APPARATUS FOR CONTROLLING SHAPE AND INTERNAL QUALITY OF SLAB IN TWIN ROLL STRIP CASTER

摘要

PURPOSE: An apparatus for controlling shape and internal quality of slab in twin roll strip caster is provided to improve shape quality and actual yield of the slab by preventing hot band or bulging that is solidification delay of the edge part of the slab through adjustment of widthwise cooling power of casting rolls. CONSTITUTION: The apparatus comprises a pair of left and right chambers(30) fixed to front and rear parts of meniscus shield(9) in a width direction of casting slab and formed in such a sectional shape that the outer circumferential surface of casting rolls(1,1a) is oppositely directed to an opened lower end of the chambers; a blocking part comprising front and rear blocking members a lower surface of which is longitudinally closely adhered to the outer circumferential surface of the casting rolls, and which are removably installed on front and rear sides of the chambers, and a blower for injecting an inert gas onto the outer circumferential surface of the casting rolls so that inflow of contaminants into molten steel pool is cut off; an operation part(50) comprising a pair of suction lines(51) communicatingly connected to both sides of an upper surface of the chambers respectively so that the suction lines transmit suction force to both edge parts of the casting rolls, and a pair of operating members(55) for reciprocating a pair of moving plates(52) slidingly assembled into both sides in the chambers to adjust thickness and width of gas film at both edge parts of the casting rolls; a gas supply part(70) one end of which is connected to a gas injection port(30a) formed on the center of an upper surface of the chambers, and which supplies inert gas into the chambers by connecting the other end of nitrogen and argon gas supply lines(71,72) to nitrogen and argon gas tanks(73,74), wherein control valves are formed at the middle part of length of the nitrogen and argon gas supply lines; and a control part(60) for controlling suction force of the suction lines, the operating members and gas supply amount of the nitrogen and argon gas supply lines based on measured values of a measuring means for measuring the surface state and thickness of the casting slab.