Power station assessment and failure investigation
Power stations are becoming assessed more frequently to determine their integrity and remaining safe life on a periodic basis. As codes do not exist to aid directly in this, and design codes are not applicable, new fitness for service codes are under development in several countries through various technical organizations. A discussion is presented about the assessment methodologies being developed, with particular reference to those of ASME and API, based on risk based inspection. Some examples of problems discovered during assessments of power plants are described, as well as some investigations of specific failures that have occurred in such units.