Choonpatanshohohotosonopuroobu

摘要

PURPOSE:To detect a vertical cracking defect at a high speed without lowering flaw detection precision by arranging only one or two adjacent converters at a distance of one skip from a part to be inspected. CONSTITUTION:Converters 15-18 form the 1st group and converters 19-22 form the 2nd group. Further, the 1st and the 2nd groups cover flaw detection areas I and II. In this case, the converters 17 and 18 in the 1st group and the converters 21 and 22 in the 2nd group are arranged at a distance of one skip from their original positions. When ultrasonic flaw detection is performed by the 1st and the 2nd groups, the transmitting/receiving operation of the converter 15 is performed by the 1st group and then operations of the converters 16-18 are carried out, and flaw detection is performed by a 1-probe method and then flaw detection is performed by a 2-probe method. Thus, the flaw detection is completed and flaw detection by the 2nd group is performed, thus finishing one period of flaw detecting operation.