Quality Improvement Of S Company Automobile Engine Oil Leakage Based On Six Sigma

With the upgrading of consumption,people have higher requirements for the quality of automobile products and pay more attention to the quality of automobile products.With the rise of car sales,also brought an increase in complaints about product quality problems.In order to solve quality problems,improve product quality and achieve long-term development of enterprises,many domestic and foreign automotive enterprises have introduced six Sigma management method.The six Sigma management method has been applied and verified in many fields,especially in the manufacturing industry,which is the most advanced quality management method at present.As a domestic automobile manufacturer,S company has always focused on ensuring the quality of automobile products.In 2021,S Company successively received after-sales oil leakage problems of certain new cars.In order to solve this problem,S Company adopts six Sigma management method to study and improve it.According to the main structure of automobile assembly,automobile maintenance faults are mainly divided into four categories: engine,chassis,electrical appliances and body.The main components of the engine are cylinder block,cylinder head and crankshaft.In order to ensure the sealing of the engine,the sealing parts in each part are also important.After a series of inspections on product oil leakage,S Company found that the main cause of oil leakage was poor sealing of engine cylinder block.In order to reduce engine oil leakage after sales,the engine cylinder block was selected as the research object,and based on the six Sigma DMAIC model improvement process,a systematic concept and method was established for the improvement process of engine sealing parts oil block quality.First of all,through the defining stage,the rough scope affecting the plugging leakage is preliminarily delineated,and the project team is established.Then,in the determination of phase oil production process comprehensive combing,collect related data to determine the effect of oil leakage of relevant indicators,based on the causal matrix,FMEA analysis methods,such as marking out seven factors,and the oil plug thread sizes,gasket joint,tighten gun installation position and oil plug quickly improve surface quality of the four factors;Then,in the analysis and improvement stage,the unqualified indicators appeared in the data collection and the remaining three key factors of roughness,tightening torque and tightening speed were further analyzed and improved.Finally,the optimal setting state was determined as the installation roughness was 0.8,the lower limit of tightening torque was 38 n.m,and the tightening speed was 20r/min.Finally,the tracking test of the improvement process shows that the average static torque level of oil plug is improved,which meets the standard requirements,and effectively improves the sealing performance of engine cylinder block and product quality.This case project has brought benefits to S Company,and standardized documents have been formed through the implementation of the project results,providing reference value for the company to improve the oil leakage problem in the engine assembly process in the future,and at the same time,providing certain reference value for other enterprises to solve engine oil leakage.