Inventory Management of Slow-Moving Materials

Abstract

This chapter addresses inventory management of slow-moving materials and special purpose materials required in the implementation of maintenance projects as well as in other projects where conventional inventory models are not applicable. Materials planning for slow-moving expensive engineering spares is discussed as special spares, adequate warning spares, and inadequate warning spares. In the first two cases, the optimal policy should be not to keep any inventory, but place an order just in time. Reduction in lead time should be a prime objective in reducing inventory of slow-moving but expensive spares. Only for “inadequate” warning spares, we need to keep some inventory. Second important problem in spares inventory control discussed is initial provisioning of rotable spares used in situations employing modular maintenance practice such as for aircraft maintenance. Trade-off between rotable spares inventory and maintenance capacity (maintenance crew size) are also explained. By expediting overhaul cycle time, rotable spares inventory can be reduced.