JPS59189047A - Casting mold for continuous casting machine for thin walled billet which permits change in width of billet during casting - Google Patents

Abstract

PURPOSE:To permit easy changing of the width of a thin-walled billet during continuous casting by providing water-cooled metallic blocks for supporting the billet which can be driven independently from short side casting mold blocks which are movable in the long side direction of the casting mold on the lower side of said blocks. CONSTITUTION:Metallic belts 1 constituting the long side of a casting mold are moved by rollers 2 in a direction A. The spacing between the belts is converged and tapered. A cooling fluid is passed between said belts and metallic pads 3 and water-cooled casting mold blocks 4 for the short side are constituted of a tapered part 4a and a fixed width part 4b. Refractories 6 are provided on the inside of said blocks. A molten metal is charged from a nozzle 14 into the mold and a solidified shell 8 on the short side is formed to cast a billet having a width (a). The change of the width to (b) is accomplished by stopping the charging, lowering the molten metal surface down to the end of short side blocks 5, bringing the blocks 4 closer to the width (b) by driving devices 9 and changing the width of the blocks 5 to (b) after passage of the billet having the width (b) through the blocks 5 by drawing of the billet. The width of the thin-walled billet is thus easily changed to about 10-100mm..

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold for a continuous casting machine, and in particular to a mold for a continuous casting machine for thin-walled slabs that can change the width of slabs during casting.

A conventional continuous casting machine mold is constructed by combining a pair of long-side mold blocks that are placed opposite to each other on the long side of the slab and a pair of full-length mold blocks that are placed opposite to each other on the bottom side of the slab. Each mold block has two channels of cooling water inside, and an outer diameter of 1 is used to supply molten metal into the mold.
Since we are using an injection nozzle with a diameter of about 0.00 mm, the distance between the long side mold blocks, and therefore the thickness of the slab, is outside the injection nozzle.

The thickness of the slab that can be produced by such a continuous casting machine is generally 200 to 300 rns due to diameter restrictions.

In the above-mentioned continuous casting machine, as a method of changing the width of the slab during casting, the width of the slab is changed by moving the feeding mold block at an extremely slow speed of about 4 to 10 am per minute. It is also possible to change.

BACKGROUND ART Recently, a belt caster type continuous thin slab casting machine for directly and continuously casting thin slabs for thin steel plates having a thickness of, for example, about 20 to 100 sheets has been developed. However, in such a continuous thin slab casting machine, it is impossible to continuously change the width of the slab by moving the short side mold block at low speed during casting using the conventional method described above. .

The reason for this is that in the conventional continuous casting machine mentioned above, the thickness of the slab is over 200 mm, whereas the metal and solidified shell in the mold are only about 10 to 15 mm thick even at the lower end of the mold. Since the molten metal in the unsolidified part has a large proportion of solidified metal, it can be deformed relatively easily, and the short side mold block can be pushed by the driving force of a cylinder, etc., or the thin solidified metal shell can be pushed out by the pressure of the molten metal. By deforming the width of the slab during casting, it is possible to change the width of the slab by moving the leg mold block at low speed. However, when continuously casting a thin slab with a thickness of about 39 m5, Similarly, the solidified shell thickness is 10~
As a result, the molten metal in the unsolidified portion becomes less than 30%, and the strength of the solidified metal shell is so strong that short-side mold blocks cannot be cast as in the conventional method described above. This is because it is impossible to change the width of the slab by moving it to deform the slab.

The present invention has been made in view of the above-mentioned points, and is provided with a water-cooled metal block for supporting slabs that can be driven independently of the short side mold block, and is provided below the short side mold block that is movable in the long side direction of the mold. The object of the present invention is to provide a continuous casting machine for thin-walled cast slabs, which allows the width of the cast slab to be changed by providing the following.

The invention will now be explained with reference to the drawings.

Fig. 1 diagrammatically shows the upper end mold part of a continuous caster for thin-walled slabs, where l denotes a pair of metal belts arranged oppositely and forming the long side surfaces of the mold or casting space, and are spaced at predetermined intervals. The pair of opposing metal belts 1 are configured to be spaced apart from each other and endlessly circulated in the direction of arrow A by a driving roller 2, and the pair of opposing metal belts 1 are convergently inclined downward from the driving roller 2 to increase the distance between the opposing metal belts. A metal pad 3 is arranged on the back side of each metal bell (1), and the metal pad 3 is arranged on the back side of each metal bell (1), and the metal pad 3 is disposed inside the metal pad 3. A cooling fluid such as high-pressure cooling water is passed between the metal pad and the metal belt through a nozzle hole (not shown) opened on the side of the belt from a cooling fluid path (not shown) formed by a fluid film. The metal belt 1 is compressed to a short side mold block 4 and a short side block 5 which are respectively arranged near the side edges of the metal belt between the metal belts, and the metal belt is cooled.

The short side mold block 4 has a tapered upper part 4a as shown in FIG. 2 and a lower constant width part 4b corresponding to the desired thickness of the thin slab. The inner surface of the mold block 4a is coated with a refractory 6 having low thermal conductivity to delay the formation of a solidified shell on the short side, while the lower constant width portion 4b is a cooling material provided inside the short side mold block 4. It is formed so as to be cooled by the cooling fluid supplied to the fluid passage 7 to form a short side solidified shell 8 (see FIG. 4).

As shown in FIG. 4, the short side mold block 4 has a structure in which it can be moved back and forth along the metal belt 1 in the long side direction of the mold by a driving device 9 such as a cylinder, and thereby the cast slab 1iiiIE change The water-cooled metal short side block 5 for supporting slabs located directly below the short side mold block 4 also has a cooling fluid passageway 0 inside thereof, so as to be able to do so.
A drive device 11 is provided so that the short side block 5 can be moved back and forth along the metal belt 1 in the long side direction of the mold independently of the short side mold block 4.

Next, a method of changing the slab width using the thin-walled slab continuous casting machine configured as described above will be explained.

FIG. 4 shows a case where a slab 12 having a constant width a is being cast, and the molten metal 18 is injected into the mold through the injection nozzle 14. The solidified shell 8 on the pumping side starts growing from the lower end of the refractory 6. After casting the required amount of slabs with slab width a, when changing the slab width to b, pouring is temporarily stopped and the slab 11 is transferred from the short side mold block 4 to the short side of the water-cooled metal for slab support. The block 5 is lowered to the upper end position as shown in FIG.

Next, the Shibe mold blocks 4 are moved forward toward each other, and the interval between the two pressurized mold blocks 4 is changed to the slab width. After that, the injection is restarted to bring the molten metal to the upper surface level C shown in FIG. After pouring is finished, the slab is lowered again, and after passing through the water-cooled metal pressure feeding block 5 for supporting the slab, the short side block 52 is moved to the position where it corresponds to the short side mold block housing. advance each.

The above method is for changing the width of the slab to a narrower width, but when changing the width of the slab to a wider width, the moving order of the short side mold block 4 and the water-cooled metal short side block for supporting the slab 5 is reversed. It can be changed by

According to the present invention, the two water-cooled metal short side blocks for supporting slabs are installed directly below the short side mold block, and the width can be easily changed in a thin slab continuous casting machine by operating both feeding blocks separately. You can get the effect that you can.

[Brief explanation of the drawing]

Fig. 1 is a diagrammatic longitudinal cross-sectional view of the mold part of a continuous thin-walled cast slab casting machine according to the present invention, and Fig. 2 shows a short-side mold block according to the present invention and a water-cooled metal sudden block for supporting the cast slab immediately below it. A perspective view, FIG. 3 is a vertical palindrome showing the actuating devices connected to the T=side blocks shown in FIG. 2, and FIGS. 4 to 6 are route diagrams for explaining the operation when changing slab width. . 1... Metal belt 2... Drive roller 8...
Metal pad 4...Gube mold block 5...
Water-cooled metal short side block for supporting slab 6... Refractory material
9,11... Drive device.

Claims (1)

[Claims] L A pair of metal belts (1) that are moved by a drive roller and are arranged facing each other at a predetermined interval and constitute the long sides of the mold.
and a pair of hedge mold blocks (
4), a water-cooled metal short side block (5) for supporting slabs placed directly below each short side mold block, and moving the short side mold blocks back and forth along the metal belt in the long side direction of the mold. and a device (11) for moving the water-cooled metal short side blocks for supporting slabs back and forth along the metal belt in the long side direction of the mold separately from the movement of the short side mold blocks. The short side mold block (4) has an upper narrowed part (4a) whose width is tapered downward, and a lower constant width part (4b) extending with a constant width at the lower end of this upper narrowed part (4a). and tin
Continuous casting of thin-walled slabs that enables the width of the slab to be changed during casting, characterized in that the inner surface of the bow upper narrowing part (4a) is protected by a refractory (6) with low thermal conductivity. Machine mold.