摘要 |
An extruder machine for processing thermoplastic materials such as low density polyethylene, the extruder incorporating a body having a bore therethrough with a rotor or screw journalled therein. The rotor has several successive mixing and pumping sections. The mixing sections on the rotor are multiple flighted defining primary and secondary channels having their discharge and entrances respectively blocked or restricted by annular dam arrangements. The rotor includes a plurality of adjustable dams, arranged across the channels, permitting a variation in the degree of homogenization which may be performed upon the extrudite. The dams may be radially displaceable to vary the distance between the radially outer surface of the dam and the surface of the bore. |