Research On The Opportunistic Maintenance Strategy Of Multi-units Serial-parallel System

In order to improve the economic efficiency of the modern manufacturing enterprises, the maintenance costs of enterprise production system must be effectively controlled. With the growing complexity characteristics of system structure, the connections of equipments are more and more closely and the failure law tends to be diversified. How to establish a practical maintenance strategy to reduce maintenance costs and loss has become the key problem to be considered in the management of enterprises. This paper is aimed at multi-units serial-parallel systems.According to the different decision bases of system, opportunistic maintenance models based on reliability and loss expectation are established successively. Considering economic correlations and structure correlations and taking minimization of maintenance cost rate as target, opportunistic maintenance models are constructed in finite time horizon.Firstly, the background and significance of the research was introduced, and reviewed researches of domestic and foreign scholars. On this basis, the related concepts of maintenance management theory, reliability and opportunistic maintenance are introduced in detail. The related mathematical bases of modeling are also introduced.Secondly, the age improvement factor and the failure rate deterioration factor are combing to describe the equipment failure rate evolution rule.Taking single equipment as the research object, the preventive maintenance models based on reliability and loss expectation are established respectively and the optimal preventive maintenance strategy for single equipment under different decision bases is obtained.Then, on the basis of single equipment modeling, the research object is extended to the multi-units serial-parallel system.The opportunistic maintenance policy is proposed and the preventive maintenance model based on reliability and loss expecation are established respectively considering economic correlation and structure correlation.The structure influence matrix is introduced to describe the structure correlation of equipment, and the Genetic Algorithm is used to analyze the model.Finally, taking the production line of M company as the empirical research object, the model is verified by analysis of historical data.And analyze the key factors influencing the maintenance decision, provide supports for application of the model.