Abstract: 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 any ultrasound 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. With proper frequency selection, ultrasound can be transmitted a surprising distance through conveyor belting made of rubber-like material.

Abstract: Apparatus for measuring the bulk density and mass flow rate of pulverized coal entrained in air along a duct 6 comprises beta radiation source means 7, radiation detection means 8 and a shield 9 to intercept direct radiation falling on the detector means which thereby measures the diffuse radiation scattered by the coal particles. That measurement plus a signal indicating linear coal particle speed is fed to a data processor which calculates the bulk density and mass flow rate.