| 摘要 |
PURPOSE:To perform ultrasonic flaw detection which high flaw detection accuracy, has no need for removing wheels, offers considerable saving in the number of inspection steps, and is free from overlooking in flaw detection by making a ultrasonic wave incident from the inside circumferential face side of a hollow wheel shaft. CONSTITUTION:An outside cylinder 1, an inside cylinder 2, mounting arms 7, and an opening and closing arm 8 are connected, and if the cylinder 1 and the cylinder 2 are relatively moved in an axial length direction by an opening and closing handle 6, the respective arms 7 are rotated and probes 41, 42 and a dummy 43 centrifugally space each other with respect to the axial centerline of the cylinder 1, whereby they are attached or detached to or from the inside circumferential surface of hollow wheel shaft. The respective probes 41-43 are spirally moved with respect to the inside circumferential surface of the hollow wheel shaft by the rotating motion around the axial centerlines of the cylinder 1 and the cylinder 2 and their movement in the axial length direction by a rotary handle 5, whereby the contact positions can be properly changed. A dummy 43 is made of plastics or the like and is formed in their outside shape into an approximately circular shape in one piece with the probes 41, 42. Shoes 41b-43b opposite to the inside circumferential surface of the hollow wheel shaft are all formed into a circumferential surface of a convex arc. |
