Apparatus for cooling continuous castings

In an apparatus for continuous casting of strands, particularly steel strands, including a mould, mould cooling means, a set of guide rollers arranged to guide the strand coming out of the mould along a desired path, and means for cooling and advancing the strand along its path, an improvement wherein at least in a portion of the zone of solidification of the strand after the mould, the set of guide rollers is arranged in an airtight chamber provided with injection nozzles for cooling liquid, the chamber having opposite ends with a seal at each end and at least one outlet opening equipped with flow control valve means, said guide rollers being arranged to guide the strand coming out of the mould along a first path in which the strand has a vertical component of travel and then along a second substantially horizontal path, said airtight pressurized chamber surrounding the rollers in said first path being divided into compartments separated from one another by horizontal partitions each provided with an opening for the passage of the strand, each compartment being provided on both sides of said path with at least one said injection nozzle for cooling liquid, said compartments being connected to one another through pressure control valve means.