| 摘要 |
PURPOSE:To perform flaw detection with high accuracy and to quantitatively grasp the defect state of a welded part, by analyzing the permeation of ultrasonic waves with respect to the welded part from a predetermined direction after measuring and storing the same. CONSTITUTION:The permeation of ultrasonic waves is continuously measured and stored in the direction crossing the longitudinal direction of a welded part 2 in the vicinity of the welded part 2 while the permeation of ultrasonic waves traversing the welded part 2 in the direction crossing the longitudinal direction of said welded part 2 is continuously measured and stored. Three kinds of thus obtained db-values T, B, W are inputted to an operation treatment apparatus and the arithmatic average value of the db-values T, B and the deviation with the db-value W are continuously calculated over the longitudinal direction of the welded part 2. Subsequently, the defect state of the welded part 2 is judged on the basis of the change state of said deviation in the longitudinal direction of the welded part 2. By this method, flaw detection with high accuracy is performed while the defect state of the welded part can be quantitatively grasped. |
