A Reliability-Based Sequential Preventive Maintenance Model

Conventional preventive maintenance(PM) often holds a same time interval T and the age-T policy gives unavoidably decreasing reliabilities at the PM actions for the degradation system with imperfect maintenance effect.This study developed a reliability-centered sequential preventive maintenance model for a system subject to the degradation due to imperfect maintenance,which is more practical in engineering.It is assumed that whenever the system reliability reaches the threshold R,an imperfect PM action should be performed on the system.In order to predict the evolution of the system reliability in different maintenance cycle,a hybrid hazard rate recursion method was proposed based on the concept of age reduction factor and hazard rate increase factor.The optimal PM schedule was deduced by minimizing the maintenance cost rate in the life cycle of the system.The optimization process is based on the Monte Carlo simulation.The simulation results show that this maintenance model is practical and it can provide decision support for maintenance scheduling.