E-Book Overview
RESEARCH REPORT, VTT-R-00416-11,Otso Cronvall and Ilkka Männistö,34p,2011 This study mainly concerns analysis applications related to OECD Pipe Failure Database OPDE. This database covers all this far experienced nuclear power plant (NPP) piping degradation/failure mechanisms. The scope of potential OPDE database applications is relatively large. Examples of some notable OPDE applications carried out this far are reviewed in this study. From the viewpoint of probabilistic fracture mechanics (PFM) and risk informed in-service inspection (RI-ISI) applications the most useful ones of these applications are the Markov model for piping degradation state analysis by Fleming [8] and the R-Book Project approach for producing reliability data for piping components in Nordic NPPs by Lydell and Olsson [16], respectively. It is concluded that OPDE data alone do not suffice for estimation of formation frequency and sizes of initial cracks nucleating during service in NPP piping components. For this purpose supplementary data concerning mainly smaller non-through wall flaws, size/shape data of all cracks and piping component populations are needed. These results on the applicability of OPDE were expected, as this database has not been primarily intended for statistical estimates concerning initial cracks. However, as OPDE is continuously developed further, it may in the future be better applicable for this purpose.For estimation of leak/break frequencies of NPP piping components during service, data concerning e.g. their detected occurrences and occurrence relevant locations are needed. It is concluded that presently OPDE data alone do not suffice for estimation of leak/break frequencies of NPP piping components during service. For this purpose supplementary data concerning piping component populations are needed. However, besides this shortcoming the OPDE data are sufficient for this purpose.
E-Book Content
VTT-R-00416-11
RESEARCH REPORT
Applications concerning OECD Pipe Failure Database OPDE Authors:
Otso Cronvall and Ilkka Männistö
Confidentiality:
Public
RESEARCH REPORT VTT-R-00416-11 1 (34)
Report’s title
Applications concerning OECD Pipe Failure Database OPDE Customer, contact person, address
Order reference
State Nuclear Waste Management Fund (VYR) and Technical Research Centre of Finland (VTT) Project name
Project number/Short name
PURISTA
41253/Purista-2010
Author(s)
Pages
Otso Cronvall, Ilkka Männistö
34/ -
Keywords
Report identification code
Crack, initial crack, leak, break, database, OPDE, SCAP
VTT-R-00416-11
Summary
This study mainly concerns analysis applications related to OECD Pipe Failure Database OPDE. This database covers all this far experienced nuclear power plant (NPP) piping degradation/failure mechanisms. The scope of potential OPDE database applications is relatively large. Examples of some notable OPDE applications carried out this far are reviewed in this study. From the viewpoint of probabilistic fracture mechanics (PFM) and risk informed in-service inspection (RI-ISI) applications the most useful ones of these applications are the Markov model for piping degradation state analysis by Fleming [8] and the R-Book Project approach for producing reliability data for piping components in Nordic NPPs by Lydell and Olsson [16], respectively. It is concluded that OPDE data alone do not suffice for estimation of formation frequency and sizes of initial cracks nucleating during service in NPP piping components. For this purpose supplementary data concerning mainly smaller non-through wall flaws, size/shape data of all cracks and piping component populations are needed. These results on the applicability of OPDE were exp