An Application of the probabilistic fracture mechanics code PASCAL-SP to risk informed in-service inspection for piping

Mano, Akihiro; Yamaguchi, Yoshihito; Katsuyama, Jinya; Li, Y.

Proceedings of Asian Symposium on Risk Assessment and Management 2017 (ASRAM 2017) (USB Flash Drive), 12 Pages, 2017/11

As a rational inspection methodology, risk informed in-service inspection (RI-ISI) has been widely utilized in in-service inspections of nuclear power plants (NPPs) in several countries. In some of NPPs, an RI-ISI methodology developed by Westinghouse Owners Group (WOG) was applied. As a part of RI-ISI process, extent of examination for important piping segments are determined through the comparisons of leak frequencies with its target value based on the industrial piping leak experiences. The leak frequencies for segments are used as a numerical factor for planning examination based on WOG methodology, and can be evaluated through analyses on the basis of probabilistic fracture mechanics (PFM). In Japan Atomic Energy Agency (JAEA), we have developed a PFM analysis code PASCAL-SP for evaluating leak and rupture probabilities or frequencies of welds in piping of light water reactors taking crack initiation and propagation due to aging degradation mechanisms such as fatigue into consideration. Also, evaluation models of probability of crack detection by non-destructive examination considering the crack type, crack depth and performance of examination team is incorporated in PASCAL-SP. In this study, we investigated the applicability of PASCAL-SP into planning of examination considering the effects of repair methodology, performance of inspection team, and examination time. On the basis of analysis results, it was found that examination plans can be reasonably determined by using PASCAL-SP under several conditions, and it was concluded that the PFM is very effective tools in RI-ISI.

Development of an in-service inspection technique for the intermediate heat exchanger tubes of the High-Temperature Engineering Test Reactor

Inagaki, Yoshiyuki; ; *; *; *

Nuclear Technology, 104, p.106 - 117, 1993/10

https://doi.org/10.13182/NT93-A34873

no abstracts in English

Performance test of inservice inspection equipment for HTTR intermediate heat exchanger tubes

Inagaki, Yoshiyuki; ; *; *; *; *

JAERI-M 92-151, 49 Pages, 1992/10

JAERI-M-92-151.pdf:1.57MB

no abstracts in English