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Chip thickness screening equipment

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Gundlach Multi Roll Crusher

Jeffrey Rader leads the way in total chip preparation with a comprehensive lineup of equipmentfor every stage. From removing gross oversizesto reducing over-thick chips and fines removal,our solutions ensure maximum efficiency and quality. With features like low capital cost, highrecovery rates, and easy maintenance, our equipment is designed for rapid ROI and increased profitability. Discover the superiority of Jeffrey Rader’s systems and equipment for chip preparation.

Jeffrey Rader offers equipment for the four stages of total chip preparation—gross oversizeremoval, over-thick chip removal, size reduction of over-thick chips, and fines removal.Chip thickness screening equipment is used for bark, construction, and demolition waste, refusederived fuel (RDF) and other materials that must be fractioned, separated and cleaned of rocks,metal and sand.Jeffrey Rader screen and processing innovations include scalping screens (RDS), thicknessscreening (Dynagage), fines screens (Rader Wave), chip conditioners (Dynayield) and airdensity separation (ADS) equipment, which assure that delivered chips are the highest quality.Advantages & Benefits:Low capital cost for a rapid ROIHigh recovery rates for increased profitsShips complete with motor, drive assembly, and base for quick installationMetal trap minimizes damage from tramp metalLarge infeed opening ensures that plugging in the Chip-Sizer is eliminatedNo knives to sharpen or damage keeps maintenance costs lowALL BROCHURE TEXT:Systems and equipment designed for total chip preparation.Features/AdvantagesVersatile, Efficient Thickness Screeningfor Pulp ProductionWood costs represent the highest cost component in pulp production and for this reason it isessential to get the highest yield from the wood chips used. And, because the quality of the endproductnever exceeds the quality of the input product, the manner in which wood chips areprepared for pulping is significant.Jeffrey Rader offers equipment for the four stages of total chip preparation—gross oversizeremoval, over-thick chip removal, size reduction of over-thick chips, and fines removal.Gross Oversize RemovalOur Rader Disc Screen (RDS) is a great choice for the removal of grossly oversized woodchips, lily pads, ice lumps, and other foreign objects.These “overs” can be set aside for further processing by rechipping or hogging, after which they can be reintroduced into the incoming chip flow.

The RDS consists of a series of wear-resistant steel discs mounted on heavy-duty shafts, allrotating in the same direction.The size of acceptableparticles passing between the discs is controlled by the interfaceopening between discs and the slot length between shafts. The interface opening (IFO) of theRDS is selected for each application and requirement and can be changed to adapt to changingmaterial characteristics. The infeed to the RDS is also important for maximum efficiency.Over-Thick Chip RemovalOnce the gross overs are removed from the chip flow, the chips can be screened for“thickness.” The normal range for accepted chips for pulpingis 4-8 mm. Chips thicker than 8mm are removed for further processing.Jeffrey Rader offers two types of primary thickness screens—bar type screens and disc typescreens.Our DynaGage™ Bar Screen consists of multiple rigid frame sections containing aseries ofparallel steel bars alternately attached to eccentric shafts.The spaces or slots between the bars are accurately pre-set and locked in place to establish theopen area through which material will pass. When activated, the eccentricity of the shaftscauses the bar to alternately rise and fall in a circular pattern.During the screening process, chips are repeatedly tipped and tumbled by the oscillatingmotion. Chips of acceptable size pass through while over-thick material is retained on the decksand carried over the end.Tramp Metal ProtectionOur Air Density System is then used to remove knots, dense fiber,metal,and rocks from thereject flow prior to the chips going to the over-thick processor.Jeffrey Rader equipment is used in multiple stages of chip thickness screening and chippreparation, from gross scalping screens to fines screens and over-thick processors.Over-Thick Chip Size ReductionOur Chip Conditioner consists of two heavy-duty rolls, with removable, profiled structures, whichrotate towards each other and pull oversize chips between them. The profiled surfaces arealigned so that the pyramid apexes on one roll travel in the valleys of the apexes on theadjacent roll.With normal oversize wood, our Chip Conditioner typicallygenerates less than 1% fines and 2%pins. Chip slicers, by comparison, generate fines up to 8% and pins up to 15%. (Comparison isbased on-3 mm RH fines and-2 mm slot pins.)Due to the reduction in wear parts in contact with material as well as the low-speed action of theconditioning process, thewear-on-wearparts is significantly less than in other forms of oversprocessing.Additionally, our Chip Conditioner offers these maintenance advantages:•All components are simple, off-the-shelf items whichall millwrights understandand are familiar with.•High strengthbolted fasteners make replacing parts quick and easy.•Hardened stainless steel segments are standard.Our Chip-Sizer™ was createdbecause ofindustry concern over the high maintenance cost oftypical rechippers. The Jeffrey Rader Chip-Sizer, the first true no-knife rechipper, operates on a principlelikea wood hog, but with special features which offer a “soft touch” to the chips tominimize the creation of pins and fines. This, along with other patented components, permits itto reduce oversize chips at unheard of efficiencies, plus offer the following advantages:•Low capital cost for a rapid ROI.•High recovery rates for increased profits.•Ships complete with motor, drive assembly, and base for quick installation.•Metal trap minimizes damage from tramp metal.•Large infeed opening ensures that plugging in the Chip-Sizer is eliminated.•No knives to sharpen or damage keeps maintenance costs low.Fines RemovalOur RaderWave™screens provide high-efficiency fines removal with excellent pin chipretention.Andthey are self-cleaning—with no plugging or binding by pins, snow, or ice.Screen decks are easily replaced and there is a wide variety of deck opening sizes andgeometry available. Optional features include adjustable inclination and variable wavefrequency.ChipClassification: Measure, Classify, Control–Unveiling CC4000’s SuperiorityOur CC4000 allows mills to classify chips according to user-defined thickness. Features include:•All controls and functions monitored by a computer compatible with MicrosoftWindows®.•Fully automated chip classification allowing total variability of chip thickness sizeselection.•Superior sample repeatability and accurate chip fraction separation•More accurate processing of larger samples in less time than other classifyingequipment.

TaglineOptions”Jeffrey Rader: Precision in Chip Preparation, Excellence in Screening.””Maximize Yield, Minimize Waste with Jeffrey Rader’s Chip Preparation Solutions.””Efficiency Unleashed: Jeffrey Rader’s Innovations in Chip Processing.””Chip Perfection: From Oversize Removal to Fines Screening, Trust Jeffrey Rader.””Streamlined Chip Preparation, Unmatched Quality: Jeffrey Rader Leads the Way.””Jeffrey Rader: Where Precision Meets Profitability in Chip Processing.””Transforming Chips into Excellence: Jeffrey Rader’s Total Chip Preparation Solutions.””Chip Quality Elevated: Jeffrey Rader’s Comprehensive Screening Solutions.””Empowering Pulp Production: Jeffrey Rader’s Efficient Chip Preparation Equipment.””Innovative Solutions for Chip Processing Challenges: Jeffrey Rader Delivers.”

Gundlach Cage Paktor
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Gundlach Cage Paktor
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Gundlach Cage Paktor
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Air Density Separator

Another Quality Component from the Leader in Chip Processing Technology
Jeffrey Rader pioneered the use of vacuum air systems to remove chip contaminants such as rocks, knots and metal over 40 years ago. Our Air Density Separator’s uniquely-designed control system provides for optimal removal efficiency. The versatility of the ADS provides flexibility in locating chip conditioners and Chip-Sizer™ rechippers, saving costly space and reducing capital investment.
The ADS system’s unique design allows for a curtain of air to be pulled across an adjustable separation chamber. Rocks, knots and unwanted debris drop out of the flow of material at this controlled separation zone while accepts are conveyed to a cyclone.
Aside from protecting downstream equipment, the system’s ability to remove knots and compressed wood greatly improves the pulping process and helps eliminate pulping rejects.
Each ADS system is custom tailored to accommodate your specific process requirement resulting in the elimination of unnecessary energy consumption.


Biofuels & Pellets
equipment for the production of wood chips to liquid biofuel
Biomass Energy
equipment is used in multiple stages of woody biomass processing
Renewable Power
Pulp & Paper
Wood Products / Furniture

Technical Details

  • Technical data available upon request.
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