New Derrick 8-deck high-capacity SuperStack® screening machine
More effective use of screen area and increased capacity results from the front-to-back screen tensioning system that tensions the panel in the direction of flow rather than side to side. In addition to increasing productivity, the tensioning system reduces screen panel changing time by 80 to 90 % compared to side-to-side tensioning. A full range of Derrick Polyweb® urethane screen panels are available for the SuperStack, from 53 to 1000 µm with slotted openings. An optional repulp spray system introduces free water into replaceable rubber wash troughs to help undersize material pass through screen openings.
Dual oversize launders (one per side) and a single undersize launder eliminate the need for a large hopper, minimizing height requirements. Each feeder has an easily removed front cover to facilitate maintenance and debris removal. Custom designed inlet pipe configurations are available from Derrick if needed to meet equipment layout requirements. The Flo-Divider™, which equalizes flow from the feed source to each deck, is available in a number of discharge outlet configurations from 2-way to 16-way.
Dual vibratory motors are positioned directly over the upper screen frame to deliver linear vibratory motion to all 8 screen decks. The motors have an internal oil lubrication system that eliminates the need for a separate lubrication system, while providing long-term maintenance-free operation and low sound production.
Dan Cook of American Silica describes their experience with the SuperStack: “We’ve seen a vast improvement in quality and efficiency.” Cook is especially pleased with the ease of changing the SuperStack screen panels. Noting the productivity improvement, he comments: “Plant capacity has increased by about 35 %. We’ve gone from 700 tons per shift to 950 tons per shift! And we believe it can handle more than what it’s rated for.”