METHOD FOR MAKING EDGE OF COMPLEX GEOMETRY OPENING OF PART Russian patent published in 1997 - IPC

FIELD: plastic working of metal, in particular, sheet stamping. SUBSTANCE: method involves cutting and crimping opening. At the first stage during crimping, local depressions are drawn in zones subjected to maximum loading by deformation. At the second stage, openings are punched so that they make edge on drawn depression bottoms and crimped to obtain required shape. At the stages of drawing local depressions, cutting and crimping of cuttings, the extent of deformation is E(1) = 0.26, E(2) = -0.093, plasticity factor is substantial since extreme deformation values during drawing process are E(1) = 0.405, E(2) = -0.093. Thus, when mechanical characteristics deviate to the worse, pressing characteristics are covered by plasticity factor. EFFECT: improved quality of parts and reduced production cost of thin-sheet rolled products by eliminating breaks in parts. 2 dwg