JPH0630834Y2 - Gas blown tuyere structure for molten metal containers - Google Patents

Description

TECHNICAL FIELD The present invention relates to a gas blowing tuyere structure for a molten metal container.

Description of the Related Art Recently, an upper bottom blown converter steelmaking process in an electric furnace, and disposed gas blowing nozzle refining gas into the furnace bottom, oxygen from the gas blowing nozzle, CO, CO _2, hydrocarbons, unsaturated It has been found that the refining effect can be enhanced by forcibly stirring the molten metal by blowing an active gas or the like, and it is successively carried out.

However, when the refining gas is blown as described above, as the refining progresses, the gas blowing nozzle and the surrounding refractories are severely worn by the forced stirring of the molten steel and the slag, and the gas blowing nozzle The service life determines the service life of the entire molten metal container. Therefore, if the gas blowing nozzle can be replaced during use, the life of the entire molten metal container can be extended and a great economic effect can be obtained.

However, the conventional gas blowing nozzle has a structure in which the gas blowing nozzle is directly surrounded by tuyere bricks. Therefore, since the gas injection nozzle is in direct contact with the tuyere brick, the molten metal permeates into the joint between the tuyere brick and the gas injection nozzle and solidifies to adhere to the gas injection nozzle. It was very difficult to remove and replace only. In addition, since the tuyere brick is tapered in the vertical direction and is completely surrounded by the refractory material around the tuyere brick, it was very difficult to replace the tuyere brick. Furthermore, if the tuyere bricks around the gas blowing nozzle are significantly melted, even if the gas blowing nozzle is replaced, the tip of the new gas blowing nozzle will pop out, which is easily damaged by heat spalling. The effect of replacing the gas blowing nozzle could not be fully exerted.

Means for Solving the Problems The present invention has been made in view of the above points, and in order to solve the above problems, a molten metal container in which a gas blowing nozzle is attached and gas is blown to refine molten metal. In the gas blowing tuyere, the fixed shape refractory bricks are divided into a plurality of stages on the outer peripheral portion of the gas blowing nozzle, and the fixed shape refractory bricks are provided around the fixed shape refractory layer. Another object of the present invention is to provide a gas-blowing tuyere structure for a molten metal container, characterized in that a second fixed-shape refractory brick is divided into a plurality of stages around the outer periphery of the brick, and the refractory brick is circumferentially provided.

Effect According to the present invention, the first shaped refractory brick is divided into a plurality of stages on the outer side of the gas injection nozzle, and the irregular shaped refractory layer is provided around the irregular shaped refractory layer. The gas injection nozzle can be easily removed by breaking the gas injection nozzle, the gas injection nozzle can be replaced, and the upper part of the constant shape refractory brick can be partially replaced according to the melting loss. it can. In addition, the second fixed refractory brick is divided into a plurality of stages around the outer side of the first fixed refractory brick, and the tuyere brick portion of the constant refractory brick in the immediate vicinity of the gas injection nozzle is provided. Can also be replaced as appropriate, and the second fixed-form refractory brick can be partially replaced depending on the amount of erosion, and the durability of the molten metal container can be improved.

Embodiment Hereinafter, the present invention will be described based on an embodiment.

FIG. 1 and the following are embodiments of the present invention. As shown in FIG. 1, a gas injection nozzle 3 is attached to a furnace bottom portion 2 of a molten metal container 1 such as an electric furnace to provide a required gas supply device (not shown).
, And is arranged so that oxygen, CO, CO ₂ , hydrocarbons, inert gas, etc. can be blown in freely. As shown in the figure, the gas injection nozzle 3 is formed of a tapered columnar shaped refractory material having a slightly smaller diameter on the upper side, which is almost the same length as the thickness of the furnace bottom 2, and its central side. As shown in FIGS. 1 and 2, metal gas blowing pipes 4 are embedded in an annular shape at regular intervals. A gas reservoir 5 is provided at the bottom of the gas blowing nozzle 3, and the gas blowing pipe 4 is provided on the upper side thereof.
And the gas supply connection pipe 6 is joined to the lower side to connect to the gas supply device. Around the gas injection nozzle 3 thus formed, as shown in FIGS. 1 and 2, the first refractory brick blocks 7 are radially arranged in an annular shape at intervals of 10 to 100 mm. The formed first uniform refractory bricks 8 are installed in such a manner that they are divided into three stages and are joined together via a mortar 9, and the gas blowing nozzle 3 and the first uniform refractory bricks 8 are joined together. An amorphous refractory material such as castable is poured in between to form the first amorphous refractory layer 10. Further, as shown in the figure, the second constant refractory brick block 11 is formed by radially arranging second refractory brick blocks 11 in an annular shape around the periphery of the first constant shape refractory brick 8 as shown in the figure. The two fixed-size refractory bricks 12 are arranged so as to be joined in two or more stages, and the non-fixed-shape refractory material is provided between the first fixed-shape refractory brick 8 and the second fixed-shape refractory brick 12 in the same manner as above. The second amorphous refractory layer 13 is formed by pouring. 14 is a metal fitting for the gas injection nozzle 3, 15
Is the fixture above.

Then, for example, as shown in FIG.
When the upper side of the furnace is melted and needs to be replaced, the mounting hardware 14 on the bottom surface of the furnace bottom 2 is removed, the water cooling plate 16 is installed in the molten metal container 1, and the melted gas blown from above via the jig 17. As shown in FIG. 4, the insert nozzle 3 is hit by a hammer 18 or the like, or pulled from below by a hydraulic cylinder (not shown) or the like, and the inner peripheral portion of the first constant shape refractory brick 8 is cleaned. Insert a new gas injection nozzle 3 into
An amorphous refractory material such as castable is poured onto the outer peripheral portion of the gas blowing nozzle 3 to form it as shown in FIG.

Further, when the melting loss is so severe that 8 parts of the constant shape refractory brick are melted down and need to be repaired, after removing the gas blowing nozzle 3 as described above, the second irregular shape as shown in FIG. A pick 19 or the like is inserted into the refractory layer 13 and the first constant shape refractory brick 8 on the upper peripheral portion is peeled off. Then, as shown in FIG. 6, a new constant shape refractory brick 8 is joined via a mortar 9, a gas injection nozzle 3 is inserted, and an outer peripheral portion of the gas injection nozzle 3 and a constant shape refractory brick are inserted. Irregular shaped refractory materials are poured into the outer periphery of the brick 8 to repair it.

As described above, the gas blowing nozzle and the constant shape refractory brick can be easily replaced through the weakly shaped amorphous refractory layer arranged in a double shape in accordance with the melting damage state.

In particular, in this embodiment, since the first constant shape refractory brick is divided into three layers and laminated, the portion corresponding to the amount of erosion loss can be appropriately replaced, and the repair can be economically performed.

In the above embodiment, the first fixed refractory brick and the second fixed refractory brick are arranged in a circular ring shape, but they may be arranged in a polygonal ring shape.

Although the electric furnace has been described above, the present invention can be similarly applied to a molten metal container such as an upper bottom blowing converter.

As described above, according to the present invention, even if the gas injection nozzle or the fixed refractory bricks around it are melted, the irregular fire resistance poured into the outer periphery of the gas injection nozzle or the fixed refractory bricks. It is possible to easily replace and repair gas blow nozzles and surrounding fixed refractory bricks that have easily melted through the material layer. The two-dimensional refractory bricks can be partially replaced to extend the life of the molten metal container.

[Brief description of drawings]

1 and 2 are a side sectional view and a plan view of a gas blowing nozzle portion of a molten metal container according to an embodiment of the present invention, and FIGS. 3 and 4 are for explaining replacement of the gas blowing nozzle of the same. Side sectional views, FIG. 5 and FIG. 6 are side sectional views for explaining replacement of the above-mentioned standard refractory bricks. 1 ... Molten metal container, 2 ... Furnace bottom part, 3 ... Gas injection nozzle, 8 ... Constant refractory brick, 10 ... Irregular refractory layer, 12 ... Second regular refractory brick .

Front page continuation (72) Inventor Teruya Okuhashi 2 1576, Tohoku, Nakahiro, Ako-shi, Hyogo Prefecture Kawasaki Furnace Co., Ltd. (72) Inventor Hiroyuki Saito 1-5-1 Minato, Sendai City, Miyagi Prefecture No. Tohoku Steel Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. In a gas blowing tuyere structure for a molten metal container in which a gas blowing nozzle is attached to blow gas into a molten metal for refining molten metal, a first uniform refractory brick is provided on an outer peripheral portion of the gas blowing nozzle. It is divided into a plurality of stages and is provided around the irregular shaped refractory layer, and the second fixed type refractory brick is divided into a plurality of stages around the outer periphery of the first constant type refractory brick. A gas blowing tuyere structure for a molten metal container.