is closed on all sides and which has the casting gap 15 u2032 at the bottom each of the casting rolls 22 24 is supported rotatably at each end on a machine stand 32 and is driven by a motor integrated into the stand according to the invention the casting rolls 22 24 are surrounded by a closable housing 30 which has an opening 30 u2032 in the top for the casting tube 13 which projects into the area between the casting rolls 22 24 and an opening 30 u2033 in the bottom for the emerging metal strip 15 these openings 30 u2032 30 u2033 are sealed and the chamber 33 inside the housing is filled with a shielding gas preferably an inert gas during the casting operation in cases where two or more casting tubes are used it would be possible for several openings 30 u2032 to be provided in the top these openings could be round or slot shaped and there does not necessarily have to be a casting tube in each one it is highly advantageous for this box shaped housing 30 to be a certain distance away from the sides and the top of the casting rolls 22 24 or from the machine stand 32 so that there is no need for the sealing elements required in the case of the casting machine according to the previously cited publication ep a 0 780 177 to seal the metal melt off from the outside in the top this housing 30 is provided with two horizontal doors 35 which are designed so that they can be slid horizontally from the closed position shown in.