以在衬里背侧检漏孔下方存在一圆坑缺陷的尿塔为研究对象,进行有限元分析和应力腐蚀门槛值计算。结果表明:衬里背侧圆坑引起的应力集中为应力腐蚀的发生提供外部条件,在检漏蒸汽中氯离子的联合作用下最终造成圆坑处的应力腐蚀开裂。 Taking the existence of a pit with a round hole defect under the leak detection hole in the back of the lining as the research object, the finite element analysis and stress corrosion threshold calculation were carried out. The results show that the stress concentration caused by the circular dorsal line in the lining provides external conditions for the occurrence of stress corrosion. Under the joint action of chlorine ions in the leak test steam, the stress corrosion cracking at the circular hole is finally caused.