Dual roll casting machine and method of operating the casting machine

A twin roll casting machine comprising:

• a pair of chilled rolls;
• a pair of pinch rolls for pinching a strip continuously cast by said chilled rolls and feeding the same to a succeeding process;
• an enclosure with lateral side walls confronting widthwise edges of the strip and enclosing the strip in a range from the chilled rolls to the pinch rolls;
• chilled-roll sealing members between the enclosure and outer peripheries of said paired chilled rolls;
• pinch-roll sealing members between the enclosure and outer peripheries of said paired pinch rolls;
• a first swing wall arranged in the enclosure adjacent to a downstream side of the chilled rolls and movable toward and away from a surface of the strip;
• a first sealing roll rotatably supported by a tip end of said first swing wall in parallel with the chilled rolls;
• a second swing wall arranged in the enclosure adjacent to a downstream side of the chilled rolls and movable toward and away from the other surface of the strip;
• a second sealing roll rotatably supported by a tip end of said second swing wall in parallel with the chilled rolls;
• swing-wall sealing members sealingly arranged between a wall of the enclosure and peripheral edges of the first and second swing walls;
• and
• gas supply means for supplying inert gas into the enclosure.