First, the selection of screw conveyor

(I) Application scope and characteristics
(1) Screw conveyor [1] is a kind of conveying equipment widely used in chemical, building materials, food and other sectors, mainly used for conveying powdery, granular and small block materials. It is not suitable for conveying perishable, sticky and lumpy materials.
(2) The ambient temperature used by the screw conveyor is -20 ~ 50 ℃; the inclination angle of the conveyor β≤20 °; the conveying length is generally less than 40m and the longest does not exceed 70m.
(3) Compared with other conveying equipment, screw conveying has the advantages of simple structure, small cross-sectional size, good sealing performance, multi-point loading and unloading, safe and convenient operation, and low manufacturing cost. Its disadvantages are severe wear of the parts, low conveying capacity, high power consumption, and the material is easily broken during transportation.
(B) classification and structural characteristics
(1) The spiral blades of the screw conveyor have three types: solid spiral surface type, belt spiral surface type and blade spiral surface type. The solid spiral surface is called the s manufacturing method, and its spiral pitch GX type is 0.8 times the blade diameter. The LS type screw conveyor is suitable for conveying powdery and granular materials. The belt spiral surface is also called D manufacturing method. Its spiral pitch is the same as the diameter of the spiral blade. It is suitable for conveying powdery and small pieces of material. The blade type spiral surface has fewer applications, and is mainly used for conveying materials with high viscosity and compressibility. During the conveying process, the processes of stirring and mixing are completed at the same time.
(2) The spiral blades of the screw conveyor have leftward and rightward rotations.
(3) The types of screw conveyors are horizontal fixed screw conveyors and vertical screw conveyors. Horizontal fixed screw conveyor is the most commonly used type. The vertical screw conveyor is used to lift materials over a short distance. The conveying height is generally not greater than 8m. The spiral blade is a solid surface type. It must have a horizontal spiral feeding to ensure the necessary feeding pressure.
(4) LS, GX type screw conveyor material outlet end should be provided with 1/2 ~ 1 turn reverse spiral blade to prevent powder from blocking the end.
(5) The screw conveyor consists of the screw machine body, the inlet and outlet, and the driving device.
The screw machine body is composed of a head bearing, a tail bearing, a suspension bearing, a screw, a casing, a cover plate and a base.
The driving device is composed of a motor, a reducer, a coupling and a base.
The danger of conveyor belt deviation
The belt deviation is extremely harmful to the production process. From the actual operation situation, the impact of the belt deviation on the belt conveyor operation and production mainly has the following aspects: Triggering the emergency stop device. An emergency stop contact switch is installed on the belt conveyor for protection. When the side of the belt contacts the emergency stop switch, it will stop the transportation operation, affect the operation efficiency of the entire production line, increase production costs, and may cause the plan to be completed in time if it is serious. And even cause bad contract disputes.
 
Reduce the life of some major components. The first is the failure of mechanical moving parts such as rollers and bearings. The deviation of the belt increases the axial force on the roller and the idler, which increases the probability of failure. The second is the excessive wear of the belt. The deviation of the belt causes the material to fall on the return belt. In the case that the return belt cleaner cannot completely remove the material, it causes abnormal wear of the belt and the roller rubber, reducing the life of the roller rubber and the belt; the third is that the belt tears from the edge, and the belt The friction of the bracket for a long time can cause severe wear of the belt edges, affect the belt life, increase maintenance costs and operating costs. When the belt runs badly, it will directly cause the belt to tear. A serious deviation of the belt may cause the belt to roll over, resulting in a sudden increase in force on one side of the belt, which may cause the belt to break laterally.