METHOD OF IDENTIFYING REAR BEAD ECHO DURING ULTRASONIC FLAW DETECTION OF WELDED PART

摘要

PROBLEM TO BE SOLVED: To enable automatic identification of an echo attributed to an actual defect in a welded part from an echo attributed to a rear bead within an ultrasonic flaw detection apparatus. ;SOLUTION: An angle θ of refraction corresponding to an echo from a position where the echo returns easily at a rear bead of a welded part is computed and a beam course WB of the echo from the rear bead is computed based on the angle θ of refraction computed. A ratio is computed between the beam course WB of an echo with a reflection source unknown caught by an ultrasonic flaw detector and the beam course WB at the position where the echo returns easily. Thus, a fuzzy reasoning is performed about the possibility that a echo from the rear bead may be found using a fuzzy rule based on the beam course ratio obtained and the angle of refraction corresponding to the echo from the rear bead.;COPYRIGHT: (C)1997,JPO