Corrosion on bench slope between oil tubing and collar is an important damage, which always results in leakage of oil tubing under high pressure. Weight loss, morphology and electrochemical test were adopted to investigate the crevice corrosion susceptibility of tubing and collar steels in FeCl3 solution and oilfield produced liquid. The tubing steel presents lower crevice corrosion resistance than collar steel. An additional capacitance in high frequency range is found while crevice corrosion occurs. Pitting dominates the corrosion form in crevice. Thus, the failure of bench slope is mainly caused by the crevice corrosion of oil tubing. Degree of the crevice corrosion increases with the elevating temperature and then decreases.%台阶面腐蚀是油管和接箍接头腐蚀失效的重要形式,进而在高压下使油管渗漏.采用腐蚀失重、形貌分析和电化学测试,研究了FeCl3溶液和油田采出液中某油田油管钢和接箍钢的缝隙腐蚀敏感性,结果表明,油管钢抗缝隙腐蚀能力比接箍钢低,缝隙腐蚀产生后,交流阻抗增加一个高频容抗,缝隙内呈现点蚀特征,油管和接箍接头台阶面以油管的缝隙腐蚀为主.随着温度升高,缝隙腐蚀程度先增大后减小.
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