The main purpose of nozzles in continuous casting processes is the cooling of the strand surface. This spray water cooling is the only controllable part of the secondary cooling process and is therefore a major factor in determining maximum productivity and optimum quality of continuous casting processes.
In the secondary cooling process the spray nozzle arrangement and process parameters determine the characteristics of spray water cooling. The spray nozzle arrangement defines the area on the strand surface where spray cooling occurs. Process parameters such as operating pressures and flow rates determine the cooling intensity and distribution on the strand surface.
Heat extraction from the strand surface is a result of both, nozzle arrangement and process parameters which therefore define the cooling and solidification process. As a premium nozzle manufacturer Lechler does not only supply prime quality nozzles, systems and accessories; Lechler also provides detailed engineering and measurement knowledge and services in the areas of both nozzle arrangement and process parameter optimization.
The optimization potentials in nozzle arrangement include nozzle alignment, header and segment pipe design and liquid distribution optimization for new and existing systems. For process parameters optimization potentials lie in the choice of the atomization type (air-mist or water only), spray kinetics, spray impact and the correlated cooling efficiency (measured surface heat transfer coefficient).
The requirements on secondary cooling of the casting processes are varying with section size and steel grade. Therefore special nozzle types are available to meet the multiple requirements and provide the optimum cooling solution for each secondary cooling system.
In addition Lechler provides capabilities in continuous casting process simulation which can be utilized for secondary cooling process optimization, e.g. by optimizing the steel grade specific spray plan or predicting the maximum casting speed for an upgraded secondary cooling system.