| 摘要 |
PURPOSE:To decrease the quantity at which a hot rolling mill trims the transverse end of a product and to improve the yield of the product by forming a channel-shaped recess having a prescribed sectional shape at the center of the side face of the slab. CONSTITUTION:The slab 8 for hot rolling is formed with the channel-shaped recess 10 having an isosceles trapezoidal cross sectional shape at the center of the side face. Said recess is so formed that the two parallel short sides of the isosceles trapezoidal shape are the base. The height (l) of the isosceles trapezoidal shape is made 1.5-9% the thickness of the slab 8 itself. The base angle theta of the isosceles trapezoidal shape is made 5-25 deg. and the long side length of the isosceles trapezoidal shape is made 60-95% the thickness of the slab 8 itself. The above-mentioned slab 8 is cracked T when hot rolled but to the small extent. The quantity of trimming is thus decreased and the yield is improved. |
