| 摘要 |
PURPOSE:To remove generated air bubbles, by obstructing a water layer rotating along the surface of the circumference of a material to be inspected, by a suitable place, when the material to be inspected is rotated at a high speed. CONSTITUTION:A material to be inspected 1 is fed into a water tank 2 filled with water 5, rotating at a high speed so that only its lower part is immersed into water. A probe 3 placed on the lower part of the water tank 2 sends and receives an ultrasonic signal as to the material to be inspected 1, and detects a flaw extending of the whole surface and the overall length. Also, when detecting a flaw, through the medium of propagation of the ultrasonic signal, the water 5 is led into a space 4 between the probe 3 and the material to be inspected 1, from the outside in a state that the probe 3 has been immersed into water. The water 5 rises in the direction as indicated with an arrow along the surface of the circumference of the material to be inspected 1, and on the rise part of a formed water layer 6', a drain water piece 8 is project-provided. The water layer 6' is obstructed by the drain water piece 8, a rotating water is scarcely formed, no air bubble is mixed into the water immersed part, and no influence is exerted on the ultrasonic signal. |
