COLD ROLL FORMING METHOD FOR LIGHT CHANNEL STEEL WITH LESS DEFORMATION AT CUT END

摘要

PURPOSE:To decrease the deformation at the cut ends of a light channel steel by setting the ratio between the contact projection length between a pressing roll and flange part and flange height at a specific value and exerting the compressing force of a prescribed compression rate toward the corner part from the end edge of the flange. CONSTITUTION:A lower roll 10 and an upper roll group 20 are disposed and the compressing force is exerted to the flange part Kb therebetween. The compression of the flange part Kb s executed near the final stage of cold roll forming. The contact projection height between the pressing roll 21a and the flange part Kb is made >=1/4.5 the flange forming height. The compressing force of which the compression rate is adjusted to a 2.0-4.0% range is further exerted toward the corner part from the end edge of the flange Kb. The residual bending moment and torsional moment remaining in the flange part Kb are thereby made uniform and the light channel steel having the decreased deformation at the cut ends is obtd.