In this paper,a preliminary study is conducted on the scouring corrosion law of two types of internal coatings of drilling pipes for gas well testing under different factors.Through the experiments of high-pressure and high-flow rate multiphase flow loop equipment and high-temperature and high-pressure reactor,different influencing factors including temperature,CO2 content,environmental pH,sand content and flow rate are analyzed,and the scouring corrosion resistance of the coatings is characterized by coating thickness,adhesion,hardness and electrochemical resistance.The experimental results show that the inner coating of the drill pipe is less affected by the scouring corrosion under the conditions of high temperature,high CO2,low pH and high flow rate,however,the impedance of the coating in the low-frequency region is seriously reduced and the surface of the coating appears to be damaged under the conditions of sand or water-carrying sand.It is revealed that the inner coating of the tested drill pipe should not be used in a sandy environment and it has excellent scour corrosion resistance in a sand-free environment.
关键词
测试钻杆/内涂层/粉末涂料/电化学阻抗/冲刷腐蚀
Key words
test drill pipe/internal coating/powder coating/electrochemical impedance/washout corrosion
维普
万方数据