Spiral conveyor, commonly known as twisted dragon, uses rotating spiral blades to push materials and transport them in a spiral conveyor. The force that the material does not rotate with the blades of the screw conveyor is the weight of the material itself and the frictional resistance of the screw conveyor shell to the material. The spiral blades welded on the rotating shaft of the screw conveyor have different surface types according to the conveyed materials, such as solid surface, belt surface, and blade surface. 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 with the material. When the machine length is long, a middle hanging bearing should be added. It is a widely used conveying equipment in the mineral, feed, grain and oil, and construction industries. It is made of steel and is used to transport chemical and building materials products such as powders or solid particles at high temperatures.

The tensioning device of the screw conveyor is composed of bearings, screws, nuts, and guides. Rotating the spider can move the bearing along the guide rail, and the screw should not be fixed on the bearing seat. The screw can work under compression or under tension (it works better under tension). The latter has a much longer gap in length compared to the former. Using a spiral tensioning container, the tension of the rubber belt changes during operation. As the rubber belt elongates, the tension gradually decreases. Therefore, regular gun inspections and adjustments are necessary. Due to the difficulty of manual adjustment, it is inevitable that the initial tension will become too large or too small. So it can only be applied in simple and relatively short belt conveyors like the wheels used on unloading and loading machines.

The diameter of the driving roller of a belt screw conveyor is generally larger than the diameter of the tensioning roller. The reason for this selection is that the tension changes of the incoming and outgoing branches of the rubber belt on the driving drum are relatively large. If the drum diameter is larger, the corresponding length of the drum circumference is also smaller. This way, during the transition from the incoming edge to the outgoing edge of the rubber belt, the deformation per unit length is smaller, which is conducive to improving the service life of the rubber belt.

The belt conveyor on the unloading machine usually has low power and low humidity, so a smooth surface roller can meet the sawing needs of work. In wet environments with high power and easy slipping, a rubber surface roller should be used. The potassium rubber roller has good health and quality, with a thick and wear-resistant adhesive layer. If production conditions permit, this type of roller should be selected as much as possible. Although the rubber drum has a short service life, it is easy to maintain and repair.