M油田A油层油井油套管防腐选材研究

Study on Anti-corrosion Material Selection of Casing and Tubing for Production wells of Reservoir A in M Oilfield

M油田A油层CO_(2)分压达0.1~0.2MPa,地层温度约80℃,Cl-质量浓度为140000 mg/L,为研究优选M油田A油层油井含CO_(2)环境的油套管钢,设计加工现场腐蚀挂片测量装置,在现场对6种低合金钢和不锈钢进行90天的挂片测试,发现低合金钢和低Cr钢发生严重局部腐蚀且平均腐蚀速率高;不锈钢13Cr和超级13Cr钢平均腐蚀率较低,可满足使用要求,综合考虑经济性、耐蚀性,推荐13Cr作为开发A油层的油套管钢。

The partial pressure of CO_(2) in layer a of M oilfield is 0.1-0.2 MPa,80℃,and the concentration of Cl-is 140,000 mg/L.In order to study and optimize the casing and tubing steels in CO_(2) environment in M Oilfield,the field corrosion testing device was designed and manufactured.The 6 materials coupons,including low alloy steels and stainless steels were tested for 90 days.It was found that the low alloy steels and low Cr steel had serious local corrosion and high general corrosion rates;however,the general corrosion rates of stainless steel 13Cr and super 13Cr steel were low,which could meet the use requirement,Considering the economy and corrosion resistance,13Cr is recommended as the casing and tubing steels for developing Reservoir A.