FIELD: process engineering.
SUBSTANCE: invention relates to machine building, particularly to metal forming, and can be used for making decorative articles, say, volutes and monograms for arches, etc, from shaped tubes. Prior to bending, the workpiece cross-section is changed to make stiffness ribs by rolling tube wall part inwards at tube sides. Note here that rolling tube wall part rib height and width are selected subject to wall depth. Both ends of the billet are deformed at unrolled sides and cut to required length. Note here that in cutting area said billet is de formed so that stiffness ribs to make straight or practically straight sections with zones of transition from said section to parent material. Straight section length is defined with due allowance for the length before and after cutting and cutting width while transition section length is defined with allowance for pipe profile.
EFFECT: expanded performances, preset pipe profile.
5 cl, 5 dwg
