| 摘要 |
PURPOSE:To perform accurate measurement irrespective of the surface level fluctuation of a steel plate caused by the variation or defective shape of a pass line and the variation of the inclined direction and angle of the steel plate by using a focusing type transmitter which focalizes ultrasonic beams near the surface of the steel plate as an ultrasonic transmitter and a non-focusing type receiver as an ultrasonic receiver. CONSTITUTION:Burst waves generated from a function generator 30 are supplied to a focusing ultrasonic transmitter 20 after the waves are power-amplified by means of a transmission amplifier 32. The multiple reflection echoes of the waves arriving at a steel plate 10 through a medium are received by a non-focusing ultrasonic receiver 22. Of the received signals amplified by means of a reception amplifier 40, peak voltages within a gate range are held by a gate peak detector 43 and a personal computer 44 reads and edits the output values of the detector 42. Since the focusing transmitter 20 which focalizes ultrasonic waves near the surface of the steel plate 14 is used so as to improve the surface resolution of the steel plate 10 and the non-focusing ultrasonic receiver is used so as to reduce the influence of angle variation in such a way, stable ultrasonic inspections can be performed. |
