埋地管道钢制套管内杂散电流腐蚀穿孔机理研究

摘要

In the practice of oilfield pipeline construction, limited by along geographical distribution, some parts of the pipeline are used protective steel casing when crossing the roads, canals, rivers, etc. However, this will affect the distribution of cathodic protection current and potential, so that those sections of pipeline will become the weak points in cathodic protection system. Based on the analysis of cathodic protection of steel casing and shielding stray current corrosion damage of pipeline, the corrosion perforation mechanism of the pipeline within the protective casing was studied, and design requirements for the pipeline within the protective casing, and detection, prediction and control measures of alternating current corrosion were proposed.%在油田管道施工实践中，受沿线地理位置分布的限制，部分管段在穿越道路、沟渠、河流等处采用了钢制套管防护，但这将影响阴极保护电流和电位的分布，从而使该管段成为管道阴极保护系统的薄弱环节。基于对输油管道钢制套管阴极保护屏蔽及杂散电流腐蚀破坏分析，研究了套管防护内管段腐蚀穿孔机理，提出了套管防护管段设计要求及交流腐蚀检测、预测和控制措施。