腐蚀缺陷形状对套管损伤的影响  

Effect of Corrosion Defect Shape on Casing Damage

作　　者：幸雪松 张海龙 李朝玮 杨玉贵 武志强 易先中[2] XING Xuesong;ZHANG Hailong;LI Chaowei;YANG Yugui;WU Zhiqiang;YI Xianzhong(CNOOC Research Institute Co.,Ltd.,Beijing 100028,China;School of Mechanical Engineering,Yangtze University,Jingzhou 434023,China)

机构地区：[1]中海油研究总院有限责任公司,北京100028 [2]长江大学机械工程学院,荆州434023

出　　处：《腐蚀与防护》2025年第1期96-104,共9页Corrosion & Protection

基　　金：国家科技重大专项(2017ZX05032004-004);中海油生产项目。

摘　　要：针对焦页4HF井套管腐蚀问题,建立“套管-水泥环-地层”三维模型,通过热-应力耦合分析,研究了三种腐蚀缺陷形状对套管腐蚀后应力和剩余强度的影响。结果表明:温度对套管变形量影响较大,对压差的影响较小。凹槽形、圆球形和半圆柱形腐蚀区域的面积变化会导致腐蚀区域出现应力集中,应力集中是导致套管腐蚀失效的主要因素。当凹槽型腐蚀坑腐蚀宽度为5 mm时套管等效应力最大。当半圆柱形腐蚀坑腐蚀长度大于20 mm时,或者圆球形腐蚀坑腐蚀凹陷深度比大于70%时,套管达到屈服强度极限。三种腐蚀形状对套管应力和剩余强度的影响规律不尽相同。Aiming at the corrosion problem of casing in Jiaoye 4HF well,a three-dimensional model of“casing-cement sheathformation”was established.Through thermal stress coupling analysis,the influence of three corrosion defect shapes on the stress and residual strength of casing after corrosion was studied.The results indicate that temperature had a significant impact on the deformation of the casing,while the impact of pressure difference was relatively small.The area variation of groove shaped,spherical,and semi cylindrical corrosion areas could lead to stress concentration in the corrosion areas,which was the main factor causing casing corrosion failure.When the corrosion width of the groove type corrosion pit was 5 mm,the equivalent stress of the casing was the highest.When the corrosion length of the semi cylindrical corrosion pit was greater than 20 mm,or when the depth ratio of the corrosion depression of the spherical corrosion pit was greater than 70%,the casing reached the yield strength limit.The influence of three different corrosion shapes on the stress and residual strength of the casing was not the same.

关 键 词：套管腐蚀 腐蚀缺陷形状 套管应力 剩余强度 有限元分析 

分 类 号：TG174.4[金属学及工艺—金属表面处理]