摘要
2011年6月,某核电厂大修期间对部分二回路小径管线进行了壁厚测量。发现部分给水管线和疏水管线的孔板下游直管段靠近孔板部位存在壁厚减薄现象。本文对其中的一根管线进行了失效分析。利用超声波测厚仪、等离子光谱发生仪、3D体视显微镜、扫描电镜等设备及相应的分析手段对减薄部位和未减薄部位进行了对比分析研究,结果表明管壁异常减薄是由于FAC引起的。利用fluent软件分析了孔板下游易于发生FAC的原因,在靠近孔板位置流体会形成漩涡,增加了传质速率,形成FAC敏感区。最后,针对FAC的风险管道,本文提出了相应的建议。
Small bore pipes were tested wall thickness during refueling outage. Some pipes downstream the orifice in feed water system and drain system were found wall thinning. This paper focused on one of the wall thinned pipes. Ultrasonic thickness meter, ICP, Stereo microscope, SEM were used to analysis the thinned region and the normal region. The result shows that wall thinning is caused by FAC（flow accelerated corrosion）. CFD method was further used to analysis FAC sensibility of downstream regions. Based on experience feedback, this paper put forward some suggestions.
出处
《全面腐蚀控制》
2016年第3期40-43,54,共5页
Total Corrosion Control
