METHOD FOR HOT FORMING OF HOLLOW PRODUCTS Russian patent published in 2002 - IPC

FIELD: metal forming. SUBSTANCE: method involves forming hollow product by single pass of punch; forming outer side surface of product in collapsible bushing located in press container; forming product by redistribution of metal flow and simultaneously extruding metal into main cavity and process projection (radial and axial); removing bottom; selecting sizes of process projections with deformation conditions and working tool strength being taken into account. Method allows hollow products with side surface having periodical section to be manufactured. EFFECT: reduced thermal loading of product and working tool, improved quality of surfaces and geometrical size stability, increased yield, reduced power consumption and labour intensity. 5 cl, 3 dwg