Optimal maintenance schedule decisions for machine tools considering the user's cost structure

This paper proposes a model for obtaining optimal preventive repair and replacement intervals of a machine tool subassembly considering the user's cost structure and the effect of major overhauls. Corrective actions are considered as minimal, whereas preventive repair and major overhauls are considered as imperfect in this paper. The objective is to obtain optimal repair/replacement decisions for the machine tool subassembly such that the expected life-cycle cost contribution over the whole life of the system is minimised. The proposed strategy improves over other existing strategies since it simultaneously considers the effects of the user's cost structure and major overhauls, while optimising the preventive repair and replacement intervals. A numerical illustration is provided to demonstrate the general application of the proposed approach.