对预防性维修的单部件离散可修系统,假定系统寿命、修复性维修和预防性维修的修复时间均遵从离散的一般分布,修复为完全修复,利用概率分析的方法详细讨论了系统正常、修复性维修和预防性维修3个状态之间的转移关系,在此基础上建立了该系统的瞬态可用度模型,最后进行了仿真校验。结果表明,预防性维修对系统瞬时可用度的影响较大,特别是当系统故障率为单调递增时,合理的预防性维修将起到提高系统可用度的效果,该模型能较好地反映工程中的情况,具有良好的工程应用前景,可以帮助维修人员更好地完成工程系统的保障和维修。
This article studies the one-unit discrete time repairable system with preventive maintenance.The unit life,preventive maintenance time,and corrective maintenance time are all assumed to be non-negative random variables with general distribution,and the maintenance is assumed to be perfect.The transition of the system states is analyzed,including the operational state,corrective repair state,and preventive maintenance state.Then the instantaneous availability model of the system is built,and several textbook examples are given to illustrate the proposed model.The results of the examples show that preventive maintenance can play an important role in improving the instantaneous availability of a one-unit discrete time repairable system.In particular,preventive maintenance can improve the instantaneous availability of a system with increasing failure rate.Engineers can use the proposed model to search for better ways to understand their systems and logistic maintenance,and this model may find plentiful application in engineering practice.