JP2003205360A - Tuyere refractory structure - Google Patents

Abstract

(57) [Problem] To provide a refractory structure in which exposed portions of joints are not directly hit during oxygen cleaning of a container tuyere. SOLUTION: This is a refractory structure of a tuyere located at the bottom of a molten metal container and through which molten metal flows out, the upper nozzle 4 forming the outflow hole and the tuyere brick 3 forming the periphery thereof. A tuyere refractory structure comprising an upper nozzle protection refractory 5 positioned to cover a joint located at a boundary. The upper nozzle protection refractory may be formed integrally with the tuyere brick.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refractory structure around a tuyere for discharging molten metal in a molten metal container.

[0002]

2. Description of the Related Art At the bottom of a molten metal container 1 such as a ladle and a tundish, a tuyere 2 for discharging molten metal is provided as shown in FIG. Its tuyere 2
In the structure of FIG. 3, the tuyere brick 3 constructed in the container is conventionally provided as shown in FIG. 3B, and the upper nozzle 4 coated with mortar is inserted and fixed from below the tuyere brick 3. There is.

Since the upper nozzle consumes more severely than the tuyere brick, only the upper nozzle was removed by a means such as punching and replaced with a new upper nozzle when the tundish after casting was serviced. Conventionally, the upper end of the joint of mortar filling the gap between the upper nozzle and the tuyere brick has been exposed.

[0004]

When a tundish (hereinafter referred to as TD) is hot-maintained, when the previously cast residual hot water or the residual slag is discharged, the hot water drop part of the upper nozzle and its surroundings. It is necessary to clean the oxygen with oxygen to promote the outflow of the residual hot water and prevent the nozzle from being blocked. The mortar used for joints has lower heat resistance than upper nozzles or tuyere bricks, and the joints will be damaged if directly hit during oxygen cleaning.

Normally, this cleaning work is carried out manually by using a lance pipe or the like. However, there is a height difference of about 3 m between the operator's viewpoint and the periphery of the upper nozzle, and the precision of guiding the tip of the lance pipe to a target position. Is limited. In addition, during the actual cleaning work, the residual hot water and residue cover the surface, making it difficult to directly check the position of the joint. For this reason, there is a limit in reliably preventing the direct hit of the joint during the oxygen cleaning.
If the joint is damaged, the molten steel sealing property at the boundary between the upper nozzle and the tuyere brick will be problematic, and there have been cases where the hot use was abandoned.

An object of the present invention is to provide a refractory structure in which the exposed portion of the joint is not directly hit when the tuyere of the molten metal container is cleaned with oxygen.

[0007]

SUMMARY OF THE INVENTION The gist of the present invention is a refractory structure of tuyere at the bottom of a molten metal container for letting out molten metal. A tuyere refractory structure characterized by comprising a tuyere brick to be formed and an upper nozzle protective refractory positioned so as to cover joints located at the boundary between the upper nozzle and the tuyere brick, the upper nozzle A tuyere refractory structure, characterized in that a protective refractory material is integrated with the tuyere brick.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, the invention of claim 1 is such that the height of the upper nozzle 4 is made lower than in the prior art, and the upper nozzle 4 and the tuyere brick 3 are seen on it in plan view. A ring-shaped upper nozzle protection refractory that covers the joint of the boundary with (
The protective ring 5) is installed. In addition,
The protection ring 5 is not particularly limited to a ring shape, and may have another shape as long as it can cover the joint.

In order to make the outflow of the molten metal of the TD smooth, the protective ring 5 preferably has an inner inclination angle that matches the upper inclination of the inner surface of the upper nozzle 4. The space between the lower surface of the protective ring 5 and the upper portion of the upper nozzle may be filled with mortar or the like, but there is no problem even if voids are present, and when the molten metal is put in the container, the protective ring is not present. It is enough that the 5 is attached so that it does not rise. The material of the protection ring 5 does not have to be special, and there is no problem if the same material as the tuyere is used.

The second aspect of the present invention is, as shown in FIG. 2, the protection ring integrated with the upper portion of the tuyere brick 3 to form a protection ring-integrated tuyere brick 15. With such a structure, there is an advantage that the above-mentioned problem of floating of the protection ring can be solved and labor for construction can be saved.

[0011]

EFFECT OF THE INVENTION In the conventional tuyere structure, about 4 units / month of TD which cannot be used thereafter have been generated due to joint damage due to hot oxygen cleaning. With the application of the refractory structure, the joint damage was eliminated, and the above-mentioned situation of being unusable disappeared.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a first invention of the present invention.

FIG. 2 is a diagram showing an embodiment of the second invention of the present invention.

3A and 3B are views showing a conventional refractory structure, in which FIG. 3A is a sectional view of a tundish, and FIG. 3B is an enlarged detailed view of a portion A of FIG.

[Explanation of symbols]

1 molten metal container 2 tuyere 3 tuyere brick 4 upper nozzle 5 protection ring 15 Tuyere brick with integrated protection ring

Claims (2)

[Claims] 1. A refractory structure of tuyere at the bottom of a molten metal container for letting out molten metal, wherein an upper nozzle forming the outflow hole and a tuyere brick forming the periphery thereof,
A tuyere refractory structure comprising an upper nozzle protection refractory positioned so as to cover a joint located at a boundary between the upper nozzle and a tuyere brick. 2. The tuyere refractory structure according to claim 1, wherein the upper nozzle protection refractory is integrated with the tuyere brick.