METHOD OF MAKING ROLL-FORMED DIFFERENT-FLANGE CHANNELS Russian patent published in 1997 - IPC

FIELD: plastic metal working, namely, production of roll-formed different-flange channels in ferrous metallurgy, transport, tractor and agricultural machine engineering and ship building. SUBSTANCE: object of the invention is accomplished by placing shape web at rough technological transitions in shaping plane; bending flanges of shape by total angles inversely proportional to their width values until finally shaping smaller flange and adjacent to it bending zone at last rough technological shaping transition. Cross compression effort and cross motion of shape are realized at last and previous to it technological shaping transitions. At previous to last transition the above mentioned operations are performed at side of convex edge of initial blank towards side of its concave edge until position in which projections of flanges with adjacent to them bending zones are determined by given expressions; at last rough technological shaping transition - at side of concave edge of initial towards side of its convex edge until position in which projections of flanges with adjacent to them bending zones are determined by other expressions. When smaller flange and adjacent to bending zones are finally shaped, wed of channel with shaped flange and adjacent to it bending zone are rotated in direction of bending up smaller flange until achieving (at final technological shaping transition) final rotation angle of web whose value is calculated according to given formula. EFFECT: enhanced quality of roll-formed different-flange channels due to lowered helical torque and reduced width difference of flanges. 5 dwg, 3 tbl