Practical aspects of applying risk-based approaches in asset management for power plant

Risk-based approaches can help in selecting and prioritizing future choices and schedules so that decisions are justified by the associated risk. The paper will give examples of applications from conventional power plants, where degrading physical condition can increase the risk of failure and decrease asset value: a single detailed example illustrated the approach, which is also anchored in the new European standard EN 16991 (prEN 16991:2016) and applied in large-scale industrial projects world-wide. To manage the risk, implemented inspections and maintenance can help to limit the probability of failure (PoF) and its uncertainty. Failure statistics of similar components operating in similar environments may provide fair estimates of PoF, but biased or lacking comparable statistics may require adjustment through e.g. additional measurements or expert information for the application. In parallel, inspection and monitoring data can more directly help in assessing the evolution of PoF. An example of the latter is a power plant heat exchanger, with inspection and failure criteria considered for a full life cycle that included multiple inspections by the same inspecting party and equipment. Uneven spatial distribution of in-service wall loss without changes in mechanisms or loss rates at a given location nevertheless required a change of inspection strategy during the life cycle.