目的 分析输油管道腐蚀泄露失效的主要原因。方法 对输油管道泄漏失效进行了深入调查研究，分析了输油管道失效样品，对泄漏孔形貌、几何参数、理化性能、金相组织进行了试验分析，并在泄漏穿孔处取样进行了电子显微镜扫描、微区能谱分析。结果 经化学分析、力学性能和金相组织等理化检验分析，该失效输油管道的材料理化性能符合GB/T 8163—2008标准的相应要求及用户要求。从穿孔宏观形貌分析来看，腐蚀区域面积较大，管道内壁存在大量腐蚀产物，穿孔位于输送管道的下部，最大腐蚀深度达3.5 mm，且管道中存在大量临界腐蚀坑电子显微镜下放大观测，能看到表层覆盖有疏松的腐蚀产物，微区能谱分析显示腐蚀产物中含有大量的Cl、C、O和Fe等元素。结论 材料性能并不是造成输油管道失效事故的主要原因，输油管道泄漏主要是由管体内壁点腐蚀穿孔造成的，引起腐蚀穿孔的主要因素为输送流体介质中的Cl?，当管材基体中的Fe不断被Cl?腐蚀溶解后随流体介质迁移，点蚀坑迅速扩展，最终导致腐蚀穿孔。

Objective To analyze the main causes of oil pipeline corrosion leakage. Methods An investigation research on the accident was developed and the samples of perforation leakage were analyzed. Perforation morphology, geometric parameters, physical and chemical properties and microstructure were analyzed. Samples taken at the leakage and perforation point were analyzed by electron microscope scanning and EDAX. Results Chemical analysis and physical and chemical inspection for mechanical property and microstructure showed that the physicochemical properties of oil pipeline met GB/T 8163—2008 requirements and user requirements. According to the macroscopic pattern of perforation point, the pipeline with large corrosion area contains a lot of corrosion products on macroscopical analysis. A lot of critical corrosion pits are located in the lower part of the pipe and the maximum corrosion depth reaches 3.5 mm. The pipeline surface was covered with loose corrosion products under the electron microscope. They contained lots of Cl, C, O and Fe elements by EDAX analysis. Conclusion Material performance is not the main cause of failure accidents. The main cause of oil pipeline leakage is corrosion perforation. The main factor of corrosion perforation lies in the high Cl? fluid. When Fe from matrix is constantly dissolved and migrated by Cl? fluid, the corrosion pits will develop rapidly and lead to corrosion perforation eventually.