JP2004255433A - Slide gate plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slide gate plate equipped with an inert gas blowing mechanism, which can effectively prevent the leakage of the inert gas and can be manufactured simply at a low cost. <P>SOLUTION: In the slide gate plate equipped with the mechanism which blows the inert gas into a molten metal tap hole 4 from a plurality of gas outlets 6 formed in a gas channel ring 5, a refractory ring 8 is put in a ring type channel formed in a contact surface between the bottom face of the gas channel ring 5 and the plate body 1, and mortar 3 bonds and fixes the bottom face of the gas channel ring 5, the refractory ring 8 and the plate body 1 together. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a slide gate plate, and more particularly, to a slide gate plate having a structure in which an inert gas is blown through a gas channel ring to prevent nozzle blockage.
[0002]
[Prior art]
A slide gate controls the amount of molten metal flowing out of a molten metal from a molten metal container such as a ladle or a tundish in the steelmaking or casting process. Since processing and continuous casting are becoming common, it is an indispensable member.
[0003]
The slide gate is installed at the bottom of the molten metal container, and a middle plate made of a refractory having a similar molten metal outlet is provided between an upper plate and a lower plate made of a refractory having a molten metal outlet. The three-plate type is generally used.
In the slide gate having such a configuration, the amount of molten metal flowing out is controlled by sliding the middle plate to change the opening area of the molten metal outlet.
[0004]
However, the refractory is in contact with the joint of the slide gate plate or the sliding surface of each plate, and when the molten metal flows out, outside air is drawn in from the gap in this portion, and oxides are generated in the molten metal. Or the drift of the molten metal causes a blockage of the nozzle by deposits and a deterioration in the quality of steel products due to alumina inclusions and the like.
[0005]
For this reason, in order to prevent the nozzle clogging and the formation and adhesion of alumina inclusions as described above, a method of blowing out a molten metal while blowing an inert gas such as argon or nitrogen has been proposed (eg, And Patent Document 1).
[0006]
FIG. 2 shows an example of a slide gate plate provided with an inert gas blowing means. The slide gate plate shown in FIG. 2 is an upper plate, and a steel shell 17 is shrink-fitted on a side peripheral portion of the plate main body 11, and a gas introduction pipe 12 communicating from the side peripheral portion toward the center is provided. It is adhesively fixed by a mortar 13.
Further, a gas channel ring 15 having a plurality of gas outlets 16 communicating with a molten metal outlet 14 is fitted through a mortar 13 on the inner peripheral surface of the opening of the dowel portion (convex portion) 11 a of the plate. Bonded. A gas reservoir 20 is formed in the lower peripheral portion of the gas channel ring 15 between the plate main body 11 and the concentric cylindrical gas reservoir 20 with the molten metal outlet 14.
In the slide gate plate configured as described above, the inert gas supplied from the gas introduction pipe 12 is blown into the molten metal outlet 14 from the gas outlet 16 via the gas reservoir 20. It is.
[0007]
Also, a slide gate plate configured to blow an inert gas using a porous refractory instead of the gas channel ring 15 has been proposed (for example, see Patent Document 2). FIG. 3 shows an example of such a slide gate plate.
[0008]
The slide gate plate shown in FIG. 3 is provided with a steel shell 17 and a gas introduction pipe 12 similarly to FIG. The periphery of the molten metal outlet 14 is made of a porous refractory 18, and a metal case 19 is provided in an outer peripheral area thereof, and a gas reservoir 20 is formed between them. Further, the metal case 19 is bonded and fixed by a mortar 13 filled in a gap in an outer peripheral portion thereof.
In the slide gate plate having such a configuration, the inert gas is supplied through the gas introduction pipe 12, passes through the gas reservoir 20, passes through the porous refractory 18, and flows into the molten metal outlet 14. It is blown.
[0009]
As described above, the joints of the respective members in the slide gate plate are bonded and fixed with mortar to secure airtightness in the gas storage chamber and the like, thereby preventing leakage of the inert gas.
[0010]
[Patent Document 1]
JP-A-62-43655 [Patent Document 2]
Japanese Patent Publication No. 6-5013
[Problems to be solved by the invention]
However, in order to obtain the effect of preventing the leakage of the inert gas, it has been very difficult to adjust the amount of the mortar used.
That is, in the slide gate plate as shown in FIG. 2, the surface to be bonded by mortar is very narrow, so it is difficult to sufficiently suppress the generation and expansion of cracks. When a large amount of mortar is used, there is a concern that excess mortar may protrude into the gas reservoir and block the gas introduction pipe, the gas outlet, and the like.
On the other hand, when the amount of the mortar used was small, the adhesion was insufficient, and a sufficient effect of preventing leakage of the inert gas could not be expected.
[0012]
Conversely, in the slide gate plate having the configuration shown in FIG. 3, the contact area between the metal case 19 and the mortar 13 is large, but in this case, the difference in the thermal expansion coefficient between the metal case 19 and the mortar 13 is large. There is a possibility that the metal case 19 is deformed due to thermal stress, and the boundary between the porous refractory 18 and the mortar 13 is peeled off.
[0013]
Further, in order to manufacture this slide gate plate, a process such as a perforation process and a welding process for passing the gas introduction pipe 12 through the metal case 19 was also required, which required time and cost in manufacturing.
[0014]
The present invention has been made to solve the above technical problem, and in a slide gate plate having an inert gas blowing mechanism, leakage of an inert gas can be effectively prevented, and It is an object of the present invention to provide a slide gate plate that can be manufactured easily and at low cost.
[0015]
[Means for Solving the Problems]
The slide gate plate according to the present invention is a slide gate plate provided with a mechanism for blowing an inert gas from a plurality of gas outlets formed in the gas channel ring to the molten metal outlet, wherein the gas channel ring bottom surface and the plate A refractory ring is inserted into a ring-shaped groove formed on a contact surface with the main body, and the gas channel ring bottom surface, the refractory ring, and the plate main body are bonded and fixed via a mortar. And
With the inside of the slide gate plate having such a configuration, even if the bonding area of the gas channel ring and the slide gate plate main body by the mortar is small, leakage of the inert gas can be reliably prevented.
[0016]
The refractory ring is preferably made of metal or dense ceramic.
By forming the refractory ring, which is a member to be inserted into the inside of the slide gate plate, from a heat-resistant material having no air permeability as described above, leakage of the inert gas can be effectively prevented.
[0017]
Preferably, the refractory ring has a thickness of 1 mm or less and a height of 3 mm or more.
Viewpoints to sufficiently prevent mortar peeling and deformation of the slide gate plate due to thermal stress during use, and to prevent leakage of inert gas at the joint between the gas channel ring bottom and the plate body by inserting the refractory ring. Therefore, it is preferable that the dimensions of the refractory ring be in the above range.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to the drawings.
The slide gate plate according to the present invention is a slide gate plate provided with a mechanism for blowing an inert gas from a plurality of gas outlets formed in the gas channel ring to the molten metal outlet, wherein the gas channel ring bottom surface and the plate A refractory ring is inserted into a ring-shaped groove formed on a contact surface with the main body, and the bottom surface of the gas channel ring, the refractory ring, and the plate main body are bonded and fixed via a mortar. .
By inserting the refractory ring into the slide gate plate in this way, even if the area of the mortar between the gas channel ring and the slide gate plate main body is small, leakage of the inert gas from the bonding surface is ensured. Can be prevented.
[0019]
FIG. 1 schematically shows a configuration of a slide gate plate according to the present invention.
The slide gate plate shown in FIG. 1 is an upper plate, and a steel shell 7 is shrink-fitted on a side peripheral portion of the plate main body 1, and a gas introduction pipe 2 leading from the side peripheral portion toward the center is provided with: It is adhesively fixed by a mortar 3.
A gas channel ring 5 formed with a plurality of gas outlets 6 communicating with a molten metal outlet 4 is formed on the inner peripheral surface of the opening of the dowel portion (convex portion) 1 a of the plate via a mortar 3. Fitted and bonded. In the lower peripheral portion of the gas channel ring 5, a gas storage chamber 10 concentric with the molten metal outlet 4 is formed between the gas channel ring 5 and the plate body 1.
A concentric ring-shaped groove is formed on the contact surface between the bottom surface of the gas channel ring 5 and the plate body 1, and a refractory ring 8 is inserted into the groove. The bottom surface of the gas channel ring 5, the refractory ring 8 and the plate body 1 are bonded and fixed via a mortar 3.
[0020]
In the slide gate plate having the above configuration, the inert gas supplied from the gas inlet pipe 2 is blown into the molten metal outlet 4 from the gas outlet 6 via the gas reservoir 10. It is.
[0021]
The gas channel ring 5 prevents the inert gas from leaking from the upper surface of the dowel portion 1a of the slide gate plate, and allows the inert gas to be melted from the gas outlet 6 without impurities being mixed into the molten metal. In order to ensure that the metal is blown into the metal outlet 4, it is preferable to use a dense refractory having a porosity of 10% or less.
As the material of the refractory, ceramics such as alumina, zirconia, silicon carbide, silicon nitride, and silica are preferably used.
[0022]
The bottom of the gas channel ring 5 for inserting the refractory ring 8 and the groove of the plate body 1 may be formed when the gas channel ring 5 and the plate body 1 are formed.
Alternatively, it may be formed by boring after performing impregnation treatment such as tar pitch. If the groove is formed by boring, the surface fired film, the impregnated material, and the like are removed, the familiarity with the mortar 3 is improved, and the adhesive strength can be further improved.
[0023]
The size of the diameter of the refractory ring 8 is not particularly limited, and can be appropriately changed according to the size of the slide gate plate to be used.
However, the thickness of the refractory ring 8 is preferably 1 mm or less.
If the thickness exceeds 1 mm, it becomes difficult for the mortar 3 filled in the surroundings to sufficiently absorb the thermal expansion of the refractory ring 8, and the mortar 3 peels off the joints and slide gates due to thermal stress. This causes deformation of the plate.
[0024]
The height of the refractory ring 8 is preferably 3 mm or more.
When the height is less than 3 mm, the effect of preventing the inert gas from leaking at the joint between the bottom of the gas channel ring 5 and the plate body 1 due to the insertion of the refractory ring 8 cannot be sufficiently obtained.
[0025]
The material of the refractory ring 8 may be any of metal and dense ceramics, and may be used without any particular limitation as long as it is a heat-resistant material having no air permeability. For example, in the case of metal, stainless steel, titanium or the like can be used, and in the case of dense ceramics, similarly to the channel ring, alumina, zirconia, silicon carbide, silicon nitride, silica, etc. Ceramics having excellent heat resistance such as quality can be used.
[0026]
In the case of a refractory ring made of metal, there is an advantage that it is easier to manufacture and can be manufactured at low cost.
On the other hand, in the case of a refractory ring made of dense ceramics, since the plate body 1 is usually also made of a heat-resistant ceramic, a ceramic material having a close thermal expansion coefficient is selected and used according to the material of the plate 1 body. By doing so, there is an advantage that deformation due to thermal stress, separation at a joint portion, and the like can be prevented.
[0027]
【The invention's effect】
INDUSTRIAL APPLICABILITY As described above, according to the present invention, in a slide gate plate provided with an inert gas blowing mechanism, even if the adhesive area of the mortar between the gas channel ring and the slide gate plate main body is small, leakage of the inert gas can be reduced. Can be prevented.
Moreover, the slide gate plate according to the present invention can be manufactured easily and at low cost.
Therefore, by using the slide gate plate according to the present invention, it is possible to prevent the nozzle from being clogged by deposits at the time of casting and to suppress deterioration in the quality of steel products due to alumina inclusions and the like, and, as a result, to improve production efficiency. It can also contribute to improvement and reduction of production costs.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view of a slide gate plate according to the present invention.
FIG. 2 is a schematic sectional view showing an example of a conventional slide gate plate.
FIG. 3 is a schematic sectional view showing an example of a conventional slide gate plate.
[Explanation of symbols]
1, 11 Plate body 1a, 11a Dowel part 2, 12 Gas introduction pipe 3, 13 Mortar 4, 14 Molten metal outlet 5, 15 Gas channel ring 6, 16 Gas outlet 7, 17, Iron shell 8, Refractory ring 10, Reference Signs List 20 Gas reservoir 18 Porous refractory 19 Metal case

Claims (3)

A slide gate plate having a mechanism for blowing an inert gas from a plurality of gas outlets formed in a gas channel ring to a molten metal outlet,
A refractory ring is inserted into a ring-shaped groove formed on the contact surface between the gas channel ring bottom surface and the plate body, and the gas channel ring bottom surface, the refractory ring and the plate body are bonded via a mortar. A slide gate plate which is fixed. The slide gate plate according to claim 1, wherein the refractory ring is made of metal or dense ceramic. The slide gate plate according to claim 1, wherein the refractory ring has a thickness of 1 mm or less and a height of 3 mm or more. 4.

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