A tundish nozzle for use in the continuous casting of steel which has a castellated opening to prevent swirling of molten steel when poured therethrough.

The commercial use of processes for the continous casting of steel seems 
destined to take an increasingly important position in contemporary 
steelmaking. Its many advantages in terms of cost, labor and simplicity of 
practice make it very attractive to a highly automated industry. 
Continuous casting is generally defined as the making of a casting many 
times the length of the mold in which it is produced. Molten steel is 
poured into an open bottom mold of the desired product shape. The steel is 
cooled in the mold just enough to harden the exterior surface of the 
casting which forms a shell or container to hold the balance of the liquid 
metal. The partially solidified casting is then continuously withdrawn 
from the bottom of the mold where it is further cooled by water sprays 
until all the metal is solidified. 
Preparing liquid metal for pouring and handling hot bars presents serious 
problems. The secret of success and wherein the problems arise is in 
handling the metal from the time it is poured from the ladle until it 
leaves the mold. 
The tundish plays an important role in this process. The purpose of the 
tundish ladle is to maintain a uniform ferrostatic head. The nozzle opens 
from a lower portion of the tundish. This nozzle, which is so critical and 
important to controlling flow rate and stream cross section to the cooling 
stage mold. It must be characterized by resistance to skulling. "Skulling" 
can be defined as localized build-up of solidified metal and slag on 
interior surfaces of the nozzle and about its exit orifice. 
The bath motion inside the ladle disturbes the pouring flow. This flow is 
also disturbed during pouring because the stream of molten steel swirls. 
Accordingly, it is among the objects of the present invention to prevent 
the molten steel nozzle stream from swirling.

Briefly, in accordance with the present invention, there is provided a 
castellated nozzle, suitable for use in tundish ladles. The nozzle is in 
the form of a cylindrical shell of refractory material defining a nozzle 
opening. The shell contains an upper and a lower end. The nozzle opening 
contains a plurality of vertical grooves extending from the upper end to a 
distance short of the lower end. 
Referring to the drawings, a ladle of steel is placed above a tundish in 
such a position to continuously discharge a stream of molten metal to the 
tundish and at such a rate as to maintain a substantially even bath depth 
in the tundish. A nozzle 2 according to this invention, opens from the 
bottom of the tundish and is so positioned that its bottom orifice 
discharges a stream of substantially constant volume and cross sectional 
dimension into the mold cavity wherein a shaping and skin formation is 
caused to form the steel strip. 
The nozzle 2 consists of a cylindrical shell 8 of refractory material. The 
shell has an upper end 4 and a lower end 6. 
The nozzle contains an opening 10 having a generally circular cross 
section. The nozzle opening tapers outwardly upwardly from a distance 
approximately two-thirds of the dimension between the upper end 4 and the 
lower end 6 to the upper end of the nozzle. 
The nozzle opening 12 below the tapered opening is substantially uniform in 
cross section. The nozzle contains four grooves 14 spaced approximately 
90.degree. apart. The depth of the grooves decreases from the upper end to 
the nozzle opening portion 12. In FIG. 2, it is shown that the grooves may 
also extend horizontally across the upper surface as indicated at 16. 
Accordingly, a castellated tundish nozzle is provided having grooves inside 
the nozzle opening but tapering to the required smooth opening for smooth 
stream exit from the nozzle. 
The dimensions for the tundish and nozzle vary, depending upon the 
installation in which they are used. The shape of the nozzle is also 
variable depending upon the desire of the user. It can be generally 
inverted bell shaped with an orifice opening through the small end of the 
bell. It can be a truncated cone shape with the exit orifice formed 
through the smaller end of the cone. 
It is intended that the foregoing description and drawings be construed as 
illustrative and not in limitation of the invention.