PARASITE CURRENT TEST METHOD AND PARASITE CURRENT TEST APPARATUS

摘要

eddy current testing method and eddy current testing apparatus. in a eddy current test method that involves the use of a rotary eddy current test probe where a sensing coil is arranged within an exciter coil, a change in sensing sensitivity (a sensing sensitivity deviation ) which changes depending on the rotational position of the detection coil is reduced. the eddy current test probe includes an exciter coil ec1, a detection coil dc1, an exciter coil ec2, and a detection coil dc2, which are mounted on a ds disk. the eddy current probe is placed for the purpose of facing a circumferential surface of an object to be inspected, which is in the shape of a circular cylinder, and the disk ds is rotated. then, the distance (displacement) between detection coils dc1 and dc2 and an inspection surface changes. therefore, also the detection sensitivity for a fault signal changes. To reduce the change in sensing sensitivity, sensing sensitivity is adjusted by sensing the rotational position (rotational angle) of the dc1 and dc2 sensing coils.