Automotive Reliability Growth Applied Research And Analysis System Development

The car’s law of three guarantees has made a higher quality requirement for the enterprises, they must constantly improve the reliability of the product to adapt the demand of the consumers well as the laws and regulations.The paper did a research on the diesel engine reliability growth application and established a set of assessment and improvement system of the product quality and reliability. Aimed to improving the quality of the diesel engine and its related products, ensure the after-sales service of the enterprises and provide data and system support for the recall and 3 guarantees of the car,The reliability test was taken by the method of field test. According to the test objectives and requirement we made the test which is scientific and operable. And we made detailed provisions such as how to specific develop the principle of sampling and test conditions and so on. Based on the reliability test, the data acquisition scheme of the test was made including the investigation and field sites etc. A standard data record form which was used to register the fault data acquired by the data collection was designed, which can be used as a criterion by read the fault location, pattern and reason. A standard database of the parts tree, fault mode and fault cause was established. The pre-maintenance data of the enterprise can also be a source of reliability data, and be standardization by the criterion. The reliability database was created with the physical database of the SQL Server 2005 based on the test and function requirements of the test, which was constructed by the following four parts: basic information, product information, fault information and fault analysis. The database management platform with B/S structure was designed to realize the user-oriented operating mode, data management and collection and the research of the reliability growth.Through the functional analysis of the FMECA of the engine and parts, the purpose and expected results of the reliability analysis were given and a plan of the research on reliability growth was made. The function design of the reliability growth research was done. The FMECA related function modules were designed including machine and component fault analysis also with the output report. Each function module’s data processing and interface design were developed by C# language. Through the FMECA analysis of the whole machine and key parts based on the application system of the reliability growth, the following results were gotten:the weak parts which affect the reliability, the proportion of the I-TV fault. Harm degree analysis of the failure mode was carried out, by calculating and ranking the damage of various failure modes find out which mode was the biggest harm degree. Finally find out the oil spill and function failure were the highest harm degree to fuel injection pump, also come out with the harm degrees of the various parts of the whole machine among which the fuel injection pump (high pressure oil pump), starter and supercharging device on the top, which can help find out how to improve the machine quality. By evaluating the overall quality and reliability of the diesel engine, a qualitative evaluation standard of the engine was given based on the fault analysis, which were mainly compound with I-IV fault proportion and distribution of the fault location, patterns and causes. The specific measures and suggestions were given to improve the quality of the diesel engine and raise the whole engine reliability.The failure distribution model and its parameter estimation method of the automobile products have been studied. A set criterion of three valuation parameters optimality has been set, and the methods of comparing different parameter estimation methods. Through preliminary observations failure data of the fuel pump, weibull model was chosen to simulation the failure distribution of the fuel injection pump. Fuel injection pump failure distribution model was established with uniform linear method doing parameter estimation, also using matlab doing the curve fit. By comparing the different small sample simulation estimation method of the failure distribution and find out the best method, the exhaust pipe life distribution model was established. Based on the component failure analysis and determine the distribution of spare parts to forecast its demand, established component fault prediction models, providing technical support for the distribution.