KR200444098Y1 - Tundish dam - Google Patents

Abstract

The present invention relates to a tundish dam installed inside the tundish to suppress the flow of molten steel moved from the ladle and the slag inflow into the casting position, more specifically, floating or containing in the molten steel in the ladle slag or tundish. The present invention relates to a tundish dam that prevents chemical damage due to tundish flux added to the tundish to effectively remove impurities.

The present invention is in the tundish dam 100 installed in the tundish to suppress the flow of molten steel moved from the ladle and the slag flow into the casting position,

An erosion resistant reinforcement 200 is provided on the tundish dam 100 where the slag line is formed to prevent chemical damage due to basic tundish flux.

Tundish, Dam, Flux, Continuous Casting, Slag

Description

Tundish dam

The present invention relates to a tundish dam installed inside the tundish to suppress the flow of molten steel moved from the ladle and the slag inflow into the casting position, more specifically, floating or containing in the molten steel in the ladle slag or tundish. The present invention relates to a tundish dam that prevents chemical damage due to tundish flux added to the tundish to effectively remove impurities.

As shown in FIG. 1, the continuous casting process, which is the final manufacturing process of the steelmaking process, is essentially required to pass the casting process of molten steel from the upper ladle 1 through the tundish 2 to the metal mold, and the tundish 2 The inside of the slit is turned to prevent the slag 1a in the ladle 1 from flowing into the metal mold 4 when molten steel is received from the ladle 1 through the shroud nozzle 3 into the tundish 2. The dish dam 10 is installed.

The tundish dam 10 is a disposable structure, and is manufactured in various types and shapes from as small as several tens of kilograms to as large as hundreds of kilograms depending on the width and height of the tundish 2.

At this time, the tundish flux 2a is used to effectively remove impurities contained in the molten steel suspended or contained in the ladle slag 1a or the tundish 2 introduced from the upper ladle 1.

Conventionally, a material such as rice hull was used to prevent heat and reoxidation of molten steel moved into the tundish 2 while effectively preventing the slag 1a from flowing into the tundish 2 from the ladle 1. In recent years, since the cleanliness of molten steel is required to produce high quality steels such as automotive interior and exterior materials and pipe steels, a highly basic tundish flux having a high content of calcium oxide (CaO) has been developed. It is used.

Highly basic tundish flux (2a) is usually composed of a composition having a melting point of about 1200 ~ 1300 ℃ lower than molten steel, and when injected into the upper surface of the initial casting molten melted from the upper surface of the molten metal within a few minutes to cover the surface of the molten steel and the outside air The contact of molten steel can be reduced. In addition, the highly basic tundish flux 2a reacts with magnesia (MgO) in the flux and alumina (Al ₂ O ₃ ) -based impurities, which are impurities in molten steel, to change to a low-melting non-solid state so that the purpose of flotation separation due to the difference in specific gravity is achieved. Also used as.

Since the conventional tundish dam 10 is made of alumina-based refractory material, the slag line part 11 in contact with the highly basic tundish flux 2a is chemically reacted and damaged. Is generated.

In particular, the tundish flux 2a is characterized by active chemical erosion in the vicinity of the molten steel temperature or in the temperature range lower than the molten steel temperature, the erosion phenomenon is mainly the upper portion of the tundish dam 10 along the slag line of the upper surface of the molten steel It is centered.

The present invention has been made in view of the above-mentioned conventional problems, and is a basic turn added in the tundish 2 to effectively remove impurities contained in or suspended in molten steel in the ladle (1) slag or tundish (2). It is an object of the present invention to provide a tundish dam 10 in which chemical damage due to the dish flux 2a is prevented.

In order to achieve the above object, the present invention is a tundish dam installed in the tundish to suppress the flow of molten steel moved from the ladle and the slag flow into the casting position, the slab line of the tundish dam is formed Erosion-resistant reinforcing material is provided on the top to prevent chemical damage due to basic tundish flux.

According to the tundish dam according to the present invention configured as described above, by providing a reinforcing material on the top of the tundish dam in which the slag line is formed, to effectively remove impurities contained in the molten steel in the ladle slag or tundish Preventing chemical damage to the tundish dam due to contact with the tundish flux added in the tundish has an effect of improving the life of the tundish dam.

In addition, the present invention is because the reinforcement is made in the form of a block or tile, it is very easy to respond to a variety of conditions, such as changing the operating time or composition of the tundish flux by adjusting the thickness, height, etc. of the block or tile It can work.

In addition, the present invention has the effect that the reinforcing material is provided only in the slag grain portion that is floated by the specific gravity difference during the casting operation, it is possible to improve the life of the tundish dam with only a small cost and a small weight increase.

Although the present invention has been illustrated and described in connection with specific embodiments, the present invention may be variously modified and changed without departing from the spirit or the field of the present invention provided by the following utility model registration claims. It should also be included in the scope of the present invention.

The features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments based on the accompanying drawings. Prior to this, terms or words used in the present specification and claims are defined in the technical spirit of the present invention based on the principle that the inventor can appropriately define the concept of the term in order to best describe his or her own design. It must be interpreted to mean meanings and concepts.

As shown in Figure 2 and 3, the tundish dam 100 of the present invention is installed inside the tundish to suppress the flow of molten steel moved from the ladle and the slag flow into the casting position.

The upper portion of the tundish dam 100 in which the slag line is formed is provided with an erosion resistant reinforcement 200 to prevent chemical damage due to basic tundish flux.

The reinforcement 200 is composed of at least one block 210 forming an upper portion of the tundish dam 100. In this case, it is preferable that the reinforcement 200 is firmly fixed through the fastening member 211 spirally fastened to the tundish dam 100 so as to prevent injuries in the molten steel.

Meanwhile, as shown in FIG. 4, the reinforcement 200 may be formed of at least one tile 220 attached to the upper surface of the tundish dam 100. In this case, it is preferable that the step 110 forming the attachment surface of the reinforcement 200 is formed on the upper portion of the tundish dam 100 so that the attachment is performed in a stable state at an accurate position. In this case, when the tiles 220 have a thickness sufficient to protrude from the surface of the dam body in the state attached to the step 110, it is possible to easily handle the tundish dam 100.

The reinforcement 200 according to the present invention may be manufactured after heat treatment by forming a composition powder such as a castable in the form of a block 210 or a tile 220 or molding a press such as a compression molding machine.

When the reinforcement 200 according to the present invention is composed of a plurality of blocks 210 or tiles 220, the blocks 210 or tiles 220 are coupled in the transverse direction. As shown in FIG. 5, the coupling surface 230 of the adjacent reinforcement 200 block 210 or the tiles 220 may be formed of an inclined surface or a curved surface or a tooth surface. This is to ensure that the bonding state of the block 210 or the tile 220 is made stable.

In addition, although not shown, when the reinforcement 200 is composed of a plurality of blocks 210 or tiles 220, to relieve the stress due to thermal expansion between the blocks 210 or between the tiles 220 at a high temperature of use temperature conditions. An expansion table such as mortar may be further provided.

According to the present invention, the reinforcing member 200 is made of at least one material of magnesia, zircon, zirconia or alumina.

Conventional Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7   Ingredient (%) Al ₂ O ₃ 60 75 85 30 - 5 3 - MgO - - - 50 75 80 90 - SiO ₂ 30 20 10 - - 5 3 30 ZrO ₂ - - - - - - - 65 C - - - 15 20 - - - Specific gravity (g / cc) 2.45 2.50 2.73 3.10 3.00 3.28 3.45 3.8 Thermal expansion rate (%, 1000 ℃) 0.5 0.6 0.8 0.7 1.0 1.0 1.2 0.45 Content Bad usually Good Good Very good Very good Best Very good

Table 1 is an experimental result of reactivity with calcium oxide in the vicinity of the molten steel temperature through an embodiment in which the reinforcing material was manufactured in various composition ratios to increase the chemical resistance near the molten steel temperature for the slag component containing a large amount of calcium oxide. .

Comparative Examples 1 and 2 are experimental results of the reinforcing material produced by increasing the alumina content as compared to the conventional reinforcing material, it can be seen that the chemical resistance is improved. However, these comparative examples are not suitable because the weight of the reinforcing material increases with the increase of the content of alumina and the disadvantages of the raw material cost increase.

As can be seen in Table 1, Comparative Examples 3 to 7 are experimental results of the reinforcing material prepared by containing a component of magnesia, zircon or zirconia having high temperature reactivity with calcium oxide, the materials used in the comparative examples Since the damage occurs by chemical reaction with calcium oxide in the vicinity of about 2300 ℃, much higher than the molten steel temperature, it can be seen that it has an excellent effect in terms of solvent resistance.

1 is a schematic diagram of a typical continuous casting process.

2 is a perspective view of a tundish dam according to the present invention.

3 is a longitudinal cross-sectional view of FIG. 2;

4 is a perspective view showing another embodiment of a tundish dam according to the present invention.

Figure 5 is a perspective view of a tundish dam according to the present invention, a view showing a combined state of the blocks or tiles constituting the tundish dam.

<Explanation of symbols for the main parts of the drawings>

100 ... Tundish Dam 110 ...

200 ... Reinforcement 210 ... Block

211.Tightening member 220 ... Tile

230 ... Mating surface

Claims (7)

In the tundish dam installed in the tundish to suppress the flow of molten steel moved from the ladle and the slag flow into the casting position, Tundish dam, characterized in that the corrosion resistance reinforcement for preventing the chemical damage caused by basic tundish flux on the top of the tundish dam is formed slag line. The method of claim 1, The reinforcement is a tundish dam, characterized in that at least one block forming an upper portion of the tundish dam. The method of claim 2, The reinforcement is a tundish dam, characterized in that firmly fixed through a fastening member that is screwed to the tundish dam. The method of claim 1, And the reinforcement is at least one tile attached to an upper surface of the tundish dam. The method of claim 4, wherein Tundish dam, characterized in that the stepped portion forming the attachment surface of the reinforcement on the top of the tundish dam. The method according to claim 2 or 4, When the reinforcement is composed of a plurality of blocks or tiles, the blocks or tiles are coupled in the transverse direction, the engaging surface of the adjacent block or tiles is a tundish dam, characterized in that consisting of the inclined surface or curved surface or tooth surface. The method of claim 1, The reinforcing material is a tundish dam, characterized in that made of at least one material of magnesia (MgO) or zircon (ZrSiO ₄ ) or zirconia (ZrO ₂ ) or alumina (Al ₂ O ₃ ).

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