Screw Conveyor

Overview

A screw conveyor moves bulk material along a trough by turning a helical screw, the same principle as Archimedes' water screw, applied to powders, granules, and pellets. As the flight rotates, each turn pushes the material trapped against the trough wall forward by one pitch, so the product creeps steadily from inlet to discharge. It is the cheapest, most compact way to move material a short distance horizontally or up a modest incline, and it doubles as a metering device because output is proportional to speed.

The conveyed material rides in the Trough & Cover, closed by a cover, and is pushed by the Screw Assembly turned by the Drive Unit. Product enters and leaves through the Inlet & Discharge spouts, the shaft penetrations are closed by End Seals, an MCU Control Panel supervises the run, and the trough rests on the Supports.

How it works

The working part is the Screw Assembly. A Screw Flight, a continuous helical blade, is welded to the Central Pipe, and as the pipe turns, material held against the Trough Body is unable to rotate with the flight and is forced to advance one pitch per revolution. On longer conveyors the pipe is made in sections joined by coupling shafts, and a Hanger Bearing supports each joint from above so the screw does not sag into the trough.

Rotation comes from the Drive Unit: the Drive Motor feeds a shaft-mount reducer, and a coupling turns the screw at the speed set for the required throughput. Where the screw shaft passes through the trough ends, the End Seals use gland packing and o-rings to keep product in and dust out.

Material is loaded through the Inlet Spout and drops out at the Discharge Spout, with slide gates in the Inlet & Discharge group opening and closing each opening. The Control Panel panel starts the drive, watches for plugging through relays, and interlocks the conveyor with the upstream and downstream equipment so material flow stays coordinated.