| 摘要 |
PURPOSE: To correctly detect a height of an axial center of an axle so as to correctly register a probe in height set at an end face of the axle when a flaw is to be detected by ultrasonic waves with the use of the probe highly accurately. CONSTITUTION: A flange part A1 not abraded in a wheel A is supported by a roller 12 in a freely rotatable manner. A sensor 27 is set to an elevator body 20. The elevator body 20 is lowered until the sensor 27 hits an upper face of an end part, B1 of an axle B. A lowering distance L1 of the elevator body 20 is added to a radius R0 of the end part B1 of the axle B, and a heightwise difference L2 from an origin (an upper limit position) of the elevator body 20 to an axial center B2 of the axle B is operated. The up/down movement of the elevator body 20 is controlled based on the difference L2. |
