FIELD: plastic metal working, in particular, methods and devices for drawing of thick-walled tubes with intricate internal profile. SUBSTANCE: method includes feed of tube billet together with stepped die insert to conical die and deformation of billet on die insert with fixing of die insert rear end. Use is made of billet with taper angle of entering part smaller than tie taper angle by 1-10 deg to ensure continuous increase of deformation degree of reduction, backing up of billet rear end, and stepped die insert with thread on the step of small diameter for formation of thread on billet internal surface whose runout provides for rotation and self-centering. In this case, at the end of formation of thread on tube internal surface, die is moved relative to die insert through a preset value. The device for embodiment of the offered method has drive of limited motion of die and piston mechanism for moving of die insert installed spring-loaded in rod with its shank placed on bearings and with limiter of axial motion. Located between line of feed of mechanism for provision of pulling force and line of feed of mechanism of backing up of billet from rear end is converter. EFFECT: increased degree of reduction, extended process potentialities, improved process stability and higher quality of articles. 2 cl, 1 dwg
Authors
Dates
1998-06-20—Published
1996-08-26—Filed