EXTRUDER WITH DUAL FLIGHTED EXTRUSION SCREW

摘要

An extruder has a single screw with two separate inlet hoppers feeding two separate screw flights to deliver two separate materials to a multiple channel shaping die. The screw has separate flights providing separate channels for the separate materials. At the end opposite the hoppers one of the channels opens into a centrally located bore of the screw to receive on of the separate materials and that material flows to the shaping die. The other material flows in the other channel and is discharged to the exterior of the die. In this way a multi-layer product may be effectively extruded.