JPS62183947A - Tundish for continuous casting machine - Google Patents

Abstract

PURPOSE:To prevent entrainment of molten slag into molten steel in a tundish by arranging a refractory brick made tube with cylindrical shape at outside of a long nozzle, at pouring the molten steel into the tundish from a ladle through the long nozzle. CONSTITUTION:One pair of weirs 22 are arranged at inner part of the tundish 16 for continuous casting and separated to slag floating separation zone 24 and molten steel flowing-out zone 26 toward continuous casting molds 12, 14, and flowing-out holes 27 are arranged at lower parts of the weirs 22. The long nozzle 34 from the ladle 30 is inserted into the slag floating separation zone 24 and refractory made cylindrical tube 28 is set at outside of the end part of the long nozzle 34. The molten steel in the ladle 30 is flowed into the refractory made tube 28 in the slag floating separation zone 24 for the tundish 16 through the long nozzle 34, and then flowed in the slag floating separation zone 24 between the tube 28 and the weirs 22 after diving the tube 28 toward underside, while entraining the molten slag on the molten steel surface, to float up and separate only the molten slag. Further, the molten steel is flowed in the molten steel flowing-out zone 26 through the holes 27 in the weirs 22 and the molten steel without mixing of the molten slag is poured into the molds 12, 14 for the continuous casting equipment through the nozzles 18, 20 at the tundish bottom.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a tundish for a continuous Ml-making machine that continuously supplies molten steel supplied from a steel tap to a mold.

[Prior art] A continuous casting machine includes a mold and a supply m of molten steel to be supplied to the mold.
A tanditshu is provided to adjust the temperature. Molten steel is injected into the tundish from a ladle, but in the case of continuous casting, is it poured into the tundish? The next mWA is injected into the steel while leaving the W steel in place.

As shown in FIG. 3, a conventional tundish 1 is provided with a weir 3 to control the flow of molten steel and promote floating separation of slag 2. In this case, Tanditsh 1
The inside is divided into a flotation area 4 where slag is floated and separated, and an outflow area 5 where molten steel continuously flows out into the mold. The bottom of the tundish in the outflow area 5 is provided with a nozzle (not shown) for flowing molten steel into the mold. A hole 6 is formed in the lower part of the weir 3, and the molten steel from which the slag has been floated and separated flows into the outflow area 5 through the hole 6, and the slag floating on the warm blood flows into the outflow area 5. is weir 3
This prevents the outflow from flowing into WAyi5.

On the other hand, when pouring molten steel into the tundish 1 from the tundish 1, the tip of a long nozzle 7 attached to the nozzle of the tundish 1 is injected toward the flotation separation area 4 in the weir 3 of the tundish 1.

[Problems to be Solved by the Invention] However, when pouring molten steel into the tundish, if the clean surface of the molten steel in the tundish is below the long nozzle, the slag on the surface of the molten steel is washed away by the injection flow from the long nozzle. The slag that is pounded in and floating on the surface of the hot water is one meter long.
It gets mixed into.

The slag mixed into the molten steel flows through the holes 6 formed in the weir 3 together with the molten steel. There is a drawback that it flows into 4ilil15. Such hammering of the slab occurs at the initial stage of injecting molten steel, but once the molten steel is supplied and the warm blood rises, the tip of the nozzle is immersed in the molten steel, so the slab is not hammered into the molten steel. Therefore, in order to prevent such slag being driven into the tundish, it is conceivable to form the long nozzle 6 long and to immerse the tip of the long nozzle 6 into the molten steel remaining in the tundish from the beginning.

However, in this case, since air is present in the long nozzle before molten steel is injected into the tundish, it is necessary to form an air escape route at the tip of the long nozzle. When a hole is formed in the long nozzle, the strength of the long nozzle is reduced, and air enters through the hole during injection of molten steel, resulting in a reduction in the sealing performance of the long nozzle.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a tundish for a continuous casting machine that can prevent slag from being entrained.

[Means for Solving the Problems] The tundish of the continuous casting device according to the present invention floats and separates slag in the molten steel in the tundish of the continuous casting device into which molten steel in a ladle is injected through a nozzle. A weir that separates a flotation separation area and an outflow area from which molten steel flows into the mold, and a pipe that is interposed on the molten surface in the flotation separation area and into which a long nozzle is inserted and into which the molten steel is injected. injected through.

[Operation] When molten steel is injected into the tundish through the long nozzle, the slag present in the pipe is knocked in, but is floated and separated by the weir. After that, the slag on the molten W4 surface is prevented from penetrating into the inflow region by the pipe, so that substantially no slab exists on the molten A4 surface in the inflow region. Therefore, the slag is prevented from being hammered into the structure.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2 of the accompanying drawings. Continuous casting tffilO
, the molten steel in the ladle 30 flows into the tundish 16 through the long nozzle 34, and the molten steel in the ladle 30 flows into the tundish 16 through the long nozzle
6 is injected into two molds 12 and 14 in which the flow is divided.

The inflow of the stock 30 is controlled by a sliding nozzle.

Tanditsh 16 has a pair of 1lf approximately in the center.
22 are provided, and in this order, a flotation separation area 1ii124 controls the flow of molten steel in the tundish 16 and floats and separates slag, and an outflow area 26 where molten steel flows out from the nozzle and is injected into the mold. It is divided into This weir 2
2 has a hole 27 formed below it that communicates the floating fraction Ill region 24 and the outflow region 26. A cylindrical refractory brick pipe 28 is disposed inside the slag flotation separation region 24 where the flow of molten w4 is regulated by the weir 22.

This pipe 28 interposes the molten steel in the slag flotation separation region 24 on the molten metal surface and defines an inflow region 29 into which the molten steel flows. In this case, the tube 28 is simply suspended in the molten steel, and about half of it is immersed in the molten steel due to the balance of specific gravity. Part of it is immersed in the molten steel surface, and the other part protrudes from the wet surface. The tube 28 is formed into a cylindrical shape, and has a radius that is 20 to 30 m+ larger than the diameter of a long nozzle 34, which will be described later.

On the other hand, a nozzle 32 for pouring out molten steel is formed below the chamber 1130 in which molten steel is stored.
A long nozzle 34 is attached to the.

Next, the operation of this embodiment will be explained. Continuous casting 1
When carrying out so-called continuous casting using the tundish 110, the next molten steel is poured while the molten steel remains in the tundish 16. In this case, the ladle 30 containing molten steel is suspended from a crane, and the ladle 1-1 is attached to the tundish 16 of the continuous casting 1j110, and the long nozzle 34 is attached to the nozzle 32 of the ladle.

Next, the tip of the long nozzle 34 is guided into the pipe 28 and positioned above the slag floating on the surface of the molten steel. Next, although not shown, the plug of the nozzle 32 is removed and the molten steel is injected into the tundish 16 from the tundish 130. In this case, the molten steel flowing out from the tip of the long nozzle 34 is
The molten steel flows under the pipe 28 as shown by arrow A while hitting the slag on the molten metal surface, and stays in the flotation separation area 24.

The slag once rolled up in the molten steel floats between the pipe 28 and the weir 22, so the slag floats Mia2 in the weir 22.
Slag accumulates only on the hot water surface in step 4. The floated slug is prevented by the tube 22 from returning to the injection region 29 again. Therefore, when injecting molten steel, injection fr4 of molten steel
Since slag does not return to the area, there is almost no slag involved when pouring molten steel. Next, the molten steel from which the slag has been removed flows into the region 26 through the hole 27 formed at the bottom of the hole 22. Therefore, according to this embodiment, when pouring molten steel into the tundish 16, it is possible to reliably prevent slag from being involved.

When molten steel is supplied from the long nozzle 34, the level of the molten steel in the tundish 16 gradually rises, and the molten steel is supplied to the long nozzle 3.
The tip of No. 4 is immersed in the molten steel. Therefore, in this case, the molten steel flowing out from the tip of the long nozzle does not involve the slag on the molten metal surface.

On the other hand, the molten steel in the tundish 16 is continuously supplied from the outflow region 26 to the mold 12 or 14 via the long nozzle 18 or 20.

According to this embodiment, the amount of slag entrainment can be reduced to about 1/4 to 1/3 compared to the conventional method.

This invention is not limited to the one embodiment described above, and can be modified in various ways without departing from the gist of the invention.

For example, the pipe 28 for isolating the 1.1ifi slag was suspended in the molten steel and interposed on the molten metal surface, but the pipe 28 is not limited to this, and may be attached to the weir 22 and supported.

Further, the same effect can be obtained by supporting the ladle from the long nozzle via a support member.

Further, in the above embodiment, the tundish with two extending nozzles was used as an example, but the invention is not limited to this. A similar effect can be obtained.

[Effect of the invention] According to this defense, a pipe defining an inflow area into which molten steel flows is provided inside the tundish 11 above the molten metal surface, and this pipe prevents slag from flowing into the inflow area. This prevents slag from getting caught up when pouring molten steel.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view of a tundish according to an embodiment of the present invention, and FIG. 2 is a continuous casting 3 using the tundish shown in FIG. FIG. 3 is a partial cross-sectional view showing a part of a seashore, and FIG. 3 is a cross-sectional view showing a part of a conventional tandish.

Claims (1)

[Claims] In a tundish of a continuous casting machine into which molten steel in a ladle is injected through a nozzle, a weir partitions a flotation separation area where slag in the molten steel is floated and separated and an outflow area where molten steel flows into a mold; 1. A tundish for a continuous casting machine, characterized in that the tundish comprises a pipe interposed above the molten steel surface in a flotation separation region, into which a long nozzle is inserted, into which molten steel is injected.