GB1601165A

GB1601165A - Continuous casting apparatus

Info

Publication number: GB1601165A
Application number: GB8359/78A
Authority: GB
Original assignee: Voestalpine AG
Current assignee: Voestalpine AG
Priority date: 1977-03-18
Filing date: 1978-03-02
Publication date: 1981-10-28
Also published as: BE864824A; FR2383731A1; IT7821164A0; JPS53116226A; SE7801383L; BR7801606A; CA1084666A; DE2811124A1; ES467516A1; IT1093528B

Description

(54) IMPROVEMENTS IN OR RELATING TO CONTINUOUS CASTING APPARATUS (71) We, VOEST-ALPINE AKTIENGESELLSCHAFT, formerly known as VEREINIGTE OSTERREICHISCHE EISEN UND STAHLWERKE-ALPINE MONTAN AKTIENGESELLSCHAFT, a company organised under the laws of Austria, Werk sgelände 4010 Linz, Austria, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a continuous casting apparatus comprising a vertical continuous casting mould and a tundish arranged at a higher level than that of the mould and having an outflow opening which communicates with the mould, via a casting tube which comprises a vertical tube section and which ends below the intended level of molten metal in the mould.

In known apparatus of this kind, the tundish is arranged directly above the mould, the molten metal flowing from the tundish into the mould through a casting tube inserted in the bottom of the tundish and extending vertically all the way from the tundish and into the mould cavity. It is disadvantageous that the tundish covers to a great extent the mould cavity as well as obscuring the bath level therein, as it means that it is difficult to watch and to get to the bath level, particularly in the case of narrow and small casting cross sections. Therefore, watching the bath, getting out slag crusts and removing skulls resulting from an overflow is only very difficult to perform in continous casting apparatus of this known construction.

An object of the present invention is to avoid or minimise these disadvantages by providing a continuous casting apparatus in which the bath level in the mould during casting is accessible without hindrance and can be easily watched, and in which slag crusts and skulls can be removed easily. It is a further object of the invention to provide continuous casting apparatus which minimises the contact between the air and the molten metal being poured from the tundish to the mould, and hence minimises oxidation of the metal being cast. It is a yet further object that the apparatus reduces turbulence of the interface between the molten metal in the mould and the slag or casting powder floating on the metal, as such turbulence leads to higher impurity levels in the cast metal by trapping slag crusts in the metal and by forming non-metallic inclusions.

According to the invention there is provided a continuous casting apparatus comprising a vertical continuous casting mould, a mould cavity in the mould for receiving molten metal therein, a tundish disposed at a level above that of the continuous casting mould but disposed laterally of the mould so as to leave a space vertically above the mould cavity, an outflow opening in the tundish and a casting tube adapted to communicate the outflow opening with the mould cavity, the casting tube comprising a vertically disposed tube section and ending below the intended level of the molten metal in the mould cavity.

In a preferred embodiment, the outflow opening is provided in a side wall of the tundish. As a result, there is good accessibility to the connection between the tundish and casting tube, so that the casting tube can be exchanged more easily and rapidly than hitherto.

Suitably, the outflow opening is closeable with an approximately L-shaped stopper displaceable in a horizontal direction.

The outflow opening advantageously can be closeable with a slider arranged on the outer side of the side wall.

Flow coriditions are favourable, if the casting tube comprises a horizontally extending tube section adajcent the outflow opening, from which horizontal section the vertically disposed tube section extends and projects into the mould cavity.

In order to prevent slag from flowing into the mould, the outflow opening is suitably arranged in a depression in the bottom of the tundish.

Embodiments of the invention will now be described, by way of example only, and with reference to the accompanying draw ing, ,wherein: Figs. 1 and 2 each illustrate one embodi ment, the apparatus being shown only in part and in vertical section.

Referring to the drawings, there is shown a tundish denoted by 1, into which molten steel 2 is poured from a casting ladle not illustrated. At a level lower than the tundish a water cooled continuous casting mould 3 is arranged, the molten steel flowing from an outflow opening 5 of the tundish through a casting tube 6 (Figure 1) or 20 (Figure 2) into the mould cavity 4.

According to the invention the tundish 1 is arranged above, but laterally of the mould 3, so that the space 7 above the mould cavity 4 remains free and the cavity 4 is not covered by the bottom 8 of the tundish.

The outflow opening 5 is provided on the side wall 9 of the tundish, which is the wall nearest to the mould, in the region of a depression 10 of the bottom 8 of the tund ish. Referring now to Figure 1, the casting tube 6 is fastened on the outer side of the side wall 9 by means of a bayonet catch 11.

The casting tube 6 comprises a tube section 12 extending horizontally from the outflow opening 5 to a location approximately verti cally above the middle of the mould, and from the end of this tube section 12 a verti cally extending tube section 13 extends to below the bath level 15 covered with a slag layer 14. That part of the casting tube where the horizontal section turns into the vertical one suitably is reinforced and designed like a tube knee. At the end of the horizontally extending section 12 a connection 16 for introducing flush gas is provided. For lock ing the outflow opening an approximately L-shaped stopper 18 displaceable in hori zontal direction by means of a horizontally arranged connecting rod 17 is provided in the embodiment according to Fig. 1.

According to the embodiment of Fig. 2, the outflow opening 5 is lockable by a staider 19, the casting tube 20 being fastened to the slider. The slider, by being arranged on the side wall of the tundish, is easily accessible and can thus be attended easily.

WHAT WE CLAIM IS: 1. Continuous casting apparatus com prising a vertical continuous casting mould, a mould cavity in the mould for receiving molten metal therein, a tundish disposed at a level above that of the continuous casting mould but disposed laterally of the mould so as to leave a space vertically above the mould cavity, an outflow opening in the tundish and a casting tube adapted.to communicate the outflow opening with the mould cavity, the casting tube comprising a vertically disposed tube section and ending below the intended level of the molten metal in the mould cavity.

2. Continuous casting apparatus as claimed in Claim 1, wherein said tundish is provided with side walls, said outflow opening being provided in one of said side walls.

3. Continuous casting apparatus as claimed in Claim 2, wherein a horizontally displaceable, substantially L-shaped stopper is provided for closing the outflow opening of the tundish.

4. Continuous casting apparatus as claimed in Claim 2, wherein a slider is secured to said one of said side walls at the outside thereof, said outflow opening of said tundish being closeable by said slider.

5. Continuous casting apparatus as claimed in any preceding claim, wherein said casting tube comprises a horizontally disposed tube section adjacent said outflow opening of said tundish, the vertically disposed tube section extending from said horizontally directed tube section into said mould cavity.

6. Continuous casting apparatus as claimed in any preceding claim, wherein said tundish comprises a bottom provided with a depression, said outflow opening being located in said depression.

7. Continuous casting apparatus as claimed in any preceding claim, adapted for continuously casting steel slab.

8. Continuous casting apparatus substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

ing, ,wherein: Figs. 1 and 2 each illustrate one embodi ment, the apparatus being shown only in part and in vertical section.

Referring to the drawings, there is shown a tundish denoted by 1, into which molten steel 2 is poured from a casting ladle not illustrated. At a level lower than the tundish a water cooled continuous casting mould 3 is arranged, the molten steel flowing from an outflow opening 5 of the tundish through a casting tube 6 (Figure 1) or 20 (Figure 2) into the mould cavity 4.

According to the invention the tundish 1 is arranged above, but laterally of the mould 3, so that the space 7 above the mould cavity

4 remains free and the cavity 4 is not covered by the bottom 8 of the tundish.

The outflow opening 5 is provided on the side wall 9 of the tundish, which is the wall nearest to the mould, in the region of a depression 10 of the bottom 8 of the tund ish. Referring now to Figure 1, the casting tube 6 is fastened on the outer side of the side wall 9 by means of a bayonet catch 11.

The casting tube 6 comprises a tube section

12 extending horizontally from the outflow opening 5 to a location approximately verti cally above the middle of the mould, and from the end of this tube section 12 a verti cally extending tube section 13 extends to below the bath level 15 covered with a slag layer 14. That part of the casting tube where the horizontal section turns into the vertical one suitably is reinforced and designed like a tube knee. At the end of the horizontally extending section 12 a connection 16 for introducing flush gas is provided. For lock ing the outflow opening an approximately L-shaped stopper 18 displaceable in hori zontal direction by means of a horizontally arranged connecting rod 17 is provided in the embodiment according to Fig. 1.

According to the embodiment of Fig. 2, the outflow opening 5 is lockable by a staider 19, the casting tube 20 being fastened to the slider. The slider, by being arranged on the side wall of the tundish, is easily accessible and can thus be attended easily.

WHAT WE CLAIM IS: 1. Continuous casting apparatus com prising a vertical continuous casting mould, a mould cavity in the mould for receiving molten metal therein, a tundish disposed at a level above that of the continuous casting mould but disposed laterally of the mould so as to leave a space vertically above the mould cavity, an outflow opening in the tundish and a casting tube adapted.to communicate the outflow opening with the mould cavity, the casting tube comprising a vertically disposed tube section and ending below the intended level of the molten metal in the mould cavity.
2. Continuous casting apparatus as claimed in Claim 1, wherein said tundish is provided with side walls, said outflow opening being provided in one of said side walls.
3. Continuous casting apparatus as claimed in Claim 2, wherein a horizontally displaceable, substantially L-shaped stopper is provided for closing the outflow opening of the tundish.
4. Continuous casting apparatus as claimed in Claim 2, wherein a slider is secured to said one of said side walls at the outside thereof, said outflow opening of said tundish being closeable by said slider.
5. Continuous casting apparatus as claimed in any preceding claim, wherein said casting tube comprises a horizontally disposed tube section adjacent said outflow opening of said tundish, the vertically disposed tube section extending from said horizontally directed tube section into said mould cavity.
6. Continuous casting apparatus as claimed in any preceding claim, wherein said tundish comprises a bottom provided with a depression, said outflow opening being located in said depression.
7. Continuous casting apparatus as claimed in any preceding claim, adapted for continuously casting steel slab.
8. Continuous casting apparatus substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawing.