Assessment of Spare Parts for System Components Using a Markov Model

This paper describes a simple and practical reliability model based on a stationary Markov process for assessing the number of spare parts required for a group of bundles of similar component parts. The proposed model accounts for a number of factors that affect the number of spare parts. The factors include the number of bundles, bundle size, bundle failure rate, time required to repair the failed part or to acquire a new spare part, time needed to install the spare part and any redundancy in the bundle. In addition, the proposed model is capable of handling bundles of different sizes. Two performance criteria namely the group availability criterion and the system total minimum cost criterion can be used in the spare part assessment. The purpose of this paper is to present the new reliability model and to compare its results with other existing probability models.