PIPE MATERIAL DISCRIMINATION

摘要

A method of and a corresponding apparatus for determining the material from which an underground pipe (10) is made, the method comprising exposing a portion of the pipe; applying a coil means (11) having a primary winding (13) and a secondary winding (14) to the exposed portion of the pipe such that the pipe contributes to an inductive coupling between the primary winding (13) and the secondary winding (14); applying an excitation current to the primary winding to induce in the secondary winding a signal indicative of an induction value of the pipe; and determining the material from which the pipe is made dependent upon the signal induced in the secondary winding.