Integrated production maintenance model under imperfect age-based maintenance policy and non-negligible maintenance times

This paper deals with an integrated production maintenance model where preventive maintenance (PM) activities are carried out at the end of each production run or at failure, whichever of them occurs first. PM activities take a fixed amount of time. However, due to the random nature of failures, the stock built during the production period may deplete before the next production run starts, leading to some loss in demand. After N production runs, the process is replaced (or undergoes a major repair), which brings it to the "as-good-as-new" condition. A mathematical model is derived for this problem and a model analysis conducted to characterize optimal solutions. Numerical examples are used to illustrate the proposed model and conduct a sensitivity analysis with respect to key model parameters.