Advanced Diagnostics and Prognostics for Safety-Related NPP equipment, USA (Deadline: 4 March 2010)23 February 2010
NRC Staff is interested in exploring the current state of the art in this area, and in gaining insight into aspects of this area that are presently under investigation and which may be expected to become feasible within the next several years.
Michele D. Sharpe,
12300 Twinbrook Parkway
Rockville, Maryland 20852-2738
Mechanical equipment typically exhibits indication of impending failure well before a failure has actually occurred. For example, the acoustic noise produced by a severely worn but still functional bearing assembly is noticeably different from the noise produced when the bearings are new. Various technologies facilitate the monitoring and interpretation of these indications, and provide insight into the condition of the equipment and may even facilitate estimation of remaining life. With these insights, plant personnel can schedule maintenance in anticipation of failures. Such insights may help to determine whether near term emergency maintenance is warranted to avoid equipment failure, or whether it would be reasonable to delay action until the next scheduled maintenance period.
Digital equipment, such as may be used for plant protection and control, typically has self test features and may have automatic calibration verification, automatic recalibration, and other advanced features designed to improve performance and availability.
The Technical Specifications (TS) for a nuclear power plant mandate inspection and maintenance activities for plant equipment, including evaluation of readiness and performance, and including evaluation of instrument calibration. AD&P may be useful in evaluating and possibly altering the scheduling and nature of those inspections and maintenance activities. With an effective AD&P program, it may be reasonable to extend some of the inspection and maintenance intervals. Or, AD&P may reveal a need for inspection and maintenance activities that are not included in the TS but which should be performed anyway and possibly considered for inclusion in the TS.
NRC Staff is interested in exploring the current state of the art in this area, and in gaining insight into aspects of this area that are presently under investigation and which may be expected to become feasible within the next several years. Ultimately, NRC Staff will need to determine what, if any, changes to NRC regulations or guidance may be appropriate in anticipation of the use of these technologies in connection with plant mechanical and digital equipment.