build a firm theoreticalbasis.It starts from a production quality issue(Wheel speed sensor failure) which we currentlymet in our company: we found a6Sigma quality improvement project team, and the teammember are from each function and position. The project team have several rounds of6Sigma quality improvement workshop meeting to discuss main cause which may effect thiswheel speed sensor production line; The management define project scope, we collect andmeasure on site production line data, evaluate our current process; and we try to find thepossible reason by using Fishbone map which is from man, machine, material, method andenvironment. After analyzing from Causality Matrix, we found the main cause which effect our current wheel speed sensor quality are the shape of winding area, the dip depth ofleadframe and overmolding pressure. After that we define the quality improvement plan andtry to validate these plans by DOE. We tried our best to find the prior plan by Minitabsoftware analysis. When the process capacity was stable (CPK>1.67), We will transfer thisimprovements process to plant,in order to implement the further production byPFMEA,Control Plan, and Work Instruction. We also follow and monitor the processquality by SPC.The team always follow and tracking this6SIGMA quality improvement for thiswheel speed sensor production line. We found that after the quality improvement on thiswheel speed sensor production line, the failure rate by broken wire decrease by as much as50%, the scrape rate also decrease from initial0.26%to current0.1%, our FPY index alsoupgrade. The most of important is that we have less complaint from customer. After all, this6Sigma quality improvement project saved about180000RMB. The company also get a bigprofit by this quality improvement project of wheel speed sensor.When carrying out this6Sigma quality improvement in our company, I found that thecorporation can achieve significant profit when the6Sigma quality management isimplemented very well, The6Sigma management can make corporation continuousimprovement,and all of these can give corporation direct efficiency. On the other hand, thecorporation carry out6Sigma management well means company has excellent idea andculture which the corporation always pursue perfect state,always improve product quality,save cost,increase customer satisfactory. This can make corporation has better future.