HOLLOW ARTICLES STAMPING METHOD WITH EXTERNAL FLANGE Russian patent published in 2020 - IPC B21K21/08 B21K23/04 B21J13/02 

FIELD: metal forming.

SUBSTANCE: invention relates to metal forming, particularly, to production of hollow articles with outer flange. Die is used, which contains a punch, a detachable matrix consisting of upper and lower parts having a cavity, and a sliding matrix with a cavity and a counter punch. Two cylindrical workpieces, the diameter of which is less than the diameter of the hollow article, are installed one on the other in cavities of the lower detachable and retractable matrices. Simultaneous action on workpieces involves distribution and closed piercing of one workpiece by way of its extrusion into cavities of lower and upper parts of split matrix and production of second semi-finished product with cross-section expanding towards punch. Then the finished hollow item is removed, and under the semi-finished product a new cylindrical workpiece is installed in the sliding matrix to contact with the counter punch and the semi-finished product and cylindrical workpiece are formed.

EFFECT: as a result, expansion of technological capabilities, reduced metal waste and reduced labor intensity of articles manufacture.

1 cl, 5 dwg, 1 ex