Method of rough rolling rough rolling hole-type and H-shaped steel of H-shaped steel

摘要

PROBLEM TO BE SOLVED: To provide a rough rolling pass for wide flange shape steel and a rough rolling method for wide flange shape steel that can eliminate as much as possible irregularity in shape of a flange portion in a material copper piece and further stabilize shape of a beam blank even when a second splitting rolling pass is continued to an expanding rolling pass to set the rolling pass to a roll body length.;SOLUTION: In a rough rolling pass for wide flange shape steel, one wall surface 12a of a second protruding portion 12 of a second splitting rolling pass k-2 is also used as one lateral wall of an expanding rolling pass k-3. The wall surface 12a and a wall surface 12b of the second protruding portion 12 of the second splitting rolling pass k-2 respectively comprise: first slopes 12a1 and 12b1 where an angle θ21 between a perpendicular L relative to a roll body length direction and the surfaces is the same as an angle θ1 between a lateral wall surface 13d of the expanding rolling pass k-3 and the perpendicular L; and second slopes 12a2 and 12b2, continued to the ends of the second protruding portion 12 of the first slopes 12a1 and 12b1, where an angle θ22 between the perpendicular L and the surfaces is larger than the θ21.;COPYRIGHT: (C)2015,JPO&INPIT