Experimental verification of characteristic parameter analysis method for pipeline leak before break

Abstract The failure mode of the nuclear reactor main pipeline is often the first break and then leakage, i.e., Leak-Before-Break (LBB). If the LBB analysis technique of the pipeline is used in the design, the double-end shear fracture accident of the pipeline can be avoided. In this paper, it is assumed that an annular penetration crack already exists in the pipeline, and the tip-opening displacement of the crack and the leakage rate of the pipeline under high pressure are calculated by using LBB theoretical analysis. Then, according to the assumed conditions, the LBB test design of the pipeline under high pressure is carried out, and the crack tip opening displacement δ and the leakage rate Q of the pipeline under high pressure are measured through the experiments.