COATING DAMAGE DETECTION METHOD OF BURIED METAL PIPE

摘要

PROBLEM TO BE SOLVED: To provide a technology capable of detecting accurately a coating damage of a buried metal pipe, by fully removing the influence of stray current passing through the buried metal pipe.;SOLUTION: In this coating damage detection method of the buried metal pipe 1, an electrical signal is supplied to the buried metal pipe 1 made of a metal and buried underground G, and a coating 2 damage of the buried metal pipe 1 between two spots is detected from at least either value of potentials and current values of the two spots on the buried metal pipe 1. In the method, electriccal terminal side of the buried metal pipe 1 is grounded via an impedance element 32.;COPYRIGHT: (C)2006,JPO&NCIPI