Research On Preventive Maintenance Strategies For Bogie Components Of Multiple Unit Trains

As one of the most important components of the high-speed train unit,the bogie is conducive to ensuring the safety and reliability of the train unit’s service through scientific and reasonable maintenance decisions.The maintenance decision includes two aspects:one is to determine the maintenance method of the component,and the other is to determine the maintenance timing of the component.This article focuses on the preventive maintenance strategies of regular maintenance components and condition based maintenance components in bogies.The main research contents are as follows:(1)To determine the maintenance method of bogie components,the evaluation indicators that affect the maintenance method of bogie components are analyzed from the perspectives of maintainability,reliability,and economy,and corresponding scoring standards are formulated.Based on the scoring criteria,each component in the bogie is scored separately.Calculate the membership of each component for post maintenance,periodic maintenance,and condition based maintenance based on the scoring results,and obtain the maintenance methods for each component of the bogie using a two-level fuzzy comprehensive evaluation method.(2)In order to reflect the hierarchical maintenance system of the high-speed train unit,this article constructs a mixed failure rate model of initial,medium,and high levels for components with regular maintenance methods.Calculate the preventive maintenance interval mileage of components based on the minimum reliability and failure rate functions during operation,and provide a method for determining the level of preventive maintenance activities of components using cost-effectiveness ratio.On this basis,a single component preventive maintenance strategy model for three-level imperfect maintenance is constructed,and the total cost of component preventive maintenance and three-level preventive maintenance strategy are obtained by solving the model.(3)In order to reduce the total cost of preventive maintenance for bogie periodic maintenance components within a limited service mileage,considering the economic correlation between each component,and with the goal of minimizing the total cost of preventive maintenance,a multi component preventive opportunity maintenance strategy model based on three-level imperfect maintenance was established.Genetic algorithm was used to solve the model,and the optimal preventive opportunity maintenance strategy for multiple periodic maintenance components was obtained,And compared with the preventive maintenance strategy of a single component,the effectiveness of the preventive opportunity maintenance strategy model was verified.(4)For condition-based maintenance of components,based on the method of dividing degradation intervals,the maintenance activity areas of components are divided according to the size of component degradation.The possible combination of maintenance activities formed by multiple components during maintenance and their probability of occurrence are analyzed,and the opportunity maintenance strategy model with the lowest expected maintenance cost rate for multiple components within a single maintenance cycle is established using the opportunity maintenance theory,Use genetic algorithm to solve the model and obtain the optimal maintenance strategy for conditionally repaired components.The research results of the paper can be used to develop preventive maintenance plans for bogie components,which is beneficial for the maintenance management department of the high-speed train unit to make scientific and reasonable maintenance decisions.It can also provide certain reference value for formulating preventive maintenance strategies for other multi-level imperfect maintenance or condition based maintenance components.