Screw extrusion press having barrel temperature control means

A screw extrusion press for processing thermoplastic plastics materials and rubber, comprising:

• (a) a plurality of interconnected and axially aligned barrel portions, each said barrel portion including a solid outer jacket having an inner cylindrical surface and an inner hollow cylinder positioned therewithin, a small gap existing between the outer periphery of said hollow cylinder and the inner cylindrical surface of said jacket so as to permit longitudinal sliding movement of said cylinder relative to said jacket for removing said cylinder, said cylinder having an inner cylindrical surface and being adapted to receive a screw for rotation therein,
• (b) a plurality of circumferentially spaced bores extending longitudinally through said cylinder for receiving a temperature control medium, said spaced bores being arranged in sets, each of which comprise a plurality of adjacent bores,
• (c) intermediate rings positioned between adjacent said barrel portions, said rings having an inner cylindrical surface equal in diameter to the diameter of said inner cylindrical surfaces of adjacent said hollow cylinders so as to form a continuous throughbore for receiving a screw, and means for removably securing adjacent said barrel portions to each other with said intermediate rings positioned and aligned therebetween,
• (d) each said intermediate ring being formed with separate internal annular medium supply and discharge passages through which said temperature control medium passes, and
• (e) guide means associated with said supply and discharge passages, said guide means communicating with said sets of said bores formed in said cylinder and being constructed and arranged so that said temperature control medium delivered to said supply passage is guided into and sequentially through each said bore in each said set in a meandering manner,
• whereby when wear occurs on the inner cylindrical surfaces of said cylinders, the barrel portions and the intermediate rings can be disassembled, the cylinders removed and replacement cylinders installed without requiring replacement of said intermediate rings.