| 摘要 |
PURPOSE:To hot roll a slab or the like at a uniform width over the entire length by controlling the gap of the 1st vertical rolls in the advancing direction of a material to be rolled and the peripheral speed of the vertical rolls in succession to horizontal rolling mills respectively in the stage of rolling the preceding end part of the said material and in a steady rolling stage. CONSTITUTION:In the stage of broadside rolling of slab 1 with the 1st vertical rolling mill A, the preceding end part of said material is broadside rolled by expanding the gap of vertical rolls 2A, 2A larger than the prescribed gap in a steady rolling stage, thereafter the rolls 2A, 2A are set at the prescribed gap and the material is subjected to rough rolling by steady rolling. In the stage of rolling the preceding end of the roughly rolled material 1' with a horizontal rolling mill B and the 2nd vertical rolling mill C, the peripheral speed of vertical rolls 2B, 2B is set lower than the peripheral speed of horizontal rolls 5, 5, and after the broadside rolling of the preceding end part of the material 1' with the mill B, said part is forced into the mill C. When the preceding end of the material 1' passes through the mill C, the peripheral speed of the rolls 2B, 2B is set at the peripheral speed in the steady rolling stage and the material is rolled by synchronizing the peripheral speeds of the rolls of the mill A, B and C. As a result, the insufficiency in the width in the preceding and succeeding end parts of the roughly rolled material is decreased considerably as shown in the figure. |
