Patent ID: 7323135

Claim:
In a twin roll strip caster which includes a pair of casting rolls equipped with edge dams for forming a molten metal pool, a meniscus shield covering the molten metal pool for blocking contact between the open air and molten metal and brush rolls for brushing the surface of each of the casting rolls, an apparatus for controlling gas layer thickness on the surface of each casting roll comprising: a pair of chambers fixedly mounted on both lateral portions of the meniscus shield in a width direction of a strip; blocking units for blocking introduction of pollutants into the molten metal pool, wherein each of the blocking units includes front and rear barrier members, which are mounted on each of the chambers and in close contact with an outer periphery of each casting roll, and a blower for injecting inert gas toward the outer periphery of each casting roll; operating units for adjusting the thickness and the width of gas layers at both ends of the casting rolls, wherein each of the operating units includes suction lines connected with each chamber to transmit a suction force to ends of each casting roll and a pair of movable plates slidably assembled to both side portions within each chamber for reciprocation by a pair of operating members; and a control unit for controlling the suction force of the suction lines and the movable members by using means for measuring surface conditions and the thickness of the strip.