核电工程控制棒驱动机构Ω环水压试验后PT显示问题的处理

The Problem and Treatment Showed in PT Test after Hydraulic Testing of Control Rod Driving Mechanism Ω Ring in Nuclear Power Project

文章论述了CRDM Ω环焊接完成后水压试验后在进行液体渗透检验后在母材区域存在圆形显示时所采取的应对措施,从母材的制造标准及现场焊接的标准对照方面入手,分析了制造与焊接时PT验收时的标准的应用差异是造成PT显示的主要原因,通过对显示区域的表面扫描电镜检查、金相检验、理化检测,水压试验与PT显示的关系分析,提出了照用、打磨及打磨后补焊、采用西屋的CSCA预防措施及最终的WSI公司的Overlay四种方式,为核电工程对于Ω环显示问题的处理提出了权威性解决措施。

This paper discusses the solutions to liquid PT test circular display existed in base metal area after hydraulic testing when the CRDM Ω ring welding is finished. According to the contrast of base metal manufacturing standards and the field welding standards, this paper finds the primary cause of PT test is the difference of PT testing codes used in manufacturing and welding. With the surface scanning electron microscopy, metallographic examination, physical and chemical testing of the display area, and analysis of the relationship between the hydraulic pressure test and PT display, the four measures： illumination, polishing and grinding after welding, the Westinghouse CSCA preventive measures and the final WSI Overlay, as authoritative solutions for nuclear power project in dealing with the ~ ring display problem are proposed.