Trough screw Trough Screw Upstream or downstream of the storage, the transport of powders may be provided by an Archimedean screw conveyor. With high experience, ISERCO develops and manufactures the device in direct connection with the storage of bulk. The Archimedean screw allows the transfer of powders or pellets from point A to point B. This transfer can also be vertical with limited inclinations at 45 °. Unlike a tubular screw, the trough screw allows the installation of a cover on top. This provides easy access to the inside of the sheath which simplifies maintenance and cleaning of the screw. Archimedean screws are usually made of stainless steel but can also be made of galvanized steel.