Reliability Research On Urban Rail Transit Vehicle Door System Key Components

Urban rail transit is the overall and supporting infrastructure of urbanization and urban modernization, and is the backbone of city comprehensive transport. By the end of2013, total36planning urban rail transit lines (about6000kilometers) have been approved. China’s commercial capital has in reach to2266km.How to guarantee operation security of urban rail transit system, enhance the level of operation maintenance, lower the whole life cycle costs, which have already become an important problem of influencing urban healthy development.The fault statistics of the Guangzhou metro in the last years shows that the door system is the one which is occurring fault most frequently in the all sub-systems of the urban train. At the same time, the failure rate of door safety relays is particularly prominent. Therefore, researching on the door system and the door safety relays are of great importance.This article takes the door system and the door safety relays as the research and reliability assessment object and carries out the following research:(1) The reliability modeling of door sub-system is established and fatigue lifetime of the safety relays is analyzed.(2) Using time-tested method to analyze the failure rate trends is more feasible. And then get the failure rate and life distribution which are more conform to reality. Comparing with traditional and improved methods we can see the last one is better. Because the traditional approach may render error risks of neglecting field data are not necessarily mutually.(3) It proposes a life prediction method of cumulative frequency LPMCF (Life Prediction Method based on Cumulative Frequency).It is applied to the prediction of the door system key components life time. Using the time between failures as the research object, one conclusion can be obtained. The conclusion is that using the time quantum which has small cumulative frequency and high failure rate as fault prone time interval.(4) We build a relay reliability life testing platform for further evaluation of relay life. Collection the dynamic resistance characteristic parameters of the relay closed process use100,000times per second data acquisition rate, and comprehensive analysis of data using MATLAB and SQL Server to given the relay life indicators.In this paper, the research provides support for the building of urban rail transit train running safety and integrated maintenance network system. And also provides a reference basis for the realization of the urban rail transit train dispatching command, maintenance, security and emergency management.