某油田注汽站的高温高压注汽管线在运行时发生断裂。通过化学成分分析、力学性能测试和金相检验等方法对注汽管线断裂原因进行了分析。结果表明: 管线断裂起源于管表面受到的机械损伤, 导致其断裂的原因是注汽管线经长期运行管壁受氧化腐蚀显著减薄, 且外管壁腐蚀层下出现微裂纹及孔洞, 其性能指标已不能满足技术要求, 管线在两者的共同作用下发生了断裂。

A high temperature and high pressure steam injection pipe was fractured in the run-time in a oil field steam injection station. The fracture causes of the steam injection pipe were analyzed by means of chemical composition analysis, mechanical property testing, metallographic examination and so on.The results showed that the fracture initiated in mechanical damage on pipeline surface; the fracture cause was that the wall of pipeline was thinned by oxidation corrosion after a long run; furthermore, the microcracks and holes had occurred in the corrosion layer of outer wall, these led to the performance of pipeline can not meet the technical requirement, under the action of the two factors, the pipeline was fractured at last.