Research On The Application Of Six Sigma In The Optimization And Improvement Of Product Quality Characteristics

In the competitive market environment,the profit margins of traditional manufacturing are gradually decreasing,and the product quality issue have become increasingly prominent.How to improve and optimize the design of product,reduce the number of repeated design,and introduce effective quality management mode to improve product quality,it's an important issue for enterprises.In the "14th Five-Year" Development Plan for National Bearing Industry,it is shown that one of the reasons for the slow growth of China's bearing industry is insufficient quality brand construction.Because many factors are involved in the manufacturing process of hub bearing,such as cooling method,reserved quantity,spindle speed,etc.,these factors will affect the quality of hub bearing products.At present,these factors are mainly controlled by experience and error method,and lack of experimental design in manufacturing process.To solve the problem of low qualification rate of hub bearings,the key lies in optimizing and improving the existing production process,reducing the impact of key factors on the qualification rate of products,thereby improving the quality of hub bearings.This paper takes racing wheel bearing as an example,based on DMAIC process of Six Sigma Management,integrates orthogonal design,parameter design and response surface optimization method to research the quality improvement of wheel bearing,and provides a set of effective quality improvement mode for enterprises.In the definition phase,the process parameters of hub bearing are taken as the research scope,and it is concluded that the hub bearing position size is the key quality characteristic and the desired characteristic by analyzing the Pareto Diagram;In the measurement phase,the analysis results of Gage R&R are used as the basis to evaluate the effectiveness of the measurement system.Carry out measurement system analysis and process capability analysis on the collected measurement data of racing wheel hub bearing,and establish the hub bearing measurement system;In the analysis phase,the orthogonal table is used to plan the experimental settings,and the signal-to-noise ratio of response value is designed and analyzed to obtain the three factors of spindle speed,feed rate and head pressure as the significant factors;In the improvement phase,the process parameters are reconfigured horizontally,and the second-order optimization model between the hub bearing location size and three significant factors is constructed by using the response surface method.After the optimization model passed the test,the optimal process parameters were obtained as follows:spindle speed of 2892.27 rpm,feed rate of 0.1mm/rpm,chuck pressure of 17.59kg/cm2;In the control phase,the feasibility of the optimal process parameters is verified by comparing the process capability before and after optimization.The improved sigma level is increased from the original to the current level,which shows that the qualified rate of hub bearing is significantly improved under the process parameter level.According to the Six Sigma quality improvement model in this paper,the key quality characteristics and significant influence factors of hub bearing can be effectively extracted,and the relationship between quality characteristics and influence factors can be established,and the optimal parameters can be solved,so as to effectively improve the quality level of hub bearing.