| 摘要 |
PURPOSE:To shorten working time, by mounting a deformable member, on the outer surface side of a delay material, which is mounted on one surface of a vibrator, providing a medium oil in the contact surface between the delay material and the deformable member, and detecting a defective part, whose slant angle with respect to a flaw detecting surface is different. CONSTITUTION:A spherical--surface shaped delay material 7 is bonded to a vibrator 6. A circular cylinder part is provided at the tip of the main body of a flaw detector including both vibrator and delay material. An annular oil well 8 is formed at the circular cylinder part. A soft rubber body 9 is closely coupled with the material 7. To a contact surface 10 between the soft rubber body 9 and the delay material 7, a medium oil is supplied from the oil well 8. The rubber body 9 and the delay material 7 are closely contacted through the medium oil. The optimum distance from the contact surface of the rubber body 9 and the delay material 7 to the tip surface of the circular cylinder part, i.e., the thickness of the soft rubber, is about 3mm, based on the tenon angle of a steam turbine and relationship between a crack angle determined by experience and the thickness of the soft rubber. |
