Quasi-renewal approach to spares provisioning for deteriorating systems under imperfect maintenance

This paper presents algorithms for deriving optimal spares provisioning under the assumption of imperfect maintenance policies for deteriorating systems. The spares provisioning models are developed to calculate the upper and lower bounds of system availability using a generalized quasi-renewal process. It is assumed that the system will deteriorate gradually with decreasing operation and increasing repair intervals. The optimal spares investment is obtained by using the numerical approach. The annual procurement of spares can be acquired and allocated with the optimal mix and amount to fulfill the operational availability requirements. Numerical examples are presented to illustrate the models results through a set of real field data.