Study and analysis of the effect of dynamic load on the application of LBB technology to the primary pipe of reactor coolant system

Reactors may be subjected to dynamic loads, and in order to ensure that Leak-Before-Break (LBB) technology is safely and reliably applied to the primary piping of reactor coolant system, dynamic load impact analysis of LBB technology applied to the primary piping was performed. The dynamic mechanical properties test was carried out on the primary piping, and the crack leakage rate test under dynamic load and the impact load loading test under different loading speeds were carried out on the primary piping test piece with circumferential penetrating crack. Based on experimental data, the crack leakage rate analysis method and crack stability analysis method in quasi-static LBB technology were used to analyze the impact of applying LBB technology to the primary piping under dynamic load. The analysis results indicate that, when LBB technology is applied to the primary piping of reactor coolant system, the analysis results under dynamic load are more conservative than those under quasi-static load, and it is safer and more reliable under dynamic loads in practical engineering applications.