| 摘要 |
PURPOSE:To reduce segregated impurity at center part of a cast slab by grasping flowing force of molten metal at the end stage of solidification from casting condition, finding strain speed at axial part of the cast slab balancing with the flowing force and applying draft force corresponding to this on the cast slab surface. CONSTITUTION:Plural pairs of bending rolls 24 are arranged at vertical drawing part below the mold and also a light draft device, 10 providing many light draft rolls 16 are arranged below these. Each roll 16 is connected with rod 18 of a draft cylinder 19 in each roll chock 17 and the cylinder 19 is connected with each hydraulic control device 42. The flowing force (a) developed in the molten steel 34 by each setting condition for casting inputted through a CPU 40 is arranged by a finite element method and the strain speed of the solidified shell 32 canceling this is found. Next, the draft quantity corresponding to this is calculated, to control the cylinder 19. As the flowing of condensed molten steel at the end stage of the solidification is prevented, the segregation of impurity in the cast slab is reduced. |
