西部某压气站压缩机出口埋地管线外腐蚀原因分析

为了分析西部某压气站压缩机出口钢级为L415的埋地管线外腐蚀原因，对该管段进行了宏观检查、壁厚测量、理化检验、扫描电镜（SEM）、X射线衍射物相以及土壤等综合分析。结果表明，该段管线外腐蚀的直接原因为防腐层失效，钢管失去保护，裸露于外部环境，同时土壤中Cl-含量较高，易造成管体腐蚀，管道温度变化及管体与混凝土基座接触是腐蚀加速的间接原因。

Cause Analysis of Compressor Outlet Buried Pipeline External Corrosion in a Western Compressor Station

In order to analyze the cause of external corrosion of buried pipeline of L415 steel grade compressor outlet of a compressor station in western, appearance inspection，wall thickness measurement, physical and chemical inspection, scanning electron microscopy（SEM）, X-ray diffraction analysis and soil analysis were used for the pipeline. The results showed that the direct cause of the external corrosion was the failure of the anti-corrosion layer, the steel pipe lost its protection and exposed to the external environment. At the same time, the content of Cl- in soil was high, which was easy to cause pipe corrosion, and the he change of pipe temperature and the contact between pipe body and concrete plinth were the indirect cause of corrosion acceleration.