Study On Quality Improvement Of Bus Welding In Company Y Based On Lean 6σ

In recent years,as the focus of the construction of a modern industrial system,the transformation and high-quality development of China’s real economy,such as manufacturing industry are at a critical moment.With the arrangement of the strategy of quality power and manufacturing power,it brings solid policy guarantee for the transformation and upgrading of domestic manufacturing industry.Meanwhile,with the continuous development of Industrie 4.0 concept and the rise of independent brands,a change of science and technology and industry will profoundly influence the ecological migration of global bus industry,in addition,China’s bus industry is also facing a profound changes and a big adjustment unseen in a century,combined with the influence of international industrial chain and COVID-19,competition among industries has also intensified.As a domestic bus manufacturing enterprise.Y Company has 145 types of bus products with an annual output of 70,000 sets,due to its large number of factories and workshops,the production level and quality management level of the production line are uneven,and the problems of product quality and resource waste still cannot be improved,among which the quality management of bus welding link is particularly prominent.Therefore,in order to improve the production efficiency and product quality of Y Company,and further enhance its industrial competitiveness,it is very feasible and necessary to introduce the theory and methods of Lean Six Sigma into the quality management of passenger car welding.Combined with the principle of theory and practice,with a combination of qualitative and quantitative analysis methods,and through the field investigation,visit,analysis,this paper develops a systematic study on the vehicle welding quality of Y Company.First,it analyzes the value process of bus welding of Y company with lean thought,and by means of Lean Six Sigma statistical analysis methods and tools,through chi-square test,full factorial test design,response surface design,based on the multi-response optimization of satisfaction function,the key influence factor of welding quality was found,and the optimal parameter combination was acquired;And then,through the guiding ideas and methodological tools of lean production,it improves and controls the field process,optimizes the production process combined with the ECRS principle,the balance rate of the production line was also improved;Finally,through the analysis and verification of the improved measures,the disposable qualified rate of welding was effectively controlled,the accuracy of the bus body,the flatness and strength of the thin-gauge skin,and the production efficiency of the vehicle welding were all improved,and the project summary was solidified to the work instruction book.This paper validates the applicability of Lean Six Sigma theory and tool method to bus manufacturing enterprises.Through comprehensive use of various test methods,it provides certain theoretical significance for improving welding quality of galvanized sheet and hybrid gas shielded welding.At the same time,it also provides certain practical significance for other enterprises in bus manufacturing industry in terms of quality management and improvement of welding and fitting.