Development Of Accumulator Reliability Test Bench And Reliability Evaluation

The manufacturing industry is the leading industry of the national economy and the foundation of the country,and the hydraulic transmission with unique advantages system is widely used in all fields of the industry.As an important auxiliary element in hydraulic transmission system,the reliability of accumulator is the key to the efficient and stable operation of the whole hydraulic system.In the reliability research of accumulator,the accumulator test bench with excellent performance and the accurate and reliable reliability evaluation method is very important.The project is to design a high efficiency,energy saving and high automation accumulator test bench,and then test and evaluate the accumulator reliability.In view of the traditional accumulator test bed problems,such as serious energy consumption,high single pump driving load and poor test stability,the hydraulic system of accumulator reliability test bench is designed.The energy recovery function is realized by using double accumulator alternately filling and discharging liquid.The method of low pressure large flow pump and high pressure small flow pump reduces the load of single pump and improves the stability of test.Then,the selection of main hydraulic components is completed according to the main technical parameters.In order to solve low automation degree,low test precision and unfriendly manmachine interaction of traditional accumulator test bench,the measure & control system of accumulator reliability test bench is developed.Firstly,the overall scheme of the measure& control system is formulated according to the functional requirements.Then,the software is developed based on the idea of modularization.The upper software selects the LabVIEW as the development environment platform,which designs the user-friendly man-machine interface for each function block,and the lower uses the PLC as the controller to write the concrete program according to the required function.Finally,communicating with the host computer through the OPC protocol.The whole system can realize data acquisition,data processing,real-time curve drawing,saving and other functions.The improved distribution curve method is used to analyze the reliability of Weibull distribution data without failure.This paper compares several methods of failure probability estimation in distribution curve method,selects multi-layer Bayesian method to improve,corrects the prior distribution of failure probability based on Bayesian idea,and modifies the upper bound of failure probability according to the order of failure probability.The improved distribution curve method is obtained.The feasibility of the improved distribution curve method is verified by non-failure simulation data and classical non-failure bearing examples.This paper designs an accumulator test program and obtains no failure data.The shape parameters and scale parameters of the accumulator are obtained by the improved distribution curve method,and the reliability of the accumulator is evaluated,which provides a theoretical basis for the practical application of the project.