9th ECCC European Continuous Casting Conference – ECCC 2017

Cooling Zones at casting machines are typically equipped with air-mist nozzles to guarantee a wide turn down ratio (typically 1:9) from highest to lowest water flow at a constant spray pattern. To prevent corner cracks the Zones are additionally split into center and margin strips across the casting width. Primetals Technologies DynaJet Flex is the new cooling system to bring the discretization of cooling zones at casting machines to the next level. By using water only nozzles, which are able to be driven with a pulse width modulated signal, it is possible to extend the turn down ratio from 1:9 to 1:15 and higher and save more than 70% of the operational costs by less air consumption compared to conventional air-mist nozzles. The system can be installed and tested on a segment during a planned maintenance cycle. After reinserting the segment into the machine the air for controlling the nozzles is activated. From this time the segment is ready to operate dependent from casting width to guarantee the optimal temperature of slab in and across casting direction. The DynaJet Flex nozzle design has a robust standard flange, where the nozzle is fixed inside the machine. Every available nozzle tip can be mounted on the nozzle head to realize the required spray pattern. This paper shows how a caster is modernized with these nozzles, how the productivity of a caster is increased and how the operations costs are reduced.