COLLECTOR NOZZLE IN A DEVICE FOR CONTROLLING THE OUTFLOW OF CAST STEEL FROM A LADLE OR FROM A TUNDISH

摘要

A collector nozzle (2) in a device for controlling outflow of cast steel from a ladle or from a tundish, which nozzle incorporates at least one main duct (7) placed ringwise round the outlet passage of the nozzle, a first plurality of secondary ducts (12) connecting each of the above main ducts (17) with a portion of said outlet passage and a second plurality of secondary ducts (13) connecting each of said main ducts (17) with the environment outside the nozzle, at the latter's lower end. The main ducts being filled with a current of inert gas under pressure so that the inert gas reaches the area of said passage where otherwise aluminium oxides would become deposited and immediately outside said nozzle to create overpressure of inert gas, thus preventing air from penetrating through the fissures between the nozzle and the tube protecting the flow of cast steel.