Derrick Corporation

Dry Screening Products

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 filely 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 nearsize 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.

Flo-Divider(TM)

An installation of multiple screening machines or a single screening machine with multiple feed points, such as a Derrick Stack Sizer(TM), requires a well-designed flow distribution system. Custom engineered for each application, Derrick Flo-Dividers are designed to representatively split slurry flows into any number of equivalent streams. Representative flow distribution means that all discharge points receive identical material in terms of mass flow, volume flow, slurry density, and particle size distribution. Derrick design engineers carefully consider the overall process and layout requirements to ensure that the flow distribution system will perform as required over the total range of anticipated flow conditions.

Patented Urethane Screen Surfaces

The development of fine mesh, high open area, urethane screen surfaces is perhaps one of Derrick’s most notable contributions to the science of fine particle separations. While all urethane screen panels are well known for their abrasion resistance, only Derrick’s patented urethane screens combine long life with high open area, capacity, and performance rivaling that of conventional woven wire screens. Moreover, its anti-blinding properties now make it feasible to screen materials previously considered difficult or even impossible to screen.

Processing plants throughout the world have demonstrated significant cost savings through the use of Derrick urethane screens. It’s not uncommon for Derrick urethane screens to last 10 to 15 times longer than conventional woven wire panels. They are also lightweight and easy to install.

With openings as fine as 200 mesh (0.075 mm, 75 microns) and open areas ranging from 35 to 45 percent, Derrick urethane screen surfaces are suited to a wide variety of wet and dry applications.

Not available from any other manufacturer, Derrick has developed this proprietary technology totally in-house. From the design and development of intricate molds, to the unique production equipment needed to manufacture panels on an economic scale, Derrick has again proven itself as the world’s leader in fine screening technology.

A broad range of panel openings are currently available to fit screening machines manufactured by Derrick. Yet, the design and manufacture of custom molds, and even urethane formulations, is an ongoing process. Where a specific opening or preferred panel design is not available, one can be developed. In all cases, a Derrick engineer will work closely with each application to determine the appropriate panel and to address issues such as chemical compatibility or temperature.

Screen Surfaces

High quality screen surfaces are vital to the performance of Derrick high speed screening machines. Derrick fabricates compatible screen panels for use on all models in its equipment line. A number of Derrick screen tensioning assemblies are also available. These greatly enhance the performance of our fine mesh and urethane screens.

Wet Sizing/Dewatering Products

Derrick announces new advances in wet, fine screening technology with the introduction of the patented Stack Sizer. The Derrick Stack Sizer offers industrial mineral producers both high tonnage capacity and high separation efficiency, up to 95%, on an extremely small footprint. This technology offering is most suitable for separations ranging from 6.3mm down to 38 micron.

The Stack Sizer consists of up to five individual screen decks placed one above the other, all operating in parallel. The straight-line linear motion developed by dual Derrick Super G(TM) vibrating motors, together with an angle of inclination of 15 to 25 degrees, produces excellent screening efficiency with high oversize capacity and conveyance. For added efficiency, spray water manifolds with or without repulping troughs are also an option.