Spares management for improved maintenance

A recent survey by the US Nuclear Regulatory Commission (NRC) of maintenance practices at US nuclear power plants confirms that spare parts availability is, to some extent, a problem at all but a few plants, and that 57% of the plants sometimes operated in a limiting condition for operation over the last year due to unavailability of spare parts. That's the bad news. The good news is that significant improvement is possible without ballooning inventory. The vast majority of total dollar value of spare parts inventory at power generation stations, whether nuclear or fossil, is rarely used (parts or components that are used 12 or less times per year including many with a history of no use for many years). Inventory Solutions of Akron, Ohio, has developed such a tool, called rarely used inventory stocking logic (RUSL) which is a user-friendly decision support tool for setting spare parts reorder points. Based on statistical computations enhanced to include the most advanced techniques developed for use in aerospace and military combat readiness, RUSL calculates the optimum stocking level to achieve the desired spare part availability at the station. In doing so, it considers the importance of the part in preventing an outage,more » as well as key economic ordering parameters, such as part cost, carrying cost, number of parts in service, historical observed usage, anticipated future usage, and lead time to replenish.« less