Maintenance Strategy Optimization And Decision Model Of The Urban Railway Car Equipment

For a long time, the equipment maintenance modes of urban railway car equipment in our country adopted periodic maintenance which is based on wear theory. The single periodic maintenance mode can't meet the need of increasingly complicated and delicate and more and more electronic devices of the urban railway car equipment. It always leads to the result that insufficient or oversupply maintenance which may cause decrease in equipment reliability, which against the goal of maintenance. In view of the shortcomings of insufficient or oversupply maintenance of single mode in periodic maintenance which made a low cost performance, this paper will find a more suitable maintenance strategy to urban railway car equipment.This paper mainly engaged in the following aspects of study:(1) This paper firstly analyzes the optimization factors of maintenance strategy, then discusses inherent property characteristics of the urban railway car equipment and the failure rate curve of urban railway car equipment, discusses the function and role of urban railway car equipment and classified urban railway car equipment, studies the FMECA of urban railway car equipment and application scope of each maintenance strategy. Then the optimization of maintenance strategy is realized base on safety and cost.(2) Abstract decision of different objects of maintenance mode, such as economical or possibility or efficiency. Analytic Hierarchy Process analysis method combined with fuzzy comprehensive evaluation method was used in this paper to decide Maintenance mode.(3) In the view that deterioration of equipment can be the base to determine the maintenance level, this paper proposed maintenance state transition probability matrix, used Markov theory to build the model that can make decision of maintenance level.(4) In order to provide emergency maintenance resources timely and accurate, the paper proposes the optimization of position selection of emergency maintenance supplies warehouse location in two phases. The purpose of first phase is building the time-operate cost model and using an enumeration method to calculate a number of the optimal solution as pre-value. In the second phase, using the maximum coverage model for the second position selection based on the result of pre-values.(5) Taking urban rail transit vehicles bogie as an example, the bogie was divided into various equipment elements, classified discussion fault characteristics of the equipments and possible maintenance strategy, according to the model built in this paper which combined Hierarchy Process analysis method with fuzzy comprehensive evaluation method to decide the optimum way to repair the bearing of running gear. The paper use Markov chain model to calculate the maintain level and the maintenance cycle of bogie frame. The results have reference and engineering meaning to actual urban rail transit vehicle bogies equipment maintenance.