Sensitivity study on the effects of nondestructive examinations on failure probabilities of reactor pressure vessels

Arai, Kensaku*; Katsuyama, Jinya  ; Li, Y. 

We have developed an analysis code called PASCAL for assessing failure frequencies of RPVs based on probabilistic fracture mechanics. In failure frequency analyses, flaw size distribution in RPVs is one of the most important parameters, and it is determined by considering possible flaws generated during fabrication and the flaw-detection capabilities of nondestructive examinations (NDEs). In this study, the effects of NDEs on failure frequencies of RPVs are evaluated using PASCAL considering probability of detection (POD) in terms of minimum detectable flaw size, the smallest probability of non-detection (PND), and flaw size where POD value reaches the smallest PND.