METHOD FOR MAKING SYMMETRICAL SHAPES Russian patent published in 2004 - IPC

FIELD: plastic metal working, possibly small-batch production of symmetrical wide-flange bent shapes, mainly with coating. SUBSTANCE: method for making symmetrical shapes during successive transitions for bending up members of shape in rolls of shape bending mill comprises steps of additionally bending up flanges in interstand space by 3 - 4 degrees; during first transition in mean portion of bent up flange forming groove (to be straightened) turned outside by its convexity and having constant joining radiuses; during second transition bending up flanges while straightening groove; in interstand zone at least between two successive transitions simultaneously with additionally bending up flange performing cross bending of said flange in such a way that its convexity is turned outside; then straightening flange during next transition in closed roller grooved pass; determining height of straightened groove according to dependence given in description of invention. EFFECT: reduced degree of non-planeness of flanges at integrity of coating, lowered number of transitions, enlarged manufacturing possibilities, lowered production cost. 4 dwg, 1 ex