A Heuristic Replacement Scheduling Approach for Multi-Unit Systems With Economic Dependency

For a multi-unit system with economic dependency, it is difficult to develop an effective joint replacement schedule due to the stochastic complexity of the system failure-repair process. As a result, restrictions have often been introduced in the maintenance policy specification and decision problem formulation. In some cases, these restrictions have resulted in a reduction in the optimality or effectiveness of the proposed schedule. In this paper, we propose a general opportunistic maintenance policy for multi-unit systems with economic dependency. Two cost boundary conditions are developed in order to evaluate the potential cost savings achieved by implementing the opportunistic maintenance policy. A heuristic approach based on the application of the single-unit model is presented for developing the opportunistic maintenance schedule via an example problem. The effectiveness of the resulting schedule is demonstrated through simulation experiments.