Dynamic Optimization Model for Mining Equipment Repair by Using the Spare-Parts Inventory

We present the dynamic control system for the service rate in an M/M/1 queuing system, to optimize the inventory of critical repairable spare components for a fleet of mobile equipment in presence of an adjustable single server repair facility, namely, the repair rate can be expedited or slowed down. We consider the normal and expedited rates, when the faster repair rate implies higher repair costs. The repair rate selection depends on the number of units in operational condition; actual operating units plus stock on hand is generated at the moment of demand for a spare. The resulting optimal policy is to minimize the expected cost per unit time for the inventory system in the long run.