摘要
西部某油田不等壁厚焊接钢管发生腐蚀穿孔泄漏,为此,对管道的外观、壁厚、焊缝、化学成分、金相组织及腐蚀产物等进行了检测分析。结果表明:管道穿孔的主要原因是在高矿化度水工况下,在含有大面积未焊透缺陷的焊缝区出现了CO_2腐蚀,同时内壁的焊缝处台阶改变了流体的流速流态,管道内流体不稳定的流动方式以及高浓度Cl^-的作用导致管道内壁腐蚀产物膜的不断破坏,加快了腐蚀速率。
Corrosion perforation occurred in a welded steel pipeline of unequal wall thickness in a western oilfield. Through appearance inspec- tion, wall-thickness measurement, radiographic inspection, chemical composition analysis, metallographic examination and corrosion products analysis, the cause of the pipeline perforation was analyzed. Results showed that the main reason was the corrosion of carbon dioxide （ CO2 ） in the incomplete-penetration weld under high salinity water. At the same time, the flow rate and the regime were changed by the steps of the welds, and the fluid instabilities and the high concentrations of Cl^- within pipeline led to the continual damages of corrosion products, increas- ing the corrosion rate.
作者
宋成立
朱丽霞
周飞
武刚
丛深
SONG Cheng-li;ZHU Li-xia;ZHOU Fei;WU Gang;CONG Shen(CNPC Tubular Goods Research Institute, Xi＇ an 710077, China;PetroChina Tarim Oilfeild Company, Korla 841000, China)
出处
《材料保护》
CAS
CSCD
北大核心
2018年第3期131-135,共5页
Materials Protection
关键词
管道
腐蚀
穿孔
不等壁厚
失效分析
pipeline
corrosion
perforation
unequal wall thickness
failure analysis
