Location optimization for spare parts depots based on (r, Q) inventory policy

Supply of spare parts directly affects the support level of equipment system. However, a large number of spare parts depots often disperse with each other. In this case, the support cost is high and system efficiency is low. With the development of transport capacity, centralized allocation of spare parts can improve system efficiency and reduce support cost. Thus, a reasonable choose of depot positions to ensure a more timely supply becomes desperately needed. Besides, optimal inventory allocation for spare parts has great effect on support efficiency. Inventory holding cost is an important part of total cost. This paper will make optimal study on depot location based on the (r, Q) inventory policy. First, inventory cost of (r, Q) inventory policy is analyzed, and then combined with construction and transportation costs to be the total cost. Next, some effectiveness parameters of equipment support are considered. Availability, fill rate and the excepted down time are selected as indicators to evaluate positions of open depots. Finally, with effectiveness parameters being integrated into the location process, a depot location model considering inventory policy is established. At the end of this paper, a numerical example is designed and genetic algorithm is used to prove the validity and feasibility.