SHAFTING
The heavy stub of mirror-smooth, heat-treated shafting is fitted into a stainless steel spacing sleeve. Shaft and sleeve are driven through a heavy duty rubber gasket that fits snugly between the connecting disc and tub. A specially designed slinger fits perpendicular to the shaft between the roller bearing and sleeve and turns with the shaft, adding further protection to the outside mounted bearing from the seal leakage which may follow extensive use.

SHAFT AND FLIGHTS
The spiral-type, half pitch steel flights are welded to a heavy tubular steel shaft. Each spiral screw flight is formed by a special machine to ensure a uniform spiral. The shaft flanges are precision ground after they have been welded onto the heavy tubular steel shaft.

ADJUSTABLE SCREW SHAFT
The adjustable screw shaft makes a unique design. This will allow you to control the clearance between the belly pan and screw flights.

STANDARD NI-HARD ADJUSTABLE WEAR SHOES
Ni-Hard Wear Shoes are standard on GreyStone Coarse Material Washers.

ADJUSTABLE PADDLE
GreyStone paddles are made of heavy duty Ni-Hard. Paddle mounting bases are constructed to give years of trouble-free service life. Water is induced into the tub through the perforated belly pan. Sufficient water should be used to wash out and carry extraneous material out over the overflow flume at the lower tub end. Soluble clay and dust from gravel or crushed stone are eliminated from the material by this abrading washing action. For tougher washing requirements, more paddles can be added to the screw shaft to replace the flights. In this application, the material which is fed into the washer will be retained longer in the scrubbing area for more thorough cleaning. With the addition of more paddles on the screw shaft, your capacity will be reduced and horsepower requirements will be increased. GreyStone Coarse Material Washers are standard 1/2 pitch screw flights. The 2nd and 3rd screw flights are replaced with paddles. If additional paddles are needed to meet your job requirements, the 5th and 6th screw flights can be replaced with our optional paddle arrangement. For specific or severe washing problems that cannot be accomplished with a coarse material washer, please refer to the complete GreyStone line of Log Washers.

EXTERNAL BEARING
GreyStone Coarse Material Washers have externally mounted pillow block bearings that are standard, off-the-shelf components for easy replacement.

LARGE HEAVY DUTY TUB
Strong and rigidly constructed screw washers are designed to provide years of maintenance-free service. GreyStone tubs are all welded construction and are made of heavy steel plate with angle iron skid frame. GreyStone machines have a heavy belly pan which is curved to fit tightly to the screw shaft. During operation, this feature keeps sand from slipping back and increases your production. This feature allows you to make a field adjustment of the clearance between the spiral flight and the belly pan for closer tolerances.

RISING CURRENT BELLY PAN
The rising current water enters the pool from the bottom and filters up, separating fines, dirt and other extraneous matter, which is carried to the top and forced out with the overflow.

HEAVY DUTY SKID FRAME
GreyStone washers are equipped with a heavy duty skid frame. Pull a GreyStone to where it's needed without using a crane…an Exclusive GreyStone Feature.

SEND US A SAMPLE
Send us a sample of your pit run material for a free examination and recommendation for the best equipment selection to meet your requirements.

Coarse Material Washer Specifications SINGLE SCREWS Size Screw Diameter Tub Length Tons/hr RPM hp Max Mat'l Size Water Req. G.P.M. Empty Est. Weight 24" x 18' 24" 18' 60-75 40 15 2" 300-400 7,500 30" x 18' 30" 18' 100-125 35 20 2" 300-500 8,600 30" x 24' 30" 24' 100-125 35 25 2" 250-500 10,550 36" x 18' 36" 18' 150-175 30 25 2" 400-600 10,880 36" x 28' 36" 28' 150-175 30 30 2" 400-600 13,830 44" x 20' 44" 20' 200-250 26 30 2" 500-750 14,200 44" x 32' 44" 32' 200-250 26 50 2" 500-750 18,300 TWIN SCREWS Size Screw Diameter Tub Length Tons/hr RPM hp Max Mat'l Size Water Req. G.P.M. Empty Est. Weight 30" x 18' 30" 18' 200-250 35 2-20 2" 500-700 13,080 30" x 24' 30" 24' 200-250 35 2-25 2" 600-1000 18,900 36" x 18' 36" 18' 250-300 30 2-25 2" 700-1200 16,000 36" x 28' 36" 28' 250-300 30 2-30 2" 700-1200 21,900 44" x 20' 44" 20' 450-500 26 2-30 2" 1000-1500 27,000 44" x 32' 44" 32' 450-500 26 2-50 2" 1000-1500 35,000 These specifications are based on electric motors and on processing gravel. Ample horsepower is provided to handle the material set forth in these specifications. Installation of additional paddles in place of screw flight will reduce your capacity. A high percentage of the maximum sized material of crushed stone will also reduce the plant capacity and require the use of Ni-Hard wear shoes. Throughput capacities are theoretical and approximate and will vary depending on the type of material, moisture content, amount of fines in feed, and operator's ability to feed plant efficiently and maintain equipment. GreyStone does not guarantee plant capacity projections, due to variables itemized above.