Flexible Screw Conveyors
Also known as a Spiral Conveyors, Screw Conveyors, helix conveyor or centerless auger conveyors, consists of a spring steel or stainless steel, flexible screw that is enclosed in a flexible or rigid plastic tube, or a rigid steel tube, and driven by an electric motor normally located at the discharge end of the Conveyors. This simple design delivers efficient performance and high reliability while reducing maintenance and cost. When properly engineered according to the specific characteristics of the material being conveyed and the process into which it will be integrated, a flexible screw conveyor can outperform rigid Screw Conveyors, bucket elevators, drag chain conveyors, aero mechanical conveyors and other equipment intended to transport powder and bulk solid materials.
The intake end of a flexible screw conveyor tube is typically equipped with a charging adapter a U-shaped trough that connects to the outlet of a hopper or directly to the outlet of process equipment such as a bulk bag discharger, bag dump station, grinder, crusher, screener, blender, reactor or storage vessel of any kind.
The flexible screw passes through the charging adapter trough, exposing a section of the screw to material flowing into the trough from above. When rotating, the exposed section of screw feeds material into the outer tube, where it is then propelled through the tube by the enclosed portion of the screw.
A phenomenon resulting from the loose fit of a rotating flexible screw within a tube filled with bulk material, is that the screw automatically self-centers within the tube, providing clearance between the screw and tube wall. This affords sufficient space for particles to flow without damage, depending on the fragility and size of particles being conveyed. A removable clean-out cap covers the intake end of the conveyor tube, permitting rapid emptying and flushing of the tube, as well as disassembly and wash-down of components. Because the intake end of the screw requires no bearing, and since the discharge end is coupled to the motor drive above and/or beyond the point at which material exits the discharge spout, material does not come in contact with seals or bearings. The flexible screw is therefore the only moving part contacting material.