THE IMPACT OF PREVENTIVE MAINTENANCE ON SYSTEM COST AND BUFFER SIZE

In this paper we consider a system with two production operations (typ ically machines) and a buffer between them. Our objective is to determ ine the optimal buffer inventory level, b, that triggers preventive m aintenance on the first production operation. We assume that periodic preventive maintenance will, in the long run, decrease the first produ ction operation's failure rate. A cost model for the system is specifi ed that includes the costs of preventive maintenance and unscheduled r epairs, starving the second production operation, and inventory. The c ost model is dependent on the values of performance measures that are a function of b, which defines the preventive maintenance policy. We model the stochastic buffer content process of this system and obtain the performance measures with an embedded absorbing Markov chain analy sis, Under certain scenarios, the implementation of the preventive mai ntenance program is shown to decrease the system cost and the output p rocess variation. Furthermore, our model can be used to indicate overs ized buffers in such an environment.