When an extruder feed system combines pellets with powders and/or regrind flake, the powder and flake are usually the minor ingredients in the mix. But an unusual custom-designed system from CRG Logics Inc., Green Bay, Wis., uses continuous gravimetric blenders to feed very large amounts of mineral fillers, regrind, and powdered rubber from recycled tires together with minute amounts of pelletized concentrates. Regrind is fed at 4000 lb/hr. Calcium carbonate, clay, and powdered rubber together make up roughly another 4000 lb/hr. Meanwhile, specially controlled vibratory feeders add as little as 0.25 lb/hr up to 100 lb/hr of pelletized materials. Such a formulation would typically pass through a twin-screw mixer or extruder and a pelletizer before it could be extruded into sheet. But CRG's customer skips the compounding step and directly extrudes monolayer polyolefin sheet.
CRG Logics, Inc.
610 Baeten Rd. Green Bay, WI 54304
Phone (920) 884-7400 Fax (920) 884-7404