Environmental Fatigue and Fatigue Monitoring System in Korea

In accordance with the recommendation of USNRC and the U.S. license renewal experiences, the effect of reactor coolant environment on the fatigue life has to be considered for the continued operation of operating nuclear power plants as well as for the design of new plants in Korea. The reason is that it is very important to maintain the structural integrity and reliability of the nuclear power plants against the fatigue failure during operation. Fatigue monitoring system has been considered as a practical way to ensure safe operation of the nuclear power plants in terms of the fatigue. The fatigue monitoring system evaluates various plant conditions and their effects on the monitored location to give quantified value that indicates accumulated fatigue damage up to date. From this, the authors have developed a fatigue monitoring system, named NuFMS (Nuclear Fatigue Monitoring System) in web environment and has been being applied widely to Korean nuclear plants. In this paper, overall configuration and characteristics of the NuFMS are described in detail.