| 摘要 |
<p>PURPOSE:To reduce seam flaw and overlap and to improve the yield by equalizing the distance between two contact points on two slopes of a vertical roll and operating the number of passes and the forming torque for forming terminal parts from the rolling conditions of total forming quantity, roll diameters, etc. CONSTITUTION:There is equipped an end part forming machine 3 which has a 1st slope connected through a barrel part 12b and having an inclined angle 30-60 deg. to the horizontal and a 2nd slope connected with this 1st slope and having an inclined angle 10-20 deg. and is provided with a spool type vertical roll 12 having a distance between the 2nd slopes equal to the thickness of a material to be rolled. The formed amount of the end parts of a hot rolling slab 30 is made 10-60mm/pass, more than one pass are rolled and the total formed amount is made 20-80mm. For this purpose, an arithmetic part is equipped to calculate the number of passes to form the end parts and the forming torque from the total formed amount, the roll diameters, the rolling speed, the rolling temperature, the slab size and the amount of carbon. Consequently, the edge parts of the slab are preformed preceding the rough rolling so that rolling flaw are minimized and the seam flaw and overlap can be reduced.</p> |
