METHOD FOR DRAWING DIFFERENT-THICKNESS WELDED SHEET BLANK AND DIE SET FOR PERFORMING THE SAME Russian patent published in 2000 - IPC

FIELD: cold sheet forming, possibly making parts of motor vehicle bodies. SUBSTANCE: method comprises steps of loading different-thickness sheet blank having stepped portions on one surface into rigid drawing die set including punch, die with seat for holder and holder. Braking constricting ribs are arranged on seat for holder. On face of holder at side of stepped portions of blank polyurethane gasket is fixed. At acting upon blank by pressure effort from side of holder and braking ribs polyurethane gasket provides formation of stepped holding surface engaging with stepped portions of blank. Gasket has thickness consisting 7-10 thickness values of sheet of welded blank with maximum thickness. EFFECT: possibility of drawing different-thickness blank without ruptures and riffles. 4 cl, 2 dwg