IMPROVED DESIGN AND PERFORMANCE CHARACTERISTICS OF THE KNEADER RECIPROCATING SINGLE SCREW EXTRUDER

摘要

The new four-flight screw geometry has improved the performance of he reciprocating single screw system. The advantages of the new geometry are especially applicable for products with powder feedstock that are sensitive to temperature and shear effects, such as PVC and powder coatings. Specific improvements are: 1. High conveying stability and linear output with respect to screw speed from the new four-flight screw geometry broaden the process window and permit volumetric scale-up 2. Forced feeding is no longer necessary with the newly designed and improved product inlet. 3. Substantial improvement in output, by a factor of two to three over existing geometry 4. Machine on stream factor is increased by wider operating window for screw configuration, thus potentially increasing on-stream factor. Future development may extend this to calendar film, cable materials and thermoplastics.