Screw Conveyors

Twin-screw conveyors
Damping screw conveyors
Mixing screw conveyors

Screw conveyors – compact bulk material conveyance with integrated process technology

Screw conveyors are used to discharge and transport nearly all bulk materials including fibrous and paste-like products. They move bulk material with a rotating, spiral conveying screw in a trough or a tube trough.
The advantages of screw conveyors are low susceptibility to failure, low costs, low space requirement and dust-free transport.

They also offer the possibility to feed and remove flexibly transported goods along the conveyor line. Various designs are available for steep inclined and vertical conveying as well as for work processes such as mixing, stirring, washing, sieving, heating and cooling.

Special specifications

Screw conveyors are available in various materials.

Trough screw conveyor

For the transport of bulk material in a closed U-shaped or box trough.

Special feature:

  • gradients of up to 30° are possible

Tube screw conveyor

For the transport of bulk material in a closed tube.

Special feature:

  • gradients of more than 30° are possible

Cooling screw conveyor

Heat exchanger for the cooling of bulk materials.

Special features:

  • continuous cooling
  • shaft and jacket (trough) cooling

Twin-screw conveyor

Discharge component for slow-flowing bulk materials, e.g. as discharge conveyor under hunkers or silos.

Special features:

  • dual or multiple shaft design
  • can be used as continuous screw conveyor

Damping screw conveyor

For the damping of powdery bulk materials during transportation.

Special features:

  • self-cleaning construction of the worm shafts
  • adjustable water supply

Mixing screw conveyor

For the mixing of one or more bulk materials during

Special features:

  • optional armouring of mixing blades or paddles
  • optional adjustable paddles

Special designs / application examples

Upon request also wear protected screw conveyors are available:
the conveying of abrading goods wears down the protection of the screw provided by build-up welding or the use of wear-resistant sheet metals such as manganese steel (1.3401). The optimal method to render screw blades wear and corrosion resistant is to apply the SCHRAGE metal spraying coating followed by thermal redensification.

Performance specifications for all designs

  • dustproof and product sealed
  • gas and water tight
  • pressure surge protected
  • robust design
  • design in accordance with Atex (dust explosion classes)
  • low space requirement
  • low maintenance requirement
  • low-noise operation
  • flange bearing or pedestal bearing with gland sealing
  • optional conveying screws up to 12 m length without centre bearing
  • shaft-mounted gearbox directly above hollow shaft or spur gear system with coupling
  • special designs

Examples of centre bearings

Standard design with red brass bush
Centre bearing with “Cooper” bearing
Heavy design with red brass bush
Centre bearing for twin-screw

Product brochure

Download Product brochure
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