| 摘要 |
PURPOSE:To improve rolling performance and the strength of caliber rolls and to permit the use of continuously cast ingots for blank materials by molding the blank materials for rolling of the specific shapes differing entirely from the shapes of products to the shapes resembling the U shape suitable for shape rolling stages in a roughing state. CONSTITUTION:In a roughing stage, a plate-like slab 10 is passed through the 1st caliber 16 to form hollow grooves 26 along the edge parts on both sides of slab 10 and a flat plate-like ingot 30 formed with parts 28 corresponding to joints is rolled. If necessary, the ingot is rotated 90 deg. and is subjected to edging in the flat bottom of the caliber 16. The thickness of the slab 10 is reduced by repetition of such rollings and at the same time the corresponding parts 28 are formed. The ingot 30 is supplied to the 2nd caliber 32, by which the ingot is molded to a roughly shaped ingot 50 of a flat U shape wherein the angle alpha of intersection of the part 34 corresponding to a web and the parts 36 corresponding to flanges is smaller than the angle theta of intersection of a product steel sheet pile 12. If necessary, the ingot is subjected to the edging similar to that mentioned above and the ingot 50 is then supplied to shape rolling and finishing stages. |
