JPH09314315A - Method for repairing tuyere refractory in molten metal vessel, and tuyere refractory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save the labor and period for demolishing and removing refractories and to reduce the amount of repairing refractories by demolishing only a tuyere without demolishing the refractory surrounding the tuyere and setting the tuyere having smaller shape than the demolished tuyere. SOLUTION: After demolishing and removing the originally used tuyere, the tuyere 4 for exchange which has smaller outer diameter (d) than the outer diameter D of the original tuyere, is fitted so as to coincide with the axial line of the tuyere in a ladle. After fitting the tuyere 4, monolithic refractory 5 is allowed to flow into gap between the tuyere 4 and lining refractory 3, and the worn part of the lining refractory 3. The size of the tuyere for fitting at the time of repairing, has the shape at smaller length of one side by 5-30% than that of the original tuyere in the case of being the square type tuyere, and at smaller outer diameter by 5-30% than that of the original tuyere in the case of being the round type tuyere.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for repairing a tuyere refractory of a molten metal container and a tuyere refractory.

[0002]

2. Description of the Related Art In a molten steel container such as a ladle and a tundish, a molten steel discharge port and a gas injection plug are provided at the bottom of the container, and a fire-resistant so-called tuyere (10 in FIG. 5) is provided at that portion. An object, an upper nozzle (11 in FIG. 5) and a gas blowing plug (12 in FIG. 5) are attached.

Refractory materials such as ladle and tundish are usually used several times, and then an intermediate repair is performed to replace the refractory material. In the intermediate repair, repair the part with large damage or replace the refractory lining.

As the refractory material at the bottom of the container, there are a case where bricks are constructed and a case where an irregular shaped refractory material is poured and constructed. In the case of a ladle with bricks installed, it is common to replace the entire brick during intermediate repair.

When an irregular refractory material is applied to the bottom, it is common to replace the tuyere and build up the irregular refractory material on the surface of the molten refractory material.

FIG. 6 schematically shows the condition of the tuyere refractory remaining during the intermediate repair. Tuyere 14 for intermediate repair
Partly dismantle the refractories 16 around the, replace the tuyere,
The dismantled part is filled with refractory again.

[0007]

DISCLOSURE OF THE INVENTION
Although it is carried out by a machine such as a breaker, the dismantling range is unnecessarily wide and the surrounding refractories are often damaged.

In addition, without disassembling surrounding refractories,
The method of disassembling only the tuyere and constructing the tuyere of the same shape is difficult to construct the joint around the tuyere, and the surrounding refractories are deformed during use, so the tuyere is specified. This is a difficult method that is difficult to enter.

[0009]

The present inventor has developed the present invention as a result of various examinations and experiments in order to solve the above-mentioned drawbacks of the conventional method, and the technical constitution of the present invention is as follows.
In a repair method for repairing or replacing a tuyere refractory such as a ladle, tundish, etc., after dismantling and removing the tuyere originally used, then a tuyere of a shape smaller than the tuyere is attached, and then the bottom refractory A method of repairing a tuyere refractory, which is characterized by filling an irregular shaped refractory in the space between and, in the case of a square tuyere with respect to the originally used tuyere size after dismantling. If the tuyere has a circular side, the outer diameter is 5
It consists of using tuyeres that are 30% smaller. Furthermore, inside the bottom refractory such as ladle and tundish, there is a repair tuyer whose outer diameter or side is 5-30% smaller than the original tuyeres. A repaired tuyere refractory such as a ladle, tundish, etc. characterized by being installed through a construction layer consisting of an irregular shaped refractory for repair, and by having such a technical configuration, INDUSTRIAL APPLICABILITY The present invention performs the tuyere replacement without disassembling the refractory around the tuyere at the time of intermediate repair of the ladle, saves labor for dismantling the refractory, and reduces the amount of the refractory used for repair. Can be achieved.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, the method for repairing a tuyere according to the present invention is such that the refractory around the tuyere is not dismantled, only the tuyere is dismantled, and the shape of the tuyere is smaller than the dismantled tuyere. Is applied to fill the voids between the tuyere and the surrounding refractory material with the irregular-shaped refractory material. By adopting this method, it is not necessary to dismantle the surrounding refractory lining, and the labor of dismantling can be saved. Moreover, the surrounding refractory material is not damaged by the disassembly.

A method of repairing a tuyere refractory of the present invention will be described with reference to FIGS.
The details will be described with reference to the specific example shown in FIG.

FIG. 1 is a vertical cross-sectional view showing a damaged state of a tuyere and a refractory material around the tuyere, 2 is a remaining portion of the tuyere after use, and 3 is a remaining refractory material of an inner lining surrounding a tuyere brick. FIG. 3 is a vertical cross-sectional view showing the surfaces, and the broken line portions above them show the positions of the peripheral refractory and the tuyere at the start of use.

At the time of intermediate repair, first, only the tuyere 2 after use is disassembled. The refractory material of the tuyere is generally an alumina refractory, an alumina-carbon refractory, zircon, or the like, and a brick or an unshaped refractory precast product is used.

FIG. 2 shows a vertical cross-sectional view of the tuyere repaired by the method of the present invention. As described above, after the tuyere 2 is disassembled, the outer diameter d is smaller than the outer diameter D of the original tuyere 1. Replacement tuyere 4
Fit the ladle in line with the tuyere axis.

After mounting the tuyere 4, the irregular refractory 5 is applied between the tuyere 4 and the refractory lining 3 and on the worn portion of the refractory 3 lining. As the irregular refractory material, any method of pouring construction and stamp construction can be used. As the material, refractory materials such as alumina, alumina / spinel, alumina / magnesia, and zircon can be used. The same material as the original tuyere may be used, or a different material may be used.

The size of the tuyere to be constructed at the time of repair is such that a square tuyere has a side length of 5 to 30% smaller than the original tuyere, and a round tuyere has an outer diameter. The optimum shape is 5-30% smaller than the outer diameter of the original tuyere. If the size is about the same as the original shape, the construction becomes difficult, and if it is too small than the original shape, the durability of the tuyere becomes poor.

FIGS. 3 and 4 show a longitudinal cross-sectional view and a plan view of a main part of a circular tuyere after repair. Initially, a tuyere 6 having an outer diameter of D = 500 mm is constructed and operated up to the service limit of the tuyere 6. At the time of intermediate repair after being used, the initial tuyere was dismantled and removed, and then a small tuyere with an outer diameter of d = 400 mm was constructed, and an alumina / spinel amorphous refractory 8 was poured into the void around it. It was constructed.

[0018]

As described above in detail, according to the repairing method of the present invention, at the time of the intermediate repair of the ladle, the tuyere is replaced without disassembling and removing the refractory lining around the tuyere and refractory. The economic effect is to save labor and time for dismantling and removal, and to reduce the amount of refractory material used for repair.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a damaged state of a tuyere and a refractory material around the tuyere.

FIG. 2 is a longitudinal sectional view of a tuyere repaired by the method of the present invention.

FIG. 3 is a vertical cross-sectional view of the main part after repairing the circular tuyere.

FIG. 4 is a plan view of an essential part of FIG.

FIG. 5 is a vertical sectional view of a conventional tundish.

FIG. 6 is a vertical cross-sectional view showing the state of refractory remaining during intermediate repair.

[Explanation of symbols]

 1 Damaged part of tuyere 2 Remaining part of tuyere refractory after use 3 Lined refractory 4 Tuyere for replacement 5 Unshaped refractory 9 Molten steel container 10 Tuyere refractory 11 Upper nozzle 12 Gas injection plug 13 Before use Tuyere refractory 14 Tuyere refractory after use 15 Lined refractory 16 Dismantled part of lined refractory

Claims (3)

[Claims] 1. In a repair method for repairing or replacing a tuyere refractory of a container having a molten metal discharge port such as a ladle and a tundish, the tuyere originally used is dismantled and removed, and then the tuyere is used. A method for repairing a tuyere refractory, which comprises installing a tuyere having a smaller shape and filling a void with the refractory at the bottom with an irregular shaped refractory. 2. The size of the tuyere refractory to be mounted after dismantling is smaller than that of the originally used tuyere refractory, if the tuyere is square, one side thereof is, and if the tuyere is circular, the outer diameter is 5 to 30. %. The tuyere refractory repair method of claim 1 comprising using a smaller tuyere. 3. A construction in which a repairing tuyere whose outer diameter or one side is 5 to 30% smaller than the original tuyere is formed inside the bottom refractory material such as a ladle, tundish, etc. Tuyere refractories such as ladle, tundish, etc. characterized by being installed through layers.