Recently, it is reported that axial and circumferential PWSCCs (primary water stress corrosion crackings) occurred on the dissimilar welds of steam generator drain nozzles in PWR. In this study, the PWSCC is assessed via residual stress analysis, PWSCC initiation review and growth assessment. The residual and operating stress distributions are calculated by finite element method. Based on the stress analysis results, PWSCC initiation locations are predicted by comparing between the stresses and PWSCC threshold stress value. The predicted locations are compared with the examination results by using penetration, eddy current and destructive tests. It is found that the PWSCC initiation prediction has good agreement with the examination results. Also, PWSCC growth is assessed by using the PWSCC growth analysis procedure presented in ASME B&PV Code, Sec.XI. Finally, it is identified that the penetration time via growth assessment has reasonable agreement with the real one.

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