Originally vibratory disk-feeders and -reclaimers were designed with rather small diameters. they were mainly applied in chemical process plants, and were mostly flush mounted underneath bins of modest size, say up to 1 m diameter. Over the past decades they have been increasingly used for bins of much larger diameter, some via a hopper and some not. the latter may cause and unfortunate combination of the most important parameters, leading to malfunctioning and even to feeder jam. This work shows that basically vibratory disk feeders should be installed via a hopper, which for practical reasons becomes feasible above diameters of approximately 0.8 m, depending on the material to be reclaimed and the required mass flow. Feeders of considerable size, up to 2.5 m, may very well operate satisfactorily when properly mounted underneath a hopper. Nonfunctioning of vibratory disk feeders is mostly caused by a combination of too bad flowability of the bulk material to be reclaimed; too high a feeder load and wrong silo fill procedures and feeder power-up procedures.
