APPARATUS FOR CONTINUOUS EXTRUSION OF TUBES Russian patent published in 1997 - IPC

FIELD: plastic metal working, namely tube production. SUBSTANCE: apparatus includes two rolls 1 with passages 2, supporting block 3 and needle holder 4 joined with block 3. Needle 6 is mounted in needle holder 4 by means of hollow bolt 5. Die 7 is arranged in closing unit 8 with extensions 9 closing passages 2 and forming together with rolls 1 and needle holder 4 pressure chamber 10. Plane of extension is inclined by angle $$$ 5 -55 degrees relative to plane passing through rotation centers of rolls; their crossing line coincides with rotation axis of roll corresponding to extension. Die is in the form of driven roll assembly. Buildup telescopic needle has several coaxial members that may be moved one relative to another. EFFECT: enhanced mechanical properties of extruded tubes, enlarged manufacturing possibilities. 3 cl