Demonstration of leak-before-break in Japan Sodium cooled Fast Reactor (JSFR) pipes

Regulatory Considerations Regarding Potential High Temperature Fluid Releases in Advanced Reactor Designs

“…must be satisfied. There has been recent work internationally regarding analyses and experiments to demonstrate the applicability of the LBB approach to different sodium piping designs [94][95][96]. For SFR vendors seeking to utilize the LBB approach as part of their design, the central factor is the demonstration of applicability of the approach for the specific piping under consideration.…”

Effect of local plastic component on crack opening displacement and on J-integral of a circumferential penetrated crack

“…In such materials with small work hardening, the local plastic component has a large influence on the evaluation of J-integral and COD even when used below the yield stress. In order to evaluate local plastic component accurately, the authors divided the evaluation formulas for J-integral and COD into elastic, local plastic and fully plastic components, and formulated them as follows (Wakai et al, 2014(Wakai et al, , 2018.…”

“…where, subscript E, LP and FP show elastic, local plastic and fully plastic components, respectively. Since elastic and fully plastic components have already been proposed in previous studies and verification with the GE-EPRI method has also been completed (Wakai et al, 2014(Wakai et al, , 2018, the local plastic component in the evaluation of Jintegral and COD was highlighted in this study, and an evaluation method was developed especially for small work hardening materials whose influence strongly appears. Elastic, plastic and elastic-plastic FEA were performed and Jintegral and COD due to the local plastic component were obtained by subtracting the results of elastic and plastic analysis from the results of elastic-plastic analysis.…”

“…In the calculation of J-integral, virtual crack extension method was employed. Analytical function of the code has been verified in a previous report (Wakai et al, 2014(Wakai et al, , 2018. Isoparametric 20-node three-dimensional hexahedral element (HEX20) was used in the analyses.…”

Effect of thermal aging on the leak-before-break analysis of nuclear primary pipes

“…Gong et al (2013) and Du et al (2013) applied a LBB approach to a dissimilar metal welded joint connecting safe end to pipe-nozzle of an AP1000 reactor pressure vessel. Yoo and Huh (2013) and Wakai et al (2013) demonstrated that the LBB assessment procedure is applicable to piping systems of FBRs.…”