Environmental Fatigue Evaluation of Top-Mounted In-Core Instrumentation Nozzle

상부 탑재형 노내계측기 노즐의 환경피로평가

Yoon, Hyo-Sub;Kim, Jong-Min;Maeng, Cheol-Soo;Kim, Gee-Seok;Kim, Hyun-Min

  • Received : 2016.03.28
  • Accepted : 2016.05.18
  • Published : 2016.06.30


The development of Top-Mounted In-Core Instrumentation(TM-ICI) is an ongoing project to reduce the risk due to severe accidents by inserting the instrumentation into a reactor closure head instead of a reactor bottom head. As part of this project, environmental fatigue analyses for TM-ICI nozzle have been performed using two methods of NUREG/CR-6909 and Code Case N-761. TM-ICI nozzle is subjected to transient loads for level A, level B and test conditions that should be evaluated for a fatigue analysis. It is found that a cumulative usage factor considering reactor coolant environment for TM-ICI nozzle is evaluated as less than 1, which is ASME Code allowable criteria of a fatigue analysis.


reactor pressure vessel;top-mounted in-core instrumentation nozzle;environmental fatigue evaluation


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Supported by : 한국에너지기술평가원(KETEP)