油田集输管道腐蚀行为分析

Corrosion Behaviour Analysis of Oil Field Gathering Pipeline

以腐蚀严重的油田集输管道为研究对象,对油田集输管道的腐蚀行为进行分析。在腐蚀严重的管道上制取实验试样,利用X-射线衍射仪测定腐蚀产物的相组成,利用扫描电子显微镜和金相显微镜观察其腐蚀孔周围组织的微观形貌。结果表明,油田集输管道内水样中存在着大量的H2S、Cl-和SO42-,引起腐蚀的主要原因是由于Cl-的存在,而H2S起到了一定的协同作用。油田集输管道腐蚀方式以点蚀为主,并伴有不同程度的均匀腐蚀,腐蚀产物主要以Fe2(SO4)3为主,还有部分Fe3O4、FeCl3和FeS。通过观察确定管道点蚀穿孔部位多在缺陷处产生,因此管道缺陷也是引起腐蚀的重要因素。

The corrosion behaviors of oil field gathering pipeline with heavy corrosion were invesitgated.By X-ray diffraction method,the phase composition of corrosion products was probed and with scanning electron microscopy and optical microscopy,the microstructure surrounding corrosion holes was investigated.The results showed that the main cause of the corrosion of pipeline is due to the presence of aqueous Cl-and H2S also plays a certain synergy effect.The dominant corrssion mode of oil field gathering pipeline is pitting corrosion accompanied by various degrees of uniform corrosion.Fe2（ SO4） 3 is the main corrosion product and small amount of Fe3O4,FeCl3,and FeS exist in the products.According to the analysis,punctures resulting from pitting corrosion mostly take place at pipe defects,so the pipeline defects is an important factor for the corrosion.