Screw Conveyor

Screw Conveyor (Auger Conveyor)

The Versatile, Enclosed Solution for Metered Transfer of Powders and Granules

The Screw Conveyor, or Auger Conveyor, is a simple, reliable, and highly adaptable mechanical conveyor used to move bulk materials horizontally, on an incline, or vertically. It consists of a helical screw (flight) rotating within a stationary trough or tube. As the screw turns, it pushes material along the trough. Its enclosed design makes it ideal for dusty, fine, or semi-fluid materials, and it excels in applications requiring metered feeding, blending during transport, or operation in tight spaces where other conveyors cannot fit.

Screw Conveyor

Key Features

  • Helical Screw (Flighting)

    The core moving part, available in various designs (standard, cut-flight, ribbon) to handle different material characteristics from free-flowing to sticky.

  • Enclosed Trough or Tube

    Contains the material and screw, preventing spillage, protecting the product from contamination, and minimizing dust emission.

  • Modular & Flexible Layout

    Can be configured in straight sections, curved sections (with special hanger bearings), and varying inclinations to navigate around equipment and obstacles.

  • Multiple Inlet & Outlet Options

    Can be equipped with numerous feed inlets and discharge gates along its length for complex distribution or collection systems.

  • Simple Drive & Support

    Typically driven by an electric motor and gear reducer at the discharge end, with intermediate hanger bearings for long conveyors.

Advantages

  • Excellent Dust Containment

    Fully enclosed design is perfect for handling fine powders (like phosphate dust, lime) and preventing product loss or environmental contamination.

  • Metering & Feeding Capability

    Provides a consistent, controllable flow rate, making it ideal as a feeder to weigh scales, mixers, or packaging machines.

  • Compact Design & Low Headroom

    Requires less space than belt or drag chain conveyors, allowing installation in cramped areas, under hoppers, or as part of machine integration.

  • Can Handle a Range of Materials

    With appropriate flighting design, it can convey materials from fine powders to small granules and even semi-solid pastes.

  • Low Initial Cost & Maintenance

    Simple mechanical design with few components leads to affordable installation and easy maintenance.

Applicable Raw Materials

  • Fine Powders

    Cement, fly ash, lime, powdered fertilizers, filter dust.

  • Granular Materials

    Fertilizer granules, seeds, grains, plastic pellets.

  • Semi-Solid Materials

    Dewatered sludge, moist by-products (with suitable flight design).

Basic Structure & Components

Screw Conveyor
Trough or Tube

U-shaped (for easy access) or cylindrical (for full containment), usually made of carbon or stainless steel.

Screw Flight (Auger)

A helical blade welded to a central pipe (shaft). The pitch and diameter determine capacity.

Drive Unit

Electric motor, gear reducer, and drive shaft connection.

End Bearings

Support the screw shaft at the drive and opposite ends.

Intermediate Hanger Bearings

For long conveyors, these support the screw shaft at intervals but can create a potential wear point for the material.

Inlet & Outlet Openings

Flanged connections or openings for material entry and exit.

Cover

A removable cover for the trough to allow access for inspection and cleaning.

Technical Data

Screw diameter (mm)

100

160

200

250

315

400

500

630

800

1000

1250

Screw pitch (mm)

100

160

200

250

315

355

400

450

500

560

630

Rotation speed (r/min)

140

112

100

90

80

71

63

50

40

32

25

Conveying capacity (m³/h)

2.2

8

14

24

34

64

100

145

208

300

388

Rotation speed (r/min)

112

90

80

71

63

56

50

40

32

25

20

Conveying capacity (m³/h)

1.7

7

12

20

26

52

80

116

165

230

320

Rotation speed (r/min)

90

71

63

56

50

45

40

32

25

20

16

Conveying capacity (m³/h)

1.4

6

10

16

21

41

64

94

130

180

260

Rotation speed (r/min)

71

50

50

45

40

36

32

25

20

16

13

Conveying capacity (m³/h)

1.1

4

7

13

16

34

52

80

110

150

200

Note: Due to different material filling factors, the capacity may vary. The capacity may also change depending on the material’s viscosity and the conveying angle.

 

Key Differentiators vs. Other Conveyors

Better for dusty materials, metering, and tight spaces, but has higher power consumption per meter and more wear for abrasive materials. Not suitable for very long distances or heavy, lumpy materials.

Both are enclosed. Screw conveyors are simpler, less expensive, and better for powders and gentle inclines. Drag chains are better for longer distances, higher capacities, and handling more abrasive materials without the intermediate bearings that can cause issues in screw conveyors.

Screw conveyors are a low-energy, mechanical solution ideal for shorter distances and defined paths. Pneumatic systems offer greater layout flexibility but have much higher energy costs and are for lower capacities of lighter materials.

A screw conveyor can be configured vertically as a “screw elevator,” but it is only suitable for short lifts with non-abrasive, free-flowing materials. Bucket elevators are far more efficient and standard for dedicated vertical lifting.

It is the go-to, cost-effective workhorse for controlled, enclosed transfer of powders and granules over short to medium distances within a processing plant, especially where space is limited or dust control is paramount.