The analysis of spares support policy with repairable item under the consideration of discarding

The problem of how to formulate support policy with spares under the consideration of discarding is researched. In order to solve this problem, Firstly, the mathematical model is constructed, which obtains the relationship of failing number of repairable items before it discarded and the repair-discarding rate. Secondly, the repair item extreme value of failures under the consideration of discarding rate is derived, as well as the distribution function. Then, basing on the analyzing mentioned above, the method of how to calculate the number of spares on hand is given. Each effect of parameter on the inventory on hand along with time is analyzed and, further, the inherent law of inventory changing rule is derived. Finally, experiments show that the model works well and the result establishes good foundation for further research in relative areas.