Tube-bending appts. with additional internal heating coil - uses latter to cause softening of tube material in region of outer inductor surrounding transition to curved section

摘要

The outer inductor comprises two rings (1, 2) independently movable in axial and radial directions (4, 3). The tube is driven (5) through both rings (1, 2) while being heated by the internal helical inductor (10) on the end of an axially movable former (11). The region of deformation (6) by the pivotable bending arm (7) is sprayed with cooling water from a perforated collar (16). The region between the rings (1, 2) of the outer inductor is surrounded by a cooling jacket (13) whose axial dimension increases continuously towards the outside of the bend.