Study on Corrosion of Buried Metal Pipeline by Stray Current Along Metro Line

: This year, with the continuous improvement of China's subway system, serious corrosion problems of metal buried pipelines laid along the subway have attracted social attention. In order to discuss the corrosion mechanism, this paper briefly describes the corrosion status and characteristics of the subway stray current on the buried metal pipes, and introduces the characteristics of the subway stray current on the buried metal pipes, such as fast corrosion speed, large strength and wide influence range. The corresponding corrosion mechanism is summarized, and the detection and protection methods of stray current at home and abroad are introduced. Including pipe to ground potential test, soil potential gradient test, test piece method or polarization probe method test, current probe method test, intelligent stray current detector (SCM) test, corrosion inspection piece test, etc. The protection method of "giving priority to plugging, taking drainage as auxiliary, combining plugging with drainage, and strengthening monitoring" is proposed.