METHOD OF EXTRUDING THIN-WALLED HOLLOW ARTICLES Russian patent published in 2018 - IPC B21K21/04 B21J13/02 

FIELD: technological processes.

SUBSTANCE: invention relates to the treatment of metals by pressure and can be used in the manufacture of thin-walled hollow articles. Workpiece is placed on the end surface of the ejector, which has spiral hollows of depth decreasing toward the center. Outer ends of the branches of the depressions face the edge of the end face of the ejector at points equidistant along the circumference of the said surface. Inner ends of the branches of the depressions emerge on a circle with a diameter equal to 0.2–0.3 of the diameter of the ejector. Transverse profile of the depressions has a coaxial axis of the ejector, a back wall 0.6–0.8 mm high, a bottom surface 2–3 mm wide perpendicular to the axis of the ejector, and a leading edge oblique at an angle of 30–40° to the bottom surface. When the workpiece is deformed, the ejector displaces the second volume of the workpiece metal, equal to the second volume, fed by the punch to the deformation center, into the zone of the product wall forming.

EFFECT: result is reduced unevenness of the deformation and the technological force of extruding thin-walled hollow articles.

1 cl, 4 dwg