Spiral Conveyor; Application scope and characteristics, structural features:

1、 Selection of Spiral Conveyor

（1） Application scope and characteristics

(1) Spiral conveyor is a widely used conveying equipment in chemical, building materials, grain and other sectors, mainly used for conveying powdery, granular and small block materials. It is not suitable for conveying materials that are prone to deterioration, viscosity, and clumping.

(2) The environmental temperature for the use of screw conveyors is -20~50 ℃; The inclination angle of the conveyor is β ≤ 20 °; The conveying length is generally less than 40m and not more than 70m.

(3) Compared with other conveying equipment, screw conveyors have the advantages of simple structure, small cross-sectional size, good sealing performance, the ability to load and unload materials at multiple points in the middle, easy operation, and low manufacturing cost. Its disadvantages are severe wear and tear of mechanical parts, low conveying capacity, high power consumption, and easy breakage of materials during transportation.

（2） Classification and structural features

(1) There are three types of spiral blades for screw conveyors: solid spiral surface type, belt spiral surface type, and blade spiral surface type. The solid spiral surface is called the s-method, and its spiral pitch GX type is 0.8 times the blade diameter. The LS type spiral conveyor is suitable for conveying powdered and granular materials. Belt type helical surface, also known as D method, has a helical pitch equal to the diameter of the helical blades, and is suitable for conveying powdered and small materials. The blade type helical surface is rarely used and is mainly used for conveying materials with high viscosity and compressibility. During the conveying process, it completes mixing and other processes simultaneously, and its helical pitch is about 1.2 times the diameter of the helical blade.

(2) The spiral blades of a screw conveyor have two directions of rotation: left-handed and right-handed.

(3) The types of screw conveyors include horizontal fixed screw conveyors and vertical screw conveyors. Horizontal fixed screw conveyor is a commonly used type. Vertical spiral conveyor is used for short distance material lifting, with a conveying height generally not exceeding 8m. The spiral blades are solid surface type, and it has horizontal spiral feeding and feeding pressure.

(4) The material outlet end of LS and GX spiral conveyors should be equipped with 1/2 to 1 circle of reverse spiral blades to prevent powder from blocking the end.

(5) The screw conveyor consists of three parts: the screw machine body, the inlet and outlet, and the driving device.

The main body of the screw machine consists of a head bearing, a tail bearing, a suspension bearing, a screw, a casing, a cover plate, and a base.

The driving device consists of an electric motor, a reducer, a coupling, and a base.