Analysis And Improvement Of Gasoline Engine Injector Leak

In recent ten years along with the incomes of our residents increase year by year,the car is no longer the luxury goods.Quite a lot of people can afford an automobile.Automotive accessory manufacturers grow fast while the automobiles become popular.When these manufacturers share the big cake,they also should make effort to meet the requirements of lower cost,higher efficiency and better quality.In this paper firstly it shows us the production quality status of the core product fuel injector in B company.It uses Pareto chart to find out the major quality problems are leak out of specification and dynamic flow out of specification.Then the measurement system of leak is analyzed and evaluated from the statistical characteristics of repeatability,reproducibility,bias,linearity,stability and discrimination.It is found that the measurement system's repeatability and reproducibility need to be improved.The improved measurement system is analyzed and evaluated again to confirm that it is good.Finally the design of experiments methodology is used in the factorial design of injector leak test.The injector leak is defined as the response while the dimensions of relevant parts are defined as factors.The test data are analyzed by ANOVA in minitab software.After analysis we can find the dimensions which have significant effect on leak and if there is interaction between dimensions.The regression between leak and each dimension can also be found to determine the improvement plan.