某油田天然气输送管线泄漏原因分析  

Cause Analysis of Natural Gas Pipeline Leakage in the Oilfield

作　　者：赵向东[1] ZHAO Xiangdong(Sichuan Oil and Gas Construction Engineering Co.,Ltd.,Chengdu 610051,China)

机构地区：[1]四川石油天然气建设工程有限责任公司,成都610051

出　　处：《焊管》2020年第7期25-29,共5页Welded Pipe and Tube

摘　　要：某油田天然气输送管线在半年内连续4次发生泄漏,给管线的正常运行带来极大的安全隐患。为了找到管道发生泄漏的原因,截取了部分泄漏管段,对其进行了宏观形貌、理化性能、扫描电镜、能谱分析及X射线衍射等分析研究。结果表明:该输送管道的材质满足GB/T 9711.2—1999对L245MB焊接钢管的要求;管道内壁的腐蚀机理为CO2和H2S腐蚀;发生泄漏的主要原因是管道内外的温度差导致管内水蒸气凝结于管底形成液态水,与管道内腐蚀性气体CO2和H2S共同作用,导致管壁腐蚀减薄直至发生刺漏。The natural gas transmission pipeline in an oil field leaks four times in half a year,which brings great safety risks to the normal operation of the pipeline.In order to find out the causes of the leakage,some leaking pipe sections were cut off,and their macromorphology,physical and chemical properties,scanning electron microscopy,energy spectrum analysis and X-ray diffraction were studied.The results show that the material of the pipeline meets the requirements of GB/T 9711.2—1999 for L245MB welded steel pipe.The corrosion mechanism of pipeline inner wall is CO2 and H2S corrosion.The main reason for the leakage is that the temperature difference inside and outside the pipe causes the water vapor in the pipe to condense at the bottom of the pipe to form liquid water,which works together with the corrosive gases CO2 and H2S in the pipe,leading to the corrosion thinning of the pipe wall until the leakage occurs.

关 键 词：油气输送管道 腐蚀 泄漏 CO2腐蚀 H2S腐蚀 

分 类 号：TE988.2[石油与天然气工程—石油机械设备]