TUBE DRAWING TOOL Russian patent published in 2001 - IPC

FIELD: plastic working and manufacture of straight-seamed tubes. SUBSTANCE: tube drawing tool has draw plate with two conical parts, which are joined with their smaller ends to its cylindrical part, and mandrel fixed on retained rod and provided with conical and cylindrical parts arranged in succession. Mandrel adjoins to rod with smaller end of its conical part. Generatrices of conical parts of draw plate have inclination angles of different value, with entrance angle being greater than exit angle. Mandrel is positioned in draw plate cavity on conical part with smaller angle of taper, with inclination angle of mandrel conical part generatrix exceeding inclination angle of draw plate conical part generatrix, and angle of taper of mandrel and of draw plate being oriented in the same direction. Gap between draw plate and mandrel in mandrel conical and cylindrical parts junction plane corresponds to final thickness of tube wall. Tube drawing tool of such construction provides optimum conditions for deformation of seamed tubes with internal flash and allows cold-deformed tubes with faultless surfaces, including surfaces adjoining seam zone, to be manufactured by means of existing equipment in tube drawing shops. EFFECT: increased efficiency, simplified construction and improved quality of tube surface. 1 dwg