Reliability Analysis And Life Evaluation Of Mechanical And Electrical Systems

Numerical control machine tool is a kind of typical mechanical and electrical system, it has become the basic equipment of the equipment manufacturing industry and the national economy construction, and its reliability technology has become the key common technology which restricts the development of the industry. As a result of the past, there is no accurate data information as a basis for evaluation, therefore,the need to obtain data through experiments. Therefore, the research on the reliability analysis and life evaluation technology of complex electromechanical system for numerical control machine tool has important theoretical and practical significance for the rapid and accurate determination of the weak link in the reliability of numerical control machine tools, evaluating its reliability level and choosing reasonable measures.On the basis of the characteristics of CNC machine tools, the fault tree model is built on the basis of the analysis of the fault tree, the fault tree analysis(FTA), the system is analyzed, and the system is analyzed. The system is characterized by the fault tree analysis. The system is characterized by the fault tree analysis. The system is analyzed. The system is analyzed. In the tree analysis, a model of fuzzy fault tree analysis based on the importance of the model is proposed. Through the typical failure modes of a DC power supply system for numerical control lathe electronic equipment,fault reasons and the effects of in.depth analysis, study the reliability evaluation of NC lathe miscellaneous system in the absence of sufficient reliability data fusion expert knowledge, experience and related factors; finally, according to the numerical control machine tool obey Weibull distribution characteristics, by supporting device for a machine tool factory of a certain type of machine screw nuts of accelerated degradation data are analyzed. Using Weibull model of life distribution model, will the performance degradation data extrapolated to obtain pseudo life data, using screw nut supporting device failure mechanism for the acceleration factor, the pseudo lifetime data conversion for the equivalent lifetime data. Based on the Minitab software to analyze the equivalent life data, verify the life distribution of the lead screw nut. According to the prior information of NC machine tool failure rate, Bayes theory is used to study the reliability test, Bayesian method is used to calculate the life distribution function of the shape parameter and scale parameter ETA estimates, that the types of machine screw nut supporting device failure probability function f(T)and MTTF(mean time between failure(MTBF). Finally, the reliability of screw nutsupporting device are evaluated.In this paper, the reliability analysis and quantitative evaluation method of the whole system, subsystem components and key components are studied. The results can provide a certain value for the reliability evaluation of NC machine tools. Because of the complex mechanical and electrical system reliability theory field involves many contents, difficulty, and some problems need to be further studied in the future.