| 摘要 |
PROBLEM TO BE SOLVED: To obtain ultrasonic inspection method and inspection apparatus for L-shaped joint in which a defect in the vicinity of welded part can be detected with high accuracy. SOLUTION: A longitudinal wave flaw detection probe 1 mounted on the side face 41a of a plate member 51 not to be inspected is combined with a transverse wave flaw detection probe 2 mounted on the lower surface 52a of a plate member 52 to be inspected. At first, the probe 1 on the side face 51a determines presence and position of a flaw 3 through a welded part 5. When a flaw 3 is present, the gain of a receiver is increased and then the probe 2 on the lower surface 52a detects an echo from the end part defect 3. Subsequently, the probe 1 scans on the plate member 51 and the intensity distribution of echo is determined. Finally, the receiving positions x1 , x2 of maximum end echo and maximum defect corner echo are determined and the difference is operated at an operating section thus sizing the defect. |
