Abstract: The dominant multi-echelon inventory models for repairable spare parts are based on (S-1, S) inventory policy, which means that the failed item is sent back to a depot immediately and a spare part application is issued to the depot at the same time once an item fails at a base. The army has a lot of items to manage, however, frequent application and transportation will bring considerable fare and work-load. In order to address this problem, a two-echelon inventory allocation model is established based on (T, S) inventory policy. The support process of repairable spare parts based on (T, S) inventory policy is illustrated, in which both the returning of failed items and the application of spare parts are completed in a period instead of immediate. The evaluation indexes of spares support effectiveness are presented with the consideration of obsolescence rate and application delay, aiming to minimize the support expense while satisfying the equipment availability constraint. An adapted marginal analysis is then proposed to find the best answer of the model. Finally, an example is shown to prove the effectiveness of the proposed model, and (T, S) and (S-1, S) are compared. The result shows that, compared to (S-1, S), (T, S) is more suitable for spare parts with relative high failure-rate and low price.Key

Key words: repairablesparepart, two-echeloninventoryallocation, periodicinventory, marginalanalysis