摘要 |
<p>Flaws may be detected in conveyor belting in motion by transmitting ultrasound to the belting at one zone, detecting ultrasound propagated by the belting from the one zone to another zone spaced apart from the first and issuing a signal responsive to ultrasound if any detected whereby a signal is obtained which is indicative of discontinuities in the belting intermediate the zones. Preferably a column of water extending between an ultrasonic transducer and the belt is used for ultrasonic coupling during motion of the belt and tracking means are provided to maintain the column at constant length.</p> |