DETECTION METHOD OF FRONT LAYER DEFECT OF SOLID FRONT LAYER SURFACE BY ULTRASONIC WAVE

摘要

PURPOSE:To detect easily a front layer defect from an outside by making incident an ultrasonic wave from the outside surface of the solid toward the inside detection surface for detecting the front layer defect and displaying an F echo at the detection surface on the CRT of an A scope. CONSTITUTION:The ultrasonic wave is made incident at an intrinsic directional angle theta toward an inside peripheral surface 1b, a rolling surface S and a grease groove 1c by a normal probe 5 placed on an outside peripheral surface 1a. A pulse reflection type ultrasonic flaw detector 6 is connected by a high-frequency cable 7 to the probe 5. The CRT6a of the A scope display taking the reception input supplied from the probe 5 at the axis of ordinate and the propagation time of the ultrasonic wave at the axis of abscissa is provided. The F echoes appear on the CRT6a by as much as the number of flaking if the flaking exists.