Stock Effects on Exceptional Maintenance Tasks Taking Into Account Risks

Exceptional maintenance tasks are maintenance tasks that are unlikely to be carried out more than once or twice over the life of a Nuclear Power Plant. Such a task may be preventive or corrective toward a wearing mechanism that may lead to a failure with a low probability and high potential consequences. Exceptional maintenance tasks are often characterized by a long lead-time and a high cost, that’s why in addition to the classic maintenance issue on choosing between preventive or corrective tasks, it is very important for exceptional maintenance to evaluate the best stock level. This paper describes the methodology and tools that are being developed at EDF and presents a case study that has been carried out.Copyright © 2006 by ASME