The Mixture Reliability Model Of Pantograph Mechanical System In A Life Cycle

In the world, High-speed railway has developed rapidly. By building the rapid railway for passengers and transforming the existing railway, the train speed was improved greatly. At the same time the vibration between pantograph and catenary was more serious, and there were carck, fracture, wear and tear in the parts of the pantograph. The serious failure of the parts resulted into the maintenance cost improvement, the reliability decreasment, and train in danger. Therefore the study on reliability of pantograph is necessary. The traditional study method about reliability is based on the assument of the independent parts with only two states. And it isn’t fit with pantographs with multi-state and multi-mode parts. New methods based on multi-state and multi-mode parts were put forward which can design the section, predict the reliability and life, predict the time of maintenance.Funded by the Natural Science Foundation Committee of China (No.51075341), the11th Five-Year Plan of National Science and Technology Support (2009BAG12A01) and the National Basic Research Program of China (2011CB711100),studies in this paper mainly centered on various aspects below..(1) Studies on reliability of mechanical system in the past and now in the world are reviewed. The key problems on the reliability of pantograph was described, and the significance and research focus of pantograph are indecated.(2) A new definition of multi-state and multi-mode system is brought forward, and its drawing method is given; The mixture theory is introduced; The definition and the theory are the base of the reliability analysis of pantographs.(3) A multi-state and multi-mode static stress model is established and the results of the model are the inputtment of another model about prediction the static reliability and section size of the parts of pantograph. These models are used in a high-speed pantograph, and it is available.(4) A multi-state and multi-mode dynamic stress model is established and the results of the model are the inputment of another model about prediction the life reliability in which the relativity of the multiple modes is considered. The results of the sigle mode model and the multiple mode model are compared and the second result is more reseanable.(5) The multi-state and multi-mode reliability prediction models about series structure, parallel structure and reserve structure are put forward. In these models the relativity of the parts is considered and an example improves the reasonable of these models. And the better reserve structure is gotten.(6) The life distributions of the multi-state and multi-mode parts are gotten based on the datas in the running train; A new states tree is put forward to analyze the reason of failure and the hazard of the state; The multi-state and multi-mode replacement policy and detection strategy are established to determine the replacement time and detection time.