On-line Monitoring for Improving Performance of Nuclear Power Plants

Book excerpt: This report extends the application of on-line monitoring to equipment and process condition monitoring, encompassing an array of technologies including vibration monitoring, acoustic monitoring, loose parts monitoring, motor current signature analysis and noise diagnostics, as well as vibration analysis of the reactor core and the primary circuit. Furthermore, this report includes the application of modeling technologies for equipment and process condition monitoring. A majority of these technologies depend on existing data from existing sensors and first principles models to estimate equipment and process behavior using empirical and physical modeling techniques. In doing so, pattern recognition tools such as neural networks, fuzzy classification of data, multivariate state estimation and other means are used. These means are described in the report, and examples of their application and implementation are provided. The benefits of OLM for performance verification of process instruments were described in the first report and included such advantages as the ability to extend the calibration interval of pressure, level and flow transmitters, detection of blockages, voids and leaks in pressure sensing lines, detection of degradation of the dynamic response of process instruments, and the like. Examples of benefits of OLM for condition monitoring include: (1) the ability to determine the onset of failure of pumps, valves, motors and reactor vessel components; (2) residual life assessment of equipment; (3) equipment life extension and aging management; (4) the ability to establish objective schedules for preventive maintenance, equipment refurbishment or replacement; and (5) maintenance cost reduction, efficiency improvements, reduction of plant outages, and reduction of radiation exposure to plant personnel.--Publisher's description.