Air Supported Belt Conveyors
Functional Description (refer to figures below)
An air-supported conveyor comprises an endless rubber belt (a) supported between its head (b) and tail (c) pulleys by a cushion of air on the carrying-side (d) and idlers on the return-side (e).
Material (f) is loaded onto the conveyor at the tail-end via a chute (g) and is transported along the carrying-side to the head-end where it discharges into a discharge chute (h) which guides the product onto the downstream equipment.
The conveyor belt is usually driven by means of the head pulley and the tension in the belt is maintained by means of a gravity take-up unit or a screw take-up (i).
The troughed shape of the carrying-side belt is achieved by means of the form of the steel trough plate (j) beneath the belt, which is an integral part of the air-tight plenum chamber (k).
Air is introduced into the plenum chamber by means of a low pressure centrifugal fan (l) and exits the plenum chamber via a series of holes (m) in the troughed steel plate beneath the carrying belt. It is this 'pressurised' air which floats the belt above the plate and takes the place of troughing idlers.
The carrying belt can be enclosed in a cover (n) for dust-tight applications in which case the air is vented (o) at the head-end to atmosphere or to a filter.
Multiple loading points can be accommodated and the conveyors are most often used as plant conveyors, with lengths up to 500 m, carrying a variety of materials on conveyor belts of 2 100 mm in width.
Air-supported belt conveyors are used to convey difficult or dusty or precious products where spillage, pollution or security of the material is important.