METHOD OF AND DEVICE FOR CONTINUOUS RING SHAPING OF THERMOPLASTIC SHRINKABLE HOSE ENVELOPES Russian patent published in 2002 - IPC

FIELD: plastics. SUBSTANCE: according to proposed method inner side of spiral shaped hose envelope is thermally treated in inflated state. Prior to fitting into tool, hose envelope is partially filled with compressed gas at minor gauge pressure. Hose envelope is laid over large part of perimeter of spiral, is heated and is set into motion at different velocities on inner and outer side during its movement along spiral. Ring shape is imparted to envelope. Hot air delivered for heating inner side of hose envelope is uniformly distributed over perimeter of hose envelope. Preset temperature is maintained around hose envelope. Invention contains description of device for implementing the method. It provides continuous shaping of hose envelope of any length to ring with at uniform distribution of temperature around hose envelope. Cost of shaping devices is reduced. EFFECT: provision of ring-shaped thermoplastic hose envelopes. 16 cl, 5 dwg