METHOD FOR JUDGING HARMFUL DEFECT IN ULTRASONIC FLAW DETECTION, AND METHOD FOR UTILIZING ITS JUDGMENT RESULT

PROBLEM TO BE SOLVED: To provide a harmful defect-judgment method in ultrasonic flaw detection for easily judging whether a defect is a harmful one or not. SOLUTION: In an ultrasonic flaw detection apparatus for performing both angle beam flaw detection and vertical flaw detection, the strength of reflection echoes from a defect is measured by the angle beam flaw detection for the same site of a steep pipe that is a material to be inspected, and at the same time one of the thickness of the material to be inspected and the reflection echo strength from the surface is measured by the vertical flaw detection, and it is judged that a harmful defect is present in the site when a measurement value by the angle beam flaw detection exceeds a specific threshold, and at the same time a measurement value by the vertical flaw detection exceeds a specific threshold. COPYRIGHT: (C)2003,JPO