This study concerned models that determine optimal preventive maintenance period to minimize maintenance cost. To determine the preventive maintenance period, we proposed two maintenance cost models for military vehicles. These vehicles' operational characteristics are that preventive maintenance action is not performed after predetermined specific period.
We assume that each preventive maintenance actions reduce the system age by fixed amount or hazard rate by fixed fraction; preventive maintenance is performed regularly; all system failures are minimally repaired; minimal repair and preventive maintenance take negligible time.
MK_X vehicle's hazard rate function, repair cost ratio, improvement factor and predetermined specific period were applied to two models proposed in this paper.
The results show that proposed optimal preventive maintenance period in this paper is better than preventive maintenance period being used currently in terms of saving maintenance cost.
We compared these results with those from Chun's model. And the result of proposed model in this paper is more efficient than the result of Chun's model in terms of saving maintenance cost.
We proposed two maintenance cost models and optimal preventive maintenance period to minimize maintenance cost. These results can be applied to MK _X vehicle immediately and it can reduce the maintenance cost. Two models proposed in this paper can be applied to all military vehicles having similar operational characteristics.
