Sensitivity correction method and sensitivity correction apparatus of eddy current flaw detection apparatus

摘要

PROBLEM TO BE SOLVED: To correct sensibility during operation of a manufacturing line with respect to a sensitivity change generated in an eddy current sensor.SOLUTION: The method for correcting sensibility of an eddy current flaw detector comprising a flaw sensor for inspecting a metal band running on a non-metal roll, includes detection steps (steps S1 and S2) for detecting a metal piece provided outside of an edge part of the metal band in the width direction, of the roll surface of the non-metal roll by using a correction sensor formed of a non-contact type eddy current sensor during operation of a manufacturing line of the metal band, a calculation step (step S3) for calculating a correction coefficient on the basis of a detection value of the metal piece obtained by the correction sensor, and a correction step (step S5) for correcting sensibility of the detection value of the metal band output from the flaw sensor with the use of the correction coefficient.SELECTED DRAWING: Figure 1