Improved submerged nozzle for steel continuous casting

摘要

A submerged nozzle (1) feeding by gravity with a molten metal or alloy (2) from a container (3) a slab (4) that is under formation in a mould (5) with cooling walls, comprises a form of a vertical tube (6) connected to the overhanging container (3) and terminates at the bottom with a flat diffuser (8) having two outlet ports (9,9') having rectangular cross-section and with an ogivally shaped central divider baffle (14) having a symmetrical contour without corners and adapted to define two passage channels (16,16') for the stream which correspond to said two outlet holes (9,9'). The cross-section (10) for the passage of the fluid at the highest point of the diffuser is narrower than the passage section (11) of the tube (6) according to a ratio 0,6-0,8. In addition the inner side walls (12,12') of the diffuser which are directed towards the narrow sides of the thin mould diverge symmetrically downwards from the median vertical axis (13). Further geometric and functional parameters to be fulfilled by the nozzle are mentioned.