核电厂镍基焊缝应力腐蚀开裂返修技术分析

Analysis on the Repair Technology for Nickel-based Weld Stress Corrosion Cracking in Nuclear Power Plant

在压水堆核电厂运行服役阶段,容易出现镍基焊缝在一回路冷却剂环境下的应力腐蚀开裂情况。根据ASME BPVC规范,针对缺陷去除、管道对接焊缝外表面堆焊、管道对接焊缝内表面堆焊或镶嵌焊接、J形焊缝外表面堆焊、J形焊缝贯穿管内端返修、J形焊缝贯穿管外端返修、J形焊缝机械密封返修等多种返修技术进行识别、分析和讨论,可以为核级承压容器镍基焊缝的返修技术选择提供参考。

To solve the problem that the stress corrosion cracking of the nickle-based weld normally occurs with the primary circuit coolant in pressurized water reactor nuclear power plants during operation,identifications,analyses and discussions were conducted on following repair technologies according to ASME BPVC standards,such as flaw removal,piping butt weld overlay,piping butt weld inlay or onlay,J groove weld embedment,J groove weld internal mid-wall surface repair,J groove weld outer surface pad repair,and J groove weld mechanical seal repair.This may serve as a reference for the repair technology selection of the nickle-based weld in nuclear pressure vessels.