Research On Wear Accelerated Life Test And Reliability Assessment For The Launching Valve Of The Device

If there is a failure occurs in a component during the use of the launching device, which would result in the failure of the entire launching device, and even has a serious threaten to the operators’ safety. The launching valve is one of the most important components of the launching device, and its reliability will affect the normal operation of the launching device directly, thereby affecting the using security of the entire weapons or equipments. Therefore, the study on the reliability of the launching valve has important practical significance.Due to the expensive manufacturing cost of the launching device, a large number of tests are impracticable. By using the limited sample size and limited experimental data, the main purpose of the analysis and research on the reliability of the launching valve is to get the reliability assessment for the launching valve and then forecasting its service life, providing a reference for the using staff to replace the related components timely and reducing accidents.The main contents of this paper include the following aspects:(1) The analysis for the success-failure type test data of the launching valve in the launching device. By starting research with the reliability assessment principles and steps, and using the Bayesian methods, this chapter mainly researched the analysis method of the success-failure type test data from two cases, which are the failure data case and the zero failure data case, and then a numerical example has been analyzed and compared. Finally, the reliability assessment method for the success-failure type series system by using the unit-level data has been researched briefly.(2) Based on the classic wear models and the wear principles, this chapter not only researched the wear mechanism and the main failure wear models between the valve sleeve and the valve rotor of the launching valve, but also researched the most suitable experience wear model to describe the relationship between the wear loss and the working time.(3) According to the wear mechanism of launching valve and the relevant background knowledge of the accelerated life test methods, the acceleration factor, the acceleration stress level and the most suitable acceleration method, which are all in the wear accelerated life test for the launching valve, had been determined. At the same time, the wear accelerated life testing project for the launching valve has been decided and then the test has been carried out.(4) According to the collected wear accelerated life test data, and assuming that the wear life distribution follows the two-parameter Weibull distribution, this chapter gives the reliability assessment of the launching valve. Because of the collected data are all zero failure data, to deal this situation, the failure time extrapolation method and the zero failure data processing method have been used. These two methods give the estimation of the service life and reliability assessment for the launching valve. Finally, the calculation results are analyzed, and the differences between the two methods are compared.