Working Principle, Structure and Application of Screw Conveyor

Screw conveyor is a continuous conveying machine with no flexible traction components.

 

 

1. Structure

The main components of the screw conveyor used to transport bulk materials in the horizontal and slightly oblique directions are: a semi-circular trough and a spiral mounted on a suspension bearing arranged in it. The drive device drives the spiral to rotate, and the material passes. The hopper is loaded into the trough, and the material is discharged at the middle discharge port.

 

A vertical screw conveyor used to transport bulk materials in a vertical direction. The screw is hung on the top bearing, and the lower part is centered by a self-aligning ball bearing. The trough of the feeding section is a conical tube, and the rest is a cylindrical tube. The driving device drives the spiral to rotate, and the material is fed from the bottom to the top and discharged.

 

2. Working Principle

The working principle of the screw conveyor is: the screw rotates in a closed trough, so that the material loaded into the trough is heavy due to its own weight.

 

The force and its effect on the frictional force of the trough, instead of rotating with the screw, only move forward along the trough; in the vertical screw conveyor, the material moves upwards by centrifugal force and the frictional force on the trough wall of.

 

3. Features

The main advantages of screw conveyors:

1) The structure is relatively simple, compact, easy to manage and operate;

2) The work can be tested, the maintenance is not too complicated, and the cost is low;

3) Because the material trough is closed, it is convenient to transport dusty, hot (200℃) and strong odor materials, reduce environmental pollution and improve working conditions;

4) It can easily realize multi-point feeding and multi-point unloading;

5) A conveyor can convey materials in two directions at the same time, that is, towards the center or away from the center;

6) During the conveying process, it can be combined with the mixing, stirring or cooling process;

7) The rigidity of the trough is relatively large, so it can withstand a certain bending moment well.

 

The main disadvantages of the screw conveyor are: due to the agitation of the screw conveying the material and the friction of the material on the screw and the material, the running resistance and power consumption are large, the parts are worn out, and the maintenance workload is large. At the same time, it is more sensitive to overload. Prone to blockage.

 

 

4. Application

Because of the above reasons, screw conveyors are widely used in industrial fields such as building materials, food, chemistry, machinery manufacturing, and transportation to transport cement, coal powder, ore, flour and other materials. The inclination angle of the screw conveyor used for horizontal and slightly inclined conveying is less than 20°.

 

When arranging a conveyor, if possible, it is best to arrange the driving device at the discharge end, so that the screw is in a favorable state of tension. At the same time, care should be taken not to arrange the support base or the discharge port on the housing joint. At the flange, the inlet should not be arranged at the cover joint and above the suspension bearing.