| 摘要 |
PROBLEM TO BE SOLVED: To produce a high quality steel shape without biting-in defect, falling down and biting out of a flange part, etc., of a material to be worked by arranging two horizontal rolling mills at a proximate position and at least a pair of calibers different in a web height or a flange width to rolls and continuously rolling a material to be worked. SOLUTION: A beam blank 6 of a material to be worked is subjected to three pass reciprocation rolling with a caliber 31 of a roll 30 and, at a third pass rolling, continuous rolling with a caliber 31 as well as a caliber 41 of a roll 40 to increase a web height. At this time, a material to be worked is firstly rolled with the caliber 31 when biting in a caliber 41 of the roll 40, push-in rolling is made possible by a horizontal rolling mill having the roll 30 so as to completely eliminate slip. Further, for example, a large rough shape steel slab having a web height higher by 50 mm is finished by one pass rolling with continuous rolling of a caliber 42 and a caliber 32, a large rough shape steel slab having a web height higher by 100 mm with a caliber 33, further a large rough shape steel slab having a web height higher by 150 mm is finished by one pass continuous rolling with a caliber 33 and a caliber 43. |
