长庆气田Su11井试水和套管腐蚀工程试验研究

为达到经济有效地开发长庆某气田的目的，需对该气田洛河组、直罗组、延安组和延长组的地下水层的腐蚀特征进行研究，为此在Su11井开展了为期近两年的逐层试水和套管腐蚀工程试验，采用井口快速取样和井下高压物性取样分析，全面分析了各层水的物性参数。在明确各层水对套管的腐蚀机理基础上，利用高温高压釜、磁阻测试和井下挂环试验等研究了N80套管钢在各水层原始地层条件下的腐蚀特征，得出了该气田延长组水腐蚀速率为0.131～0.327 mm/a、对套管的外腐蚀相对明显的结论，据此提出了不同固井条件下的防腐建议。

TRAIL STUDY OF WATER TEST AND CASING CORROSION ENGINEERING OF SU-11 WELL IN CHANGQING GAS FIELD

In order to economically and effectively exploit a gas field of Changqing, it was necessary to study the corrosion characteristics of subsurface aquifers of Luohe, Zhiluo, Yan'an and Yanchang series. For this sake, two-year experiment of aquifer test and casing corrosion engineering was performed in the well Su-11. Wellhead quick sampling and down-hole PVT sampling had been done to analyze the physic properties of those aquifers. On the basis of understanding casing corrosion mechanism, autoclave and magnetic reluctance test, etc., were used to infer the corrosion characteristics of N80 casing steel under the circumstances of original formation aquifer. It was concluded that the corrosion rate is 0.131-0.327 mm/a in Yanchang series of this gas field, based on which corrosion prevention suggestion was provided for various well cementing conditions.