JPS61137657A - Tundish of continuous casting device - Google Patents

Abstract

PURPOSE:To provide a tundish of a continuous casting device which can maintain the uniform temp. distribution of a molten metal stored in the tundish by constituting the tundish in such a manner that the molten metal is stirred by a progressive magnetic field generator provided to the tundish. CONSTITUTION:The molten metal 3 poured from a pan 1 for the molten metal is once stored in a storage part 20 of the tundish and is poured through nozzles 23, 23 into a casting mold 4. Thrust is applied to the molten metal 3 stored in a storage part 20 by the progressive magnetic field generated by coils 29, 30, by which the molten metal is rotated along the inside wall of the part 20 and is thus stirred. Part of the coils 29, 30 are positioned in the bottom 20a and therefore the progressive magnetic field is generated near the bottom 25 so that the molten metal 3 is efficiently stirred from the bottom 25 as well. On the other hand, the molten metal 3 poured into the mold 4 is solidified from the periphery and is lowered in this state in the mold 4 so as to contact with a cooler 6, by which the ingot 7 is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a tundish for a continuous casting apparatus that can equalize the distribution of temperature changes in stored molten metal.

[Prior art]

Continuous casting equipment has the advantage of high production efficiency because it can produce products directly from molten metal.

Figure 6 is a schematic configuration diagram showing the configuration of the continuous casting device;
8 are a plan view and a sectional view taken along line 70A-A, respectively, showing the shape of a conventional tundish. In the figure, 1 is a molten metal pot and 2 is a tandish. The tundish 2 has two nozzles 2a, 2a on the bottom surface, and the molten metal 3 poured from the molten metal a1 flows into the tundish 2.
Each nozzle 2&, 2ak: an independent mold 4 is stored in the interior and connected via the nozzles 2a, 2&.
1C is injected from above. The molten metal 3 injected into the mold 4 is stirred by an in-mold stirrer (TA stirrer) 51C provided on the outer wall of the mold 4, and begins to solidify from the periphery within the bond 4 while component segregation is reduced. And the molten metal 3 is
While maintaining the shape inside the mold 4, it gradually descends inside the mold 4, emerges from below the mold 4, and touches the cooling device 6. Cooling water is constantly flowing into the cooling device 6, and the molten metal 3 is rapidly cooled to form the section 7, continues to descend, and is then held between the drawing straightening rollers 8, 8, while the advancing speed is adjusted. The direction of travel is gradually changed from vertically downward to horizontally. During this time, the secondary cooling zone stirrer (magnetic stirrer) 9 and the stirrer for the final stage of solidification ('ItL magnetic stirrer) IO
K, therefore, the unsolidified portion inside the slab 7 is stirred. The slab 7 moving in the horizontal direction is cut into appropriate lengths by a cutter 11 and transported by shell conveying rollers 12, 12, . . . . In addition, at the beginning of the work, a dummy bar (not shown) having a cross-sectional shape equal to the cross-sectional shape inside the mold 4 is applied from below to the bottom of the mold 4, and after blocking the outlet under the mold 4, the tundish 2 is closed. The molten metal 3 is injected into the mold 4. Then, the dummy bar is gradually lowered, and this is continued until the leading end of the slab 7 is held between the drawing straightening rollers 8.

After that, pull out the straightening roller 8.8 according to the degree of solidification progress.
By adjusting the rate of descent by ... and injecting molten dh3 into the mold 4 in accordance with the K, it is possible to continuously produce products.

[Problem that the invention seeks to solve]

By the way, during the work, the molten metal 3 stored in the tundish 2 is slightly distorted by the molten metal poured from the molten metal pot l and the molten metal coming out from the nozzles 2FL and 21L, but to this extent, the molten metal 3 stored in the tundish 2 is The molten metal 3 in 2 cannot be stirred sufficiently. For this reason, the temperature distribution of the molten metal 3 stored in the tundish 2Vc becomes non-uniform over time, resulting in a problem that casting irregularities occur in the product.

In view of the above-mentioned circumstances, an object of the present invention is to provide a tundish for a continuous casting apparatus that can equalize the temperature distribution of stored molten metal.

[Means to solve the problem]

In order to achieve the above object, the present invention is characterized in that the tundish is provided with a traveling magnetic field generating device to stir the molten metal stored in the tundish.

[Effect]

The molten metal stored in the tundish 2 is stirred by the rotating magnetic field generating device to make the temperature distribution uniform.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1, 2, and 3 are a plan view, a partially cutaway front view, and a side sectional view, respectively, showing the structure of a continuous casting device according to an embodiment of the present invention. be.

The tanditshu has a storage part 20 surrounded by front and rear walls 20a, 20a, left and right Q parts 20b, 20b, and bottom parts 20o and K. It is formed by a frame 22 that covers the outer periphery of the refractory material 21.

Further, both ends of the bottom portion 20c in the left and right direction are connected to the nozzle 2.
3.23 is formed and the outlet passage 24 in the nozzle 23.23
is open to the bottom 25 of the storage section 20.

The front and rear wall portions 20IL, 20a are slightly bent at both of their hooked portions (FIG. 1), and the horizontal cross section of the storage portion is octagonal. As a result, at the corners 26, 26, . Moreover, the front and rear walls 20a, 20a and the left and right walls 20b.

20bk each has a bent portion 27. at the central portion in the height direction.
28 is formed, and the width in the left-right direction and the front-back direction is constant in the upper part, while the width in the left-right direction and the front-rear direction gradually decreases toward the bottom part 20a. It becomes. Also, regarding the shape of the inside of the storage portion 20, below the bent portions 27, 28, the internal dimensions in the front-rear direction and the left-right direction gradually become smaller toward the bottom 25.

Inside the refractory material 21 of such a storage section 20, there is a wall section 20.
Two-phase coils 29 and 30 are embedded over all of a, 20 &, 20 b, and 20 b. That is, inside the refractory material 21, a coil 29 shown by a solid line and a coil 30 shown by a broken line in FIG. 4 are overlapped (embedded). These coils 29 and 30 each consist of one wire rod 3 and 32, and the wire rods 31 and 32 each have a different winding direction. The walls 20a, 20a of the reservoir 20 while alternately forming II and II,'Ml.

20b, going around the inside of 20b. In this case coil 2
9.30 is v - w, tl and X as shown in Figure 5.
-YAii! Odor [, 25K from the inner basket of the storage section 20 to the bottom]
It is bent at a predetermined angle 5 to match the shape of the wall, and the bent part at the -W line is located at the bent part 27 in the wall part 20& or the bent part 28 in the wall part 20b, A bent portion along the X-Y line is located at the boundary between the wall portion 20& and the bottom portion 20c or at the boundary between the wall portion 2(l) and the bottom portion 200.

As a result, a portion of the coils 29, 30 will be located inside the refractory material 21 forming the bottom portion 20a.

Further, the coil 29 and the coil 30 are overlapped with each other by half the width of the coil, and these coils /I/2
By supplying a current having a phase difference of 90° at 9.30°, a two-phase traveling magnetic field is generated that rotates the inner wall 11CG of the storage portion 20. A tundish having such a configuration is installed in place of the conventional tundish 2 in the continuous casting apparatus shown in FIG. 6 described above.

In the above configuration, the molten metal 3 into which the molten metal Ml has also been poured is temporarily stored inside the storage section 20 of the tundish and is injected into the mold 4 through the nozzles 23 and 23. During this time, the molten metal 3 stored in the storage section 20 is
A thrust is generated by the traveling magnetic field generated by the magnets 28 and 29, and the fluid rotates along the inner wall of the reservoir 20 and is stirred. In this case, since a part of the coils 29 and 30 are located in the bottom 200, the traveling magnetic field is generated near the bottom 25, and the molten metal 3 is efficiently flowed not only from the inner wall of the reservoir 20 but also from the bottom. When stirred well, it becomes thick. Furthermore, the fact that all the corners 26, 26, .

On the other hand, the molten metal 3 injected into the mold 4 solidifies from the periphery, descends inside the mold 4, and becomes a slab 7 when it comes into contact with the cooling device 6Vc. The slab 7 continues to descend further and is drawn to the straightening row 28.
Then, the traveling direction is gradually changed to the horizontal direction, and then the cutter 11 cuts it into an appropriate length.

〔Effect of the invention〕

As explained above, according to the present invention, the tundish is equipped with a traveling magnetic field generating device to stir the molten metal stored in the tundish, so that the temperature distribution and components of the molten metal are made uniform, and the product quality is improved. Quality improves.

[Brief explanation of drawings]

1, 2, and 5 are a plan view, a partially cutaway front view, and a side sectional view showing the configuration of a tundish according to an embodiment of the present invention, and FIG. 4 is a schematic diagram showing the arrangement of the coils. A plan view, FIG. 5 is a perspective view showing the arrangement of the coils, FIG. 6 is a schematic configuration diagram showing the configuration of the continuous casting device, and FIGS. 7 and 8 are each a configuration of a conventional tundish. FIG. 2 is a plan view and a cross-sectional view taken along line A-A of the same. 1... Hot water pot, 2a, 2a... Nozzle, 3... Bath water, 4... Mold, 23.2
3... Nozzle, 28° 29... Coil (traveling magnetic field generator). Figure 7 Figure 8

Claims (1)

[Claims] In a tundish of a continuous casting device that stores molten metal poured from a molten metal pot and injects the molten metal into a mold through a nozzle formed on the bottom surface, a traveling magnetic field generating means for stirring the stored molten metal is provided. A tundish of a continuous casting device characterized by comprising: