核电厂反应堆压力容器接管内圆角增强型目视检验技术研究

王羽翀　刘绪　吴化峰

【摘 要】核电厂需要定期对核岛关键设备如反应堆压力容器接管内圆角区域进行无损检验，从而发现可能存在的缺陷。ASME规范要求对接管内圆角区域实施超声检验，但由于接管内圆角区域结构复杂，且沿周向不断变化，超声检测实施难度较大，检测效率较低，按传统的方式对该区域实施超声检测困难较大。根据美国联邦法规10CFR50对ASME规范的补充要求规定：可采用高灵敏度的目视检验技术来代替超声检验执行容器接管内圆角区域的无损检验。本文结合法规的相关要求，介绍了反应堆压力容器接管内圆角增强型目视检验技术，并结合接管内圆角增强型目视检验检验系统开发的试验研究情况，得出使用特定的检验技术和检验系统，可满足反应堆压力容器接管内圆角检查的需求。

【关键词】核电厂；反应堆压力容器；接管内圆角；增强型目视检验

中图分类号： TM623 文献标识码： A 文章编号： 2095-2457（2018）08-0152-003

Research on enhanced visual inspection technology of reactor

pressure vessels nozzle inner radius in nuclear power plant

WANG Yu-Chong LIU Xu WU Hua-feng

【Abstract】Nuclear power plants need to conduct regular non-destructive testing of the key island nuclear equipment， such as reactor pressure vessel nozzle inner radius， to identify possible defects. The ASME Code requires that ultrasonic testing be performed on the nozzle inner radius area but due to the complicated structure of the nozzle inner radius area and varying circumferences， it is more difficult to perform ultrasonic testing and lower the detection efficiency. Ultrasound is performed on the area in a conventional manner testing is more difficult. According to the supplementary requirements of the US federal regulation 10CFR50 on ASME specification， the non-destructive testing of the nozzle inner radius area should be replaced by a high-sensitivity visual inspection technique. Combining with the requirements of the relevant laws and regulations， this paper introduces the enhanced visual inspection technique of reactor pressure vessel nozzle inner radius， and combined with the experimental research on the development of enhanced visual inspection and inspection system to nozzle inner radius， it is concluded that the use of specific inspection technique and Inspection system to meet the needs of reactor pressure vessel nozzle inner radius inspection.

【Key words】Nuclear power plant； Reactor pressure vessels； Nozzle inner radius； Enhanced visual inspection

0 前言

核電厂反应堆压力容器长期处于高温、高压、高辐射环境下运行，而反应堆压力容器的接管内圆角存在高应力区域，在热应力以及压力波动等作用下，该区域容易出现应力腐蚀裂纹或堆焊层表面损伤。国外核电厂在核一级设备接管内圆角区域曾经发现过裂纹，国内某核电厂停堆大修时也在反应堆压力容器出口接管不锈钢堆焊层上发现深度1.27mm的表面损伤痕迹[1]。

反应堆压力容器接管内圆角区域由于结构与载荷复杂，且长期处于应力集中的工况，因而有必要定期进行检查、监督，确保核电厂一回路压力边界的完整性[2]。……