INSPECTING TOOL AND ITS USING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an inspecting tool adaptable to a relatively large-diameter underground pile buried in the ground and capable of detecting the corrosion occurring on its peripheral section relatively simply and to detect the corrosion of the underground pile in no contact. SOLUTION: This inspecting tool 20 is provided with a plurality of local coils 21 around a support tool shaft extending in the longitudinal direction, and each local coil 21 has a coil shaft parallel with the support tool shaft. A first connecting circuit 23 connecting all local coils 21 in series is provided between two detection ends of the ground and an output terminal.