沙念油田套管腐蚀行为研究

Research on casing corrosion behavior in Shanian Oilfield

随着开发时间的延长,因腐蚀引起的套损井的数量不断增加,严重影响了沙念油田的正常生产。为摸清沙念油田套管腐蚀规律,为制定套管防腐技术措施提供科学依据,利用新型的井下CO2动态腐蚀模拟试验装置进行了室内不同CO2分压、温度、流速等因素控制下套管腐蚀速率的测定,并在此基础上对套管腐蚀行为进行了研究。试验结果表明:N80套管钢的腐蚀速率随CO2分压、温度和流速的增加而增加,局部腐蚀严重,腐蚀产物以Fe CO3为主。

As the extension of the production time in Shanian Oilfield,the regular production has been seriously affected by the increasing number of casing damage wells which caused by corrosion. With the purpose of providing scientific basis for the set of casing corrosion protection technology measures,casing corrosion regularity in Shanian Oilfield should be figured out. By the using of a new dynamic simulation test device for the CO2 corrosion of the casing near downhole pump suction port,the rate of casing corrosion in the laboratory under the limit of different partial pressure of CO2,temperature and flow velocity is measured,and the casing corrosion behavior is researched. The results show that the corrosion rate of N80 steel casing increases following the partial pressure of CO2,temperature and flow velocity; localized corrosion is serious; the corrosion products mainly include Fe CO3.