Table of Contents
Gold Trommels & Scrubbers are noted for economy and efficient performance in cleaning sand, gravel, crushed stone and various ores. These machines are ruggedly constructed and are designed for excellent results with a minimum of water, power and maintenance. Time and again users report lower cost per ton with Gold Trommels & Scrubbers.
Gold Trommels & Scrubbers will process fine and coarse feed simultaneously or will remove fine materials first through use of a desander. These units successfully handle product sizes up to 8″. The EHD Extra Heavy-Duty Scrub-masters should be used if feed is larger than 8″. With extremely tough clay conditions Log Washers rather than Scrubbers are recommended.
Trommel Construction Details
BASE FRAME is made of heavy-section beams and channels, securely braced and gussetted for maximum rigidity. This insures continual alignment of all bearings, shafts, trunnions, thrust rollers and other components mounted on the frame.
SCRUBBER CYLINDER is constructed of rolled plate sections electrically welded at all seams, forming a circular drum capable of withstanding continual shock loads.
Abrasive-resistant steel liners bolted to the drum are easily replaceable to compensate for normal wear. Lifter shelves, plows and/or angled flights as required for the application are bolted inside the scrubber cylinder.
FEED CHUTE has a flanged opening of generous size to accept materials from conveyors, screens, feeders, crushers or other equipment. The bottom of the feed chute is equipped with easily renewable liners. A standard threaded pipe sleeve is welded to and projects from the feed chute, serving as a means of introducing water at the feed end of the scrubber.
OPTIONAL DESANDER consists of a large circular perforated plate which serves as the feed end of the scrubber. An opening in the center allows entry of materials from the feed chute, and screen cloth of desired size is bolted to the plate. A fabricated steel hood, flanged and split at the center, surrounds the desander at the feed end of the scrubber drum to prevent separation and loss of valuable material. This hood converges at the bottom and is flanged for attachment of a closed flume for transfer of the fine sizes.
DEWATERING SCREEN EXTENSION consists of a circular perforated plate bolted to the discharge end, the plate being covered with renewable screen cloth of desired size for separating fine material from the coarse.
DRIVE AND GEARS. The scrubber is driven from electric, gasoline or other power units through a standard V-belt drive to a grooved, balanced flywheel mounted on the end of the scrubber countershaft. The countershaft is supported in three self-aligning bearings, one at the flywheel hub, the other two on either side of the drive pinion. The cut steel pinion mates with a two-piece, split, cut, semi-steel ring gear bolted securely to a steel gear base ring welded to the scrubber cylinder.
TIRES AND TRUNNION ROLLERS. Locomotive steel tires around the shell mate with generous size trunnion rollers. Trunnion rollers also have renewable tires. Anti-friction roller bearings are mounted inside the trunnion roller hubs, the bearings being secured to stationary trunnion shafts which are supported by the base frame. The trunnion roller shaft support bearings are adjustable to compensate for normal trunnion wear and to assure continued trunnion roller alignment.
Scrubber Operation
Fresh water and material being cleaned are introduced through the feed chute. As the cylinder revolves, the raw feed is retained by centrifugal force on lifting shelves until it nearly reaches the top. Cascading and tumbling of the aggregate upon itself and on the liners breaks down the softer materials and dissolves dirt, loam and other foreign materials into solution. At the discharge end the aggregate passes over a dewatering screen extension. When the optional desander is used, fresh water introduced at the discharge end flows opposite to the direction of aggregate travel, carrying sand through a perforated plate covered with easily-renewable screen cloth at the feed end. Sand also is removed at the dewatering screen extension. Water and sand from this screen extension then is flumed back to join the slurry from the desander. This fine material slurry generally is then passed to a Sand Classifying Tank or Screw Washer for dewatering and further handling.
Perfect Tire Concentricity
A unique assembly technique assures that the locomotive steel tires are in perfect concentricity with the drum—a factor very important to smooth, quiet operation and to minimizing tire and gear wear.
Capacities
In determining capacities more precisely, these and other factors should be considered: type of feed, water volume, tenacity of waste content. The Stone engineering staff gladly will recommend the size scrubber required for any application.
Scrubber or Log Washer
With a broad background of experience in both types of washing equipment, McLanahan and Stone strongly recommends that Log Washers rather than Scrubbers should be used in extremely tough clay conditions. In other cases, McLanahan H-D Scrubbers perform very well on all size feeds up to 8″ (up to 20″ for EHD Scrub- masters).
