JP2973151B2 - Molten steel supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supply device for supplying molten steel to a continuous casting machine.

[0002]

2. Description of the Related Art In general, a continuous casting machine is provided with a mold, and a slab is drawn at a predetermined speed from a mold while supplying molten steel to the mold to continuously cast the slab. In a continuous casting machine, molten steel is supplied to a mold from a tundish. Then, molten steel is injected into the tundish from a ladle as an injection flow.

Meanwhile, inclusions mainly composed of oxides are generally mixed in the injection flow from the ladle, and in order to obtain high-quality slabs, that is, high-purity steel, the molten steel supplied to the mold is required. It is necessary to remove inclusions from the water.
Conventionally, in order to remove inclusions from molten steel, a filter is disposed in a tundish, and the inclusions are substantially removed by the filter.

Here, a conventional molten steel supply apparatus will be outlined with reference to FIG.

As shown in the figure, the molten steel supply device includes a tundish 11, and a molten steel supply port 11a is formed in the bottom surface of the tundish 11 near one end thereof (near the right end in the figure). A filter 13 is provided in the tundish 11 so as to divide the inside of the tundish into right and left. Ladle 1 above tundish 11
The injection flow is poured from the ladle 14 to the tundish 11. The molten steel poured into the tundish 11 flows through the inside of the tundish 11 as indicated by a solid line arrow, and is supplied to the mold 12 from a molten steel supply port 11a.

As described above, since the filter 13 is disposed at a position dividing the inside of the tundish into right and left, that is, since the filter 13 extends in a direction perpendicular to the flow of molten steel, the filter 13 The inclusions inside will be blocked. As a result, there is no inclusion in the molten steel supplied to the mold 12 from the molten steel supply port 11a. That is, inclusions can be removed from the molten steel supplied to the mold.

[0007]

By the way, in order to remove inclusions from molten steel using a filter, it is necessary to use a filter extending in a direction perpendicular to the flow of molten steel as described above. The area of the filter is naturally determined by the cross-sectional area of the tundish 11 and must be reduced.

Further, as shown in FIG. 6, inclusions accumulated in the filter increase exponentially with the passage of time. Considering that the molten steel (initial molten steel) at the start of continuous casting generally contains a large amount of inclusions, the time until the filter is clogged is short, and the operation must be stopped every time the filter is cleaned.

In addition, in the conventional molten steel supply device, since the molten steel flow only passes through the filter once, the inclusions are not sufficiently removed, and as a result, high clean steel cannot be obtained. .

[0010] It is an object of the present invention to provide a molten steel supply device capable of extending the time until the filter is clogged.

Another object of the present invention is to provide a molten steel supply device capable of sufficiently removing inclusions.

[0012]

According to the present invention, there is provided a molten steel supply device for use in a continuous casting machine having a mold for continuously supplying molten steel into the mold, wherein the molten steel supply device is provided at one end. A tundish that has a portion and has a molten steel supply portion at the other end, and the molten steel received by the molten steel receiving portion flows from the molten steel receiving portion toward the molten steel supply portion and is supplied from the molten steel supply portion to the mold; A filter disposed in the tundish and extending from the molten steel receiving portion to the molten steel supply portion; and applying a spiral motion to the molten steel around the direction from the molten steel receiving portion to the molten steel supply portion. A molten steel supply device characterized by having a spiral movement means is obtained.

Further, according to the present invention, there is provided a molten steel supply device used in a continuous casting machine having a mold for continuously supplying molten steel into the mold, the molten steel supply device having a molten steel receiving portion at one end. A tundish having a molten steel supply portion at the other end and flowing molten steel received by the molten steel receiving portion from the molten steel receiving portion toward the molten steel supply portion; and a tundish connected to the tundish at the molten steel supply portion and extending in a predetermined direction. A hot water supply gutter for providing the molten steel to the mold, a filter disposed in the hot water supply gutter and extending in the predetermined direction, and a spiral movement means for applying a spiral movement to the molten steel about the predetermined direction as an axis. Thus, a molten steel supply apparatus characterized by having the above is obtained.

[0014]

According to the present invention, the filter is arranged along the extending direction of the tundish or hot water supply gutter so as to impart a spiral movement to the molten steel, so that the molten steel flow passes through the filter a plurality of times. As a result, inclusions in the molten steel can be efficiently removed.

Further, as described above, since the filters are arranged along the extending direction of the tundish or the hot water supply gutter, the filter area can be increased, and as a result, the time until clogging can be increased. it can.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments.

Referring to FIG. 1, the molten steel supply device includes a tundish 11 extending in a predetermined direction, and a filter 21 extending in the above-described predetermined direction is provided in tundish 11. . That is, the filter 21 extending from the molten steel supply point in the direction of the molten steel supply port 11 a is disposed in the tundish 11.

The filter 2 is provided outside the tundish 11.
A pair of electromagnets 22 are arranged in parallel with 1, that is, along the above-mentioned predetermined direction.

As described above, the molten steel supplied from the ladle to the tundish 11 flows in the tundish 11 along the above-described predetermined direction, and is supplied to the mold from the molten steel supply port 11a. In the illustrated molten steel supply device, the electromagnet 22 is used.
Is supplied with an alternating current, which generates a rotating magnetic field. This rotating magnetic field is applied to molten steel flowing in the tundish 11 along a predetermined direction. By this rotating magnetic field, the molten steel flow is given a rotating motion about the above-mentioned predetermined direction as an axis.

Considering that the molten steel flows along a predetermined direction as described above, the molten steel performs a spiral motion as shown by a solid line arrow due to the addition of the rotational motion. As described above, the molten steel flow makes a spiral motion, so that the molten steel flow passes through the filter 21 a plurality of times, and the inclusions in the molten steel are captured by the filter 21 each time.

As described above, in the molten steel supply apparatus shown in FIG. 1, the filter is disposed along the extending direction of the tundish 11 so that the molten steel flows in the tundish 11 in the extending direction. , It is possible to improve the trapping rate of inclusions in the molten steel, as a result,
High purity steel can be provided.

In addition, in the molten steel supply device shown in FIG. 1, the filter is arranged along the direction in which the tundish 11 extends, so that the filter area can be increased (four to five times the conventional size). Therefore, as shown in FIG. 2, the time until the inclusion accumulation index reaches the filter clogging limit can be increased.

In FIG. 2, if the time until the operation stop in the conventional molten steel supply device is A minute and the time until the operation stop in the molten steel supply device shown in FIG. 1 is B minute, A / B
Is 3 to 4 times.

Although the filter 21 is arranged perpendicular to the bottom surface of the tundish 11 in the molten steel supply device shown in FIG. 1, the filter 21 is arranged parallel to the bottom surface of the tundish 11 as shown in FIG. You may make it.

Although the filter 21 is disposed in the tundish 11 in the molten steel supply device shown in FIG. 1, when the tundish 11 is hermetically sealed, the tundish 11 and the mold 12 are connected as shown in FIG. Fireproof hot water supply gutter 23
The filter 21 is disposed in parallel with the hot water supply gutter 23 along the axis of the hot water supply gutter 23 (that is, the flow direction of the molten steel), and the electromagnet 22 is arranged outside the hot water supply gutter 23. It may be. Here, the same components as those shown in FIG. 1 are denoted by the same reference numerals.

In the above-described embodiment, the molten steel flow is caused to spirally move by the electromagnet. For example, it is also possible to discharge argon gas into the molten steel, thereby giving irregular movement to the molten steel flow. Good.

[0027]

As described above, since the filter is arranged along the extending direction of the tundish or hot water supply gutter so as to give a spiral movement to the molten steel, the flow of the molten steel is repeated a plurality of times. And inclusions in the molten steel can be efficiently removed.

Further, since the filters are arranged along the extending direction of the tundish or the hot water supply gutter, the area of the filters can be freely selected, and the area of the filters can be increased as required. As a result, there is an effect that the time until clogging can be lengthened.

[Brief description of the drawings]

FIG. 1 (a) is a plan view for explaining one embodiment of a molten steel supply device according to the present invention, and FIG. 1 (b) is a cutaway elevational view showing one embodiment of the molten steel supply device according to the present invention. It is.

FIG. 2 is a diagram showing a relationship between the inclusion index in molten steel and the time in a molten steel supply device according to the present invention and a conventional molten steel supply device.

FIG. 3 is a view for explaining another example of a filter arrangement in the molten steel supply device according to the present invention.

FIG. 4A is an elevation view for explaining another embodiment of the molten steel supply device according to the present invention, and FIG. 4B is an elevational view of A in FIG.
FIG. 4 is a cross-sectional view taken along a line A.

FIG. 5 is a view for explaining one embodiment of a conventional molten steel supply device.

FIG. 6 is a graph showing the relationship between inclusion index in molten steel and time.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Tundish 12 Mold 13 Filter 14 Ladle 21 Filter 22 Electromagnet 23 Hot water supply gutter

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B22D 11/10 B22D 11/10 310 B22D 11/10 350 B22D 43/00

Claims (4)

(57) [Claims] 1. A molten steel supply device for use in a continuous casting machine having a mold, for continuously supplying molten steel into the mold, wherein the molten steel supply portion is provided at one end and the molten steel supply portion is provided at the other end. A tundish having the molten steel received by the molten steel receiving portion and flowing from the molten steel receiving portion toward the molten steel supply portion to supply the molten steel from the molten steel supply portion to the mold;
A filter disposed in the tundish and extending from the molten steel receiving portion to the molten steel supply portion; and applying a spiral motion to the molten steel around the direction from the molten steel receiving portion to the molten steel supply portion. A molten steel supply device, comprising: a spiral movement means. 2. The molten steel supply device according to claim 1, wherein the spiral movement means is an electromagnet arranged outside the tundish, and the electromagnet is supplied with an alternating current and generated by the electromagnet. A molten steel supply device characterized in that the spiral movement is given to the molten steel by a rotating magnetic field. 3. A molten steel supply device for use in a continuous casting machine equipped with a mold, for continuously supplying molten steel into the mold, wherein the molten steel supply portion is provided at one end and the molten steel supply portion is provided at the other end. A tundish for flowing molten steel received at the molten steel receiving portion from the molten steel receiving portion toward the molten steel supply portion, and a tundish connected to the tundish at the molten steel supply portion and extending in a predetermined direction to form the molten steel into the mold. Hot water supply gutter, a filter disposed in the hot water supply gutter and extending in the predetermined direction, and a spiral movement means for applying a spiral movement to the molten steel about the predetermined direction as an axis. Molten steel supply device. 4. The molten steel supply device according to claim 3, wherein the spiral movement means is an electromagnet arranged outside the hot water supply gutter, and an alternating current is applied to the electromagnet, and the electromagnet is generated by the electromagnet. A molten steel supply device characterized in that the spiral movement is given to the molten steel by a rotating magnetic field.