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目的：东海A气田开发储层流体中CO2分压约1.85 MPa，温度在150℃左右。井下腐蚀环境已超出中海油选材图版的应用范围，因此应进行防腐模拟实验研究，为优选油套管材质提供依据。方法应用失重法在高温高压动态反应釜中进行高温高压动态腐蚀模拟测试，选择油气田开发中高防腐油套管常用的普通13Cr、超级13Cr、22-25Cr双相不锈钢3种材质试样，测试不同材质油套管井下的腐蚀速率。结果 CO2分压2.0 MPa下，130℃时3种材质均未发现局部点蚀，温度升至150℃时，超级13Cr和22-25Cr双相不锈钢表现为均匀腐蚀，普通13Cr材质出现了点蚀，点蚀速率为0.6413 mm/a，明显超过了腐蚀控制线；150℃下，随着CO2分压的增加，腐蚀速率增加，但分压达到约2.0 MPa后，腐蚀速率增加减缓，并且出现下降趋势。结论从井底开发储层到地面，温度逐步降低，根据实验结果，东海 A 气田开发设计组合油套管的方式防腐，深部温度高于130℃位置的油套管应用超级13Cr材质，上部温度低于130℃位置的油套管应用普通13Cr材质，以降低成本。

ABSTRACT:Objective The content of CO2 partial pressure of the development reservoir fluid on the Gas Field A in the East China Sea is about 1.85 MPa, and the temperature is about 150℃. The parameters of downhole corrosion environment are out of the application scope of CNOOC tube and casing material selection chart, therefore, corrosive simulation experimental research should be carried out, which provides the foundation for optimization of tube and casing material.Methods In the ex-periment, weight loss method was used to dynamically test the corrosion rates of different tube and casingmaterials under the downhole condition by HTHP Auto Clave. The material samples were ordinary 13Cr, super 13Cr and 22-25Cr duplex stainless steel, high anticorrosive tubing and casing, which are commonly used in oil and gas field development.Results The results of experiment showed that localized pitting wasn’t found in 3 kinds of material samples under the condition of CO2 partial pressure at 2 MPa and 130℃; when the temperature rose to 150℃, uniform corrosion characteristic was present for super 13Cr and 22-25Cr duplex stainless steel, pitting was present on ordinary 13Cr, and the pitting rate was 0.6413 mm/a, which significantly exceeded the corrosion control line. When the temperature was below 150℃, with the increase of CO2 partial pressure, the corrosion rate increased, but after CO2 partial pressure exceeded 2.0 MPa, the increase of corrosion rate became slow, and the trend of decline occurred. From the bottom of a well-developed reservoir to the ground, the temperature was gradually reduced. Conclusion According to the experimental results, the development of the Gas Field A in the East China Sea designs the means of combination of tube and casing in ordor to protect corrosion, super 13Cr materials should be used in the deep location at temperature higher than 130℃, while ordinary 13Cr should be used in the upper location at temperature below 130℃, which could realize the cost saving of tube and casing.