摘要
钻杆在海上气井测试中存在高温、高压、高含CO_(2)、高流速气体、砂等固体颗粒的冲刷等造成的腐蚀问题。通过高温高压反应釜模拟实验,对钻杆基体与两种钻杆涂层在总压43 MPa、温度140~170℃、CO_(2)分压在2.15~4.3 MPa、流速5 m/s范围内的冲刷腐蚀规律进行分析。实验结果表明,当总压为43 MPa,温度为170℃时,CO_(2)分压在2.15~4.3 MPa,流速5m/s,钻杆裸钢试样腐蚀速率接近,当CO_(2)分压升高至6.45 MPa时,腐蚀速率明显升高;当温度为140℃时,腐蚀浸泡时间为10 h,钻杆裸钢试样表面已生成较致密的腐蚀产物,随着浸泡时间的增加,消耗钻杆裸钢试样质量基本不变,其腐蚀速率显著降低。TK涂层与FT涂层在腐蚀模拟实验后均未出现开裂、起泡等情况。该研究表明在抗酸性流体冲刷腐蚀方面,TK与FT涂层钻杆在海上天然气探井测试作业中具备可行性。
Drill pipes used in offshore gas well testing encounter corrosion issues due to high temperatures,high pressures,high CO_(2)concentrations,and high-velocity gas flow containing solid particles like sand.By using a high-temperature,high-pressure autoclave simulation,the erosion-corrosion patterns of drill pipe substrates and two types of drill pipe coatings,under conditions of total pressure at 43 MPa,temperatures ranging from 140℃to 170℃,CO_(2)partial pressures between 2.15 MPa and 4.3 MPa,and flow velocities of 5 m/s,were analyzed.the experimental results show that at a total pressure of 43 MPa and a temperature of 170℃,with CO_(2)partial pressures ranging from 2.15 MPa to 4.3 MPa and a flow velocity of 5 m/s,the corrosion rates of bare steel samples were nearly constant.However,when the CO_(2)partial pressure increased to 6.45 MPa,the corrosion rate significantly increased.At 140℃,after 10 hours of corrosion immersion,a dense layer of corrosion products were formed on the surface of the bare steel samples,leading to a substantial reduction in corrosion rate over time as the mass loss stabilized.Both TK and FT coatings showed no cracking or blistering in the corrosion simulation tests.The study demonstrates that TK and FT coated drill pipes are feasible for application in well testing for offshore gas exploratory wells to resist acid fluid erosion-corrosion.
作者
黄伟
冯大龙
李三喜
冯佳琦
孙旭
孙吉星
HUANG Wei;FENG Dalong;LI Sanxi;FENG Jiaqi;SUN Xu;SUN Jixing(CNOOC China Limited,Shanghai Branch,Shanghai 200335,China;CNOOC Changzhou Paint and Coatings Industry Research Institute Co.,Ltd.,Shanghai Haikai Anti Corrosion Engineering Technology Branch,Tianjin 300452,China;Shanghai Engineering Technology Branch of CNOOC Energy Development Co.,Ltd.,Shanghai 200335,China)
出处
《油气井测试》
2024年第5期15-20,共6页
Well Testing
基金
中海石油(中国)有限公司上海分公司科研项目“高产高流速天然气测试对钻杆冲刷腐蚀评估”(ccl2022xhps002dm)。
