Spiral conveyor is a mechanical device that uses an electric motor to drive a spiral to rotate and push materials to achieve the purpose of conveying. It can be transported horizontally, obliquely or vertically, with the advantages of simple structure, small cross-sectional area, good sealing, easy operation, easy maintenance, and convenient enclosed transportation. Spiral conveyors are divided into two types in terms of conveying form: axial spiral conveyors and shaftless spiral conveyors. They are also divided into U-shaped spiral conveyors and tubular spiral conveyors in terms of appearance. Axial screw conveyor is suitable for non viscous dry powder materials and small particle materials (For example: cement, fly ash, lime, grain, etc.) and shaftless screw conveyors are suitable for conveying materials that are viscous and easily entangled. The working principle of a screw conveyor (such as sludge, biomass, garbage, etc.) is that the rotating spiral blades push the material and transport it. The force that prevents the material from rotating together with the spiral conveyor blades is the weight of the material itself and the frictional resistance of the screw conveyor housing to the material.
The spiral blades welded on the rotating shaft of the screw conveyor have different surface types depending on the conveyed material, including solid surface type, belt surface type, and blade surface type. The screw shaft of the screw conveyor has a thrust bearing at the end of the material movement direction to provide axial reaction force to the screw along with the material. When the machine is long, an intermediate suspension bearing should be added.
