某油田注水井N80油管腐蚀失效分析  

Corrosion Failure Analysis of N80 Tubing in Water Injection Well of a Certain Oilfield

作　　者：程利民 吴绍伟 宋洋 劳文韬 袁梦瑶 胡莎莎 胡楠 蒋文瑞 CHENG Limin;WU Shaowei;SONG Yang;LAO Wentao;YUAN Mengyao;HU Shasha;HU Nan;JIANG Wenrui(China National Offshore Oil(China)Co.,Ltd.,Zhanjiang Branch,Zhanjiang 524057,Guangdong,China;Xi'an Maurer Petroleum Engineering Laboratory Co.,Ltd.,Xi'an 710065,China)

机构地区：[1]中海石油(中国)有限公司湛江分公司,广东湛江524057 [2]西安摩尔石油工程实验室股份有限公司,西安710065

出　　处：《焊管》2024年第9期62-68,共7页Welded Pipe and Tube

基　　金：中国海洋石油集团有限公司重大科技项目“南海西部在生产油气田提高采收率技术研究”(项目编号CNOOC-KJ 135 ZDXM 38 ZJ 01 ZJ)。

摘　　要：为了避免某油田注水井N80油管在服役过程中发生腐蚀穿孔破损,提高注水井管道使用寿命,采用测量、金相、成分分析、力学性能分析、扫描电镜、能谱分析、X射线衍射等方法对失效油管进行了分析。结果表明,失效油管的化学成分和力学性能符合标准要求,失效原因主要是水体结垢,在管柱内壁形成垢下封闭环境,导致垢下局部腐蚀,且水中Cl^(-)含量较高,在Cl^(-)的渗透、催化作用下,腐蚀程度不断加剧。且由于CO_(2)及H_(2)S酸性介质的存在,也会导致管柱发生CO_(2)及H_(2)S腐蚀。多种腐蚀协同作用导致油管发生了较为严重的局部腐蚀,随着局部腐蚀的逐渐进行,最终形成腐蚀穿孔。在后续使用过程中采用缓蚀阻垢剂对管柱进行防护,从而减弱结垢对管壁造成的腐蚀,提高油管服役寿命。In order to avoid perforation damage to the N80 tubing of a water injection well in a certain oilfield during service,and to improve the service life of the water injection well pipeline,measurement,metallography,composition analysis,mechanical property analysis,scanning electron microscopy,energy spectrum analysis,and X⁃ray diffraction were used to analyze the failed tubing.The results show that the chemical composition and mechanical properties of the failed oil pipe meet the standard requirements,the main reason for failure is that the water scaling,and a closed environment under the scale is easily formed on the inner wall of the pipe column,leading to local corrosion under the scale.In addition,the Cl^(-)content in the water is high,and under the permeation and catalytic action of Cl^(-),the degree of corrosion continues to intensify.And due to the presence of acidic media such as CO_(2)and H_(2)S,it can also lead to CO_(2)and H_(2)S corrosion of the pipe column.The synergistic effect of multiple corrosion causes severe localized corrosion of the oil pipe,which gradually progresses and eventually forms perforation damage.Corrosion and scale inhibitors can be used for column protection during subsequent use,thereby reducing the degree of scaling and corrosion on the pipe wall and improving the service life of the oil pipe.

关 键 词：N80油管 垢下腐蚀 局部腐蚀 腐蚀穿孔 

分 类 号：TE983[石油与天然气工程—石油机械设备] TG172.8[金属学及工艺—金属表面处理]