KR101175626B1

KR101175626B1 - Ladle and construction method of refractories for ladle

Info

Publication number: KR101175626B1
Application number: KR1020100073121A
Authority: KR
Inventors: 이만식; 강건용
Original assignee: 현대제철 주식회사
Priority date: 2010-07-29
Filing date: 2010-07-29
Publication date: 2012-08-21
Also published as: KR20120011385A

Abstract

The present invention is disposed on the first refractory and the concave portion, which is disposed on the bottom and the outer shell, which is formed on the wall and the bottom, and the one portion is formed more concave than the periphery, so as to form a receiving space of the molten steel, A method for constructing ladles and ladle refractories comprising a second refractory and a third refractory formed to cover the first refractory and the second refractory having different characteristics from the first refractory.

Description

LADLE AND CONSTRUCTION METHOD OF REFRACTORIES FOR LADLE}

The present invention relates to a ladle and ladle refractory construction method for receiving molten steel in a steelmaking furnace in a continuous casting process and supplying to the tundish.

In general, a continuous casting machine is a facility for producing slabs of a constant size by receiving a molten steel produced in a steelmaking furnace and transferred to a ladle in a tundish and then supplying it as a mold for a continuous casting machine.

The continuous casting machine includes a ladle for storing molten steel, a continuous casting machine mold for cooling the tundish and the molten steel discharged from the tundish to form a casting having a predetermined shape, and a casting formed in the mold connected to the mold. It includes a plurality of pinch roller to move.

In other words, the molten steel tapping out of the ladle and tundish is formed of a slab (Slab) or bloom (Bloom), billet (Billet), etc. having a predetermined width and thickness in the mold is transferred to the next process.

It is an object of the present invention to provide a ladle and ladle refractories construction method which can reduce the refractory dropout of unnecessary parts during the refractory replacement of the ladle bottom.

Ladle according to an embodiment of the present invention for realizing the above object is disposed on the bottom, and the outer shell, consisting of a wall and the bottom, to form a receiving space of the molten steel, a portion is formed in the recess than the periphery And a second refractory disposed on the first refractory and the concave portion, the second refractory having different characteristics from the first refractory and formed to cover the first refractory and the second refractory. have.

The concave portion may correspond to the center of the bottom, and may be formed on the first refractory.

The first refractory may include an amorphous refractory.

The first refractory may include a castable.

The second refractory may include a refractory lead.

The second refractory may include one having a greater impact resistance than the first refractory.

The second refractory may include an alumina material.

Ladle refractory construction method according to an embodiment of the present invention for realizing the above object is the step of building a permanent field on the bottom and the inner wall surface of the shell, and the first refractory on the permanent field corresponding to the floor Accumulating the second refractory, constructing a second refractory having a smaller area than the first refractory of the first refractory, and filling the first refractory around the second refractory in correspondence with the height of the second refractory; And putting the third refractory to cover the first and second refractory materials.

The first refractory may include an amorphous refractory.

The first refractory may include a castable.

The second refractory may include an alumina material.

According to the ladle and ladle refractory construction method according to the present invention configured as described above, when replacing the refractory of the ladle bottom, it is possible to reduce the falling off of the refractory of the unnecessary portion, there is an effect that the replacement operation is easy.

1 is a conceptual diagram for explaining a continuous casting machine mainly on the flow of molten steel (M).
2 is a cross-sectional view schematically showing the configuration of a ladle according to an embodiment of the present invention.
3 is a flowchart illustrating a ladle refractories construction method according to an embodiment of the present invention.
4A to 4E are schematic views illustrating a construction form sequentially according to the construction order to explain the ladle refractory construction method according to an embodiment of the present invention.

Hereinafter, a ladle and a ladle refractories construction method according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the present specification, different embodiments are given the same or similar reference numerals for the same or similar configurations, and the description thereof is replaced with the first description.

1 is a conceptual diagram for explaining a continuous casting machine mainly on the flow of molten steel (M).

Referring to this figure, the molten steel (M) is to flow to the tundish 20 in the state accommodated in the ladle (10). For this flow, the ladle 10 is provided with a shroud nozzle 15 extending toward the tundish 20. The shroud nozzle 15 extends to be immersed in the molten steel in the tundish 20 so that the molten steel M is not exposed to air and oxidized and nitrided. The case where molten steel M is exposed to air due to breakage of shroud nozzle 15 is called open casting.

The molten steel M in the tundish 20 flows into the mold 30 by a submerged entry nozzle 25 extending into the mold 30. The immersion nozzle 25 is disposed in the center of the mold 30 so that the flow of molten steel M discharged from both discharge ports of the immersion nozzle 25 can be symmetrical. The start, discharge speed, and stop of the discharge of the molten steel M through the immersion nozzle 25 are determined by a stopper 21 installed in the tundish 20 corresponding to the immersion nozzle 25. Specifically, the stopper 21 may be vertically moved along the same line as the immersion nozzle 25 to open and close the inlet of the immersion nozzle 25. Control of the flow of the molten steel M through the immersion nozzle 25 may use a slide gate method, which is different from the stopper method. The slide gate controls the discharge flow rate of the molten steel M through the immersion nozzle 25 while the sheet material slides in the horizontal direction in the tundish 20.

The molten steel M in the mold 30 starts to solidify from the part in contact with the wall surface of the mold 30. This is because heat is more likely to be lost by the mold 30 in which the periphery is cooled rather than the center of the molten steel M. The rear portion along the casting direction of the strand 80 is formed by the non-solidified molten steel 82 being wrapped around the solidified shell 81 in which the molten steel M is solidified by the method in which the peripheral portion first solidifies.

As the pinch roll 70 (FIG. 1) pulls the tip portion 83 of the fully solidified strand 80, the unsolidified molten steel 82 moves together with the solidified shell 81 in the casting direction. The uncondensed molten steel 82 is cooled by the spray 65 for spraying cooling water in the course of the above movement. This causes the thickness of the uncooled steel (82) in the strand (80) to gradually decrease. When the strand 80 reaches the solidification completion point 85, which is a point, the strand 80 is filled with the solidification shell 81 in its entire thickness. The solidified strand 80 is cut to a predetermined size at the cutting point 91 and divided into a product P such as a slab.

2 is a cross-sectional view schematically showing the configuration of a ladle 10 according to an embodiment of the present invention.

Referring to the figure, the ladle 10 may include a shell 100, a permanent field 200, a first refractory 300, a second refractory 400, and a third refractory 500. have.

The outer shell 100 forms an outer shape of the ladle 10. The outer shell 100 may be formed of a wall and a bottom to form a space that can accommodate the molten steel (M). The outer shell 100 may be made of a steel sheet or the like.

Permanent field 200 may be a refractory lead that is disposed along the inner surface of the shell (100). The permanent field 200 serves to protect the outer shell 100 as well as to prevent the molten steel M from flowing out due to the damage of the refractory further built into the permanent field 200. Therefore, it is desirable to be a heat resistant material that can withstand high temperatures. Permanent field 200 may be to be built on all of the bottom and the inner surface of the wall for the protection of the shell (100).

The first refractory 300 may be formed along the inner surface of the permanent field 200 disposed on the bottom of the ladle 10. The first refractory 300 serves to protect the permanent field 200 of the bottom. In addition, the first refractory 300 is to absorb the impact applied to the floor when the molten steel (M) is accommodated in the ladle (10). Therefore, the first refractory 300 may be a material having excellent impact resistance. The first refractory 300 may be formed of an amorphous refractory to be easily formed on the bottom of the ladle 10. Specifically, the first refractory 300 may be castable. The first refractory 300 may be formed with a portion 310 in which one portion is concave than the periphery. Specifically, the concave portion 310 may be formed at the upper end of the first refractory 300 corresponding to the bottom center.

The second refractory 400 may be disposed in the concave portion 310 of the first refractory 300. The second refractory 400 may serve to prevent the first refractory 300 from dropping out together during repair and replacement of the third refractory 500 in contact with the molten steel M. Specifically, the second refractory 400 may be a refractory soft wire that is constructed in the concave portion 310 of the upper end of the first refractory 300. In addition, the second refractory 400 may have different characteristics from the first refractory 300. The second refractory 400 may be a material having better impact resistance than the first refractory 300. For example, the second refractory 400 may be made of alumina.

The third refractory 500 may be disposed to cover the first refractory 300 and the second refractory 400. In addition, the third refractory 500 may be formed along the inner circumference of the wall to surround the wall. Specifically, the third refractories 500 surrounding the wall may be formed along the inner surface of the permanent field 200 formed on the wall. The third refractory 500 may be a refractory lead. In addition, the third refractory 500 may be a refractory soft wire that is constructed in a form in which the bottom and the wall portion are separated from each other. The third refractory 500 is in contact with the molten steel M while protecting the permanent field 200 of the wall, the first refractory 300 and the second refractory 400. Therefore, it is preferable that the third refractory 500 is a material having superior corrosion resistance and wear resistance than the permanent field 200, the first refractory 300, and the second refractory 400.

3 is a flowchart illustrating a ladle refractories construction method according to an embodiment of the present invention. 4A to 4E are schematic views illustrating the form of construction sequentially according to the construction order to explain the ladle refractory construction method according to an embodiment of the present invention.

Referring to the drawings, a ladle refractory building method according to an embodiment of the present invention will be described.

It may include the step (S10) to build a permanent field 200 on the bottom and the wall of the shell (100). The permanent field 200 may be a refractory lead having a large heat resistance, and may be generally constructed along the inner surface of the shell 100.

Next, a step (S20) of stacking the first refractory 300 to abut on the upper end of the permanent field 200 corresponding to the bottom. Stacking the first refractory 300, it may be a form to pour the first refractory 300 in the form of an amorphous refractory on the upper end of the permanent field 200 previously constructed. Specifically, the first refractory 300 may be castable.

Next, a step (S30) of constructing the second refractory 400 having a smaller area than the first refractory 300 on the top of the first refractory 300. Specifically, the second refractory 400 may be constructed in a circle having an area of a predetermined diameter starting from the center of the upper end of the first refractory 300. The second refractory 400 may be a material having a greater impact resistance than the first refractory 300. Specifically, the second refractory 400 may be made of alumina.

Next, a step (S40) of filling the first refractory 300 around the second refractory 400 may correspond to the height of the second refractory 400. The first refractory 300 is an amorphous refractory, and may be castable. Therefore, the castable may be poured around the second refractory 400 and hardened. The height of the castable may be equal to the height of the second refractory 300 constructed.

Finally, the method may include a step S50 of constructing the third refractory 500 to cover the first refractory 300 and the second refractory 400. The third refractory 500 is a refractory disposed at the innermost side of the ladle 10, and may be in the form of refractory lead. Therefore, the third refractory 500 is constructed on the wall in the form of enclosing the permanent field formed on the wall, and the third refractory 500 is formed on the bottom so as to cover both the first refractory 300 and the second refractory 400. It may be to build. The third refractory 500a constructed on the wall and the third refractory 500b constructed on the bottom may be separated from each other. The separated gap between the third refractory 500a constructed on the wall and the third refractory 500b constructed on the bottom may be filled by a castable.

Such ladle and ladle refractories construction method is not limited to the configuration and operation of the embodiments described above. The above embodiments may be configured such that various modifications may be made by selectively combining all or part of the embodiments.

10: ladle 15: shroud nozzle
20: tundish 21: stopper
25: immersion nozzle 30: mold
65: spray 70: pinch roll
80: strand 81: solidified shell
82: unsolidified molten steel 85: solidification completion point
91: cutting point 100: sheath
200: permanent field 300: first refractory
400: second refractory 500, 500a, 500b: third refractory
C: bottom center P: product

Claims

An outer shell, consisting of a wall and a floor, to form a receiving space for the molten steel;
A first refractory disposed on the bottom, wherein a portion of the first refractory is formed;
A second refractory disposed in said concave portion, said second refractory having different characteristics from said first refractory; And
A ladle comprising a third refractory formed to cover said first refractory and said second refractory.

The method of claim 1,
The concave portion,
A ladle corresponding to the center of the bottom, formed on top of the first refractory.

The method of claim 1,
The ladle, wherein the first refractory includes an amorphous refractory.

The method of claim 3, wherein
Ladle according to claim 1, wherein the first refractory is castable.

The method of claim 1,
And the second refractory includes refractory lead.

The method of claim 1,
The second refractory includes ladle having a greater impact resistance than the first refractory.

The method according to claim 6,
The second refractory includes a ladle, the ladle.

Constructing a permanent field at the bottom and inner wall of the shell;
Stacking a first refractory on a permanent field corresponding to the bottom;
Constructing a second refractory having a smaller area than the first refractory of the first refractory;
Filling the first refractory around the second refractory corresponding to the height of the second refractory; And
Constructing a third refractory to cover said first and second refractory.

The method of claim 8,
And the first refractory is an amorphous refractory.

The method of claim 9,
And the first refractory is castable.

The method of claim 8,
The second refractory includes ladle refractories having a greater impact resistance than the first refractory, ladle refractory building method.

12. The method of claim 11,
The second refractory material, alumina material, comprising a refractory construction method of the ladle.