Production loss based maintenance with uncertain failure service times

Maintenance management often focuses on the minimization of the repair cost and the part replacement cost. In this paper a production cost based maintenance scheme is proposed to minimize the production loss due to unscheduled equipment downtime events. Two maintenance plans, standby redundancy and vendor repair, are discussed and their impacts on the downtime cost are analyzed. The idea is to reduce the system mean time to repair so that the system availability can be kept at a high level leading toward the minimization of the potential production loss. Our method will be applied to the maintenance planning for automatic test equipment, a capital-intensive system, in semiconductor manufacturing industry.