Dry Screening

A wide assortment of single deck and double deck dry screening machines are available from Derrick. Each machine is custom engineered for the required duty and installation, and comes complete with the appropriate feed box, product collection hoppers, and dust enclosure. The covers and doors on the dust enclosures, together with side openings on the vibrating screen frame, permit easy access for inspection or screen surface replacement. The lower deck screen surfaces on double deck machines can even be replaced without having to remove the upper deck screen surfaces. Compared with other types of vibrating screens, structural requirements are considerably less with Derrick screens since they transmit virtually no dynamic load to the surrounding support structure.

The high frequency, low amplitude motion produced by Derrick's complete line of vibrating motors produce a unique vertical-elliptical movement that quickly conveys oversize particles down the screen. This action produces a thin bed of particles, leading to increased capacity and efficiency. Single or multi-angle screen bed configurations are available, depending upon the separation goals and the amount of oversize and near size particles. If required, multiple cut points are easily obtained with various split hopper arrangements. Keep in mind that for high tonnage separations, it is usually more cost effective to use a combination of single and/or double deck Derrick screens than machines with three or more decks.

Derrick's worldwide dry screening success has also been driven by its continuing development of advanced, non-blinding, screen surface technology. For example, materials with high moisture content that would normally blind other types of equipment are successfully screened using Derrick's unique floating backing wire system.