摘要
为加强保障海上油气井安全生产,有效应对井下油套管腐蚀问题,以渤海C油田某生产井为例,基于Q/HS 14015—2018标准,建立沿井深的选材图版,提出初步待选材质;然后,结合室内腐蚀实验和微观表征手段进一步研究其腐蚀机理,并基于API TR 5C3标准校核所选管材的剩余强度以及预测其服役寿命。研究结果表明:环境介质中主要腐蚀物质为O_(2)、Cl^(-);无论是液相环境还是气相环境,管柱点蚀速率远大于管柱均匀腐蚀速率,液相环境中不同材质的点蚀速率由大到小为碳钢>3Cr>9Cr>13Cr;由于油田要求油管至少安全服役5 a,套管至少安全服役25 a,C油田油管可以选用3Cr,可以保障油管9 a安全服役,95/8″套管采用9Cr材质时,可以安全服役25 a,而7″套管至少采用13Cr,才能满足25 a的安全服役要求。研究结果可为后续区块开发设计提供管柱防腐选材参考。
In order to enhance the work safety of offshore oil and gas wells and cope with the problem of downhole oil tubing and casing corrosion effectively,taking a production well of Bohai C oilfield as an example,a material selection plate along the well depth was established on the basis of Q/HS 14015—2018 standard,and the preliminary materials to be selected were proposed.The corrosion mechanism was further investigated by combining indoor corrosion test and microscopic characterization method,then the residual strength of the selected pipeline materials was calibrated based on API TR 5C3 standard,and their service lives were predicted.The results show that the main corrosive substances in the environmental medium are O_(2)and Cl^(-).The pitting corrosion rate of pipe string is much higher than the uniform corrosion rate of same string in both liquid and gas environments.The pitting corrosion rates of different materials in the liquid phase environment is,in descending order,carbon steel>3Cr>9Cr>13Cr.As the oilfield requires at least 5 years of safe service for oil tubing and 25 years for casing,3Cr can be used for tubing in C oilfield,which can ensure the safe service of tubing for 9 years.When 9Cr is used for 95/8″casing,it can ensure the safe service for 25 years,while 13Cr is used for 7″casing at least,so as to meet the requirements of safe service for 25 years.The results can provide a reference for selecting corrosion-resistant materials of tubular column in the design of subsequent block development.
作者
张智
丁宸宇
李进
赵苑瑾
蔡楠
ZHANG Zhi;DING Chenyu;LI Jin;ZHAO Yuanjin;CAI Nan(State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu Sichuan 610500,China;CNOOC(China)Co.,Ltd.Tianjin Branch,Tianjin 300450,China)
出处
《中国安全生产科学技术》
CAS
CSCD
北大核心
2023年第11期100-107,共8页
Journal of Safety Science and Technology
基金
国家自然科学基金项目(U22A20164,52074234)
四川省科技计划项目(2020JDTD0016)
中国石油天然气股份有限公司-西南石油大学合作项目(2020CX040100)。
关键词
海上油田
CO_(2)腐蚀
选材图版
防腐选材
腐蚀实验
剩余强度
服役寿命预测
offshore oil field
CO_(2)corrosion
material selection plate
corrosion-resistant material selection
corrosion test
residual strength
service life prediction
