Bulk flow and throughput measurement
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Radiometric belt scales measure the area weight of a product. With an external input for speed (or constant speed) these systems provide an online mass flow reading. They can be easily used for all kinds of conveyors, making them the system of choice for reliable and reproducible results. They are perfectly suited for monitoring loading- and unloading procedures, material mixing, or dosing applications. Environmental influences such as dust, wind, vibration, or fluctuation in conveyor belt tension do not affect the measurement at all. In contrast to mechanical solutions the radiometric system does not need maintenance or frequent recalibration. Radiometric belt scales can be easily retrofitted without costly modifications to any existing conveying systems (e. g. conveyor belt, screw conveyor or box conveyor).
Different radiometric setups are possible: a cost-effective solution is represented by a Cs-137 point source and a rod detector. This solution is ideal for materials with low bulk density and small loading height. For chain conveyors or conveyors with a wide belt width two Cs-137 point sources in combination with a rod detector are favored. However, the best accuracy and best measurement stability are provided by the arrangement of a Co-60 rod source in combination with a point detector. Due to the higher gamma energy, Co-60 delivers a higher penetration depth, which makes this arrangement the superior solution for higher bulk loads and very dense materials. For each of the options addressed, detector(s) and source(s) are mounted to a measuring frame, which is adjusted in size and orientation to the conveyor.