If the steel casing on underground gas pipelines is not properly installed,it will affect the cathodic protection potential of the steel pipeline inside the casing and then it will lead to the failure of cathodic protection of the main pipeline inside the casing.According to the actual corrosion detection cases,the influencing factors of the main pipeline corrosion inside the casing are analyzed.The main reasons are open circuit shielding and short circuit shielding effect caused by the steel casing.At the same time,the reformation measures are given by filling conductive media in the casing,installing magnesium anode winding tape on the main pipeline inside the casing,installing a protective potential detection device on the main pipeline inside the casing and others.The actual application results indicate that no electrochemical corrosion was found on the main pipeline inside the casing during the 1 year operation period after the renovation.
关键词
钢质套管/埋地燃气管道/阴极保护电位/电流屏蔽
Key words
steel casing/underground gas pipeline/cathodic protection potential/current shielding