Role of Prognostics in Support of Integrated Risk-based Engineering - A Review in Respect of Nuclear Power Plant Safety

The present approach of plant surveillance employs, on-line monitoring of process parameters, periodic in-service inspection, condition monitoring, etc. To make these program more effective there is growing application of risk-based / risk-informed approach to plant surveillance. However, risk-based approach in the present form is ‘static’ in nature, and based on probabilistic methods. It is expected that to cater to real-time challenges the approach should be dynamic in terms on-line monitoring that employing deterministic and probabilistic methods in an integrated manner. The available literature suggests that extensive efforts are being made to upgrade / modify existing condition based approach to prognostic approach. There is a general appreciation of the fact that the prediction capabilities in surveillance programm in general and conditioning monitoring approach in particular can be improved significantly through prognostic approach. This paper reviews prognostics approach that enabled assessment of remaining life of the components in complex engineering systems with a special reference to nuclear plants where safety forms the major objective function.