JPH10219321A - Blast furnace mouth structure - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a furnace port structure capable of further extending the life of the furnace port with the recent technological progress of blast furnaces. SOLUTION: A heat-resistant and abrasion-resistant liner is detachably attached to a steel shell at least at a collision portion of a charged material at a mouth portion of a blast furnace, and a gap between the liner and the steel shell is provided. A cooling panel having a cooling function is arranged below the liner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can improve the internal structure of a blast furnace furnace opening, in particular, the durability of the blast furnace furnace opening, and can repair the damaged furnace to prolong the equipment life. And the structure of the blast furnace mouth.

[0002]

2. Description of the Related Art Raw material charged from the furnace top collides with the inner wall of a furnace wall of a blast furnace, and the charged raw material slides down the inner wall of the furnace wall, so that abrasion resistance is required. At the same time, since the furnace is exposed to a high-temperature gas having an average temperature of 300 to 400 ° C., heat resistance is also required.

Therefore, for example, as shown in FIG.
Through a support metal 3 fixed to a steel shell 1, a portion of the inner surface where a raw material 2 charged into a furnace from a furnace top charging device (not shown) such as a bell or a bellless chute collides,
A wear ring 4 made of wear-resistant material is installed,
Furthermore, a castable 5 is provided between the iron skin 1 and the wear ring 4.
A structure is adopted in which the steel shell 1 is protected by filling the steel.

[0004] However, in the blast furnace operation, an operation malfunction sometimes occurs, and for example, a high-temperature gas of 800 to 1000 ° C may reach from the furnace top to the furnace opening, and even if the heat ring is not heat-resistant. Since the temperature can exceed the temperature, the wear ring may be cracked, worn or peeled off during a long operation period of the blast furnace. As a result, the life of the blast furnace mouth is relatively short, about several years after operation. If the blast furnace mouth is damaged, the distribution of the charge in the furnace becomes unstable, the gas flow distribution in the furnace becomes inappropriate, and the ore reduction status is deteriorated, impeding productivity. In addition, a problem such as gas leakage or the like occurs due to thermal deformation or cracks in the iron shell itself at the furnace opening, resulting in a disadvantage that the life of the blast furnace itself is shortened.

Various measures have been devised to address the problem of the blast furnace opening. For example, JP-A-49-39503 and JP-A-61-9508 disclose a cooling water pipe in a wear ring (ore receiving metal). Is provided to cool the wear ring. That is, by cooling the wear ring, it is possible to prevent the wear ring from exceeding the heat-resistant temperature when the operation is malfunctioning, which is effective in extending the life of the furnace port.

[0006]

However, the raw material repeatedly hits each time the raw material is charged, and although it is said that the raw material is water-cooled, there are many occasions where the raw material is exposed to high-temperature gas. Unavoidable wear and damage to water-cooled piping. That is, the problem is that the life of the furnace mouth is particularly short as compared with other blast furnace parts. This is due to the prolongation of the life of the furnace body and incidental equipment accompanying the recent technological advancement. With a life span of over 10 years and over 20 years,
This is a problem that has become apparent.

Accordingly, an object of the present invention is to provide a furnace port structure capable of further extending the life of the furnace port with the recent technological advances in blast furnaces.

[0008]

The present invention solves the above-mentioned problems,
A heat-resistant and wear-resistant liner is installed in places where raw materials cannot be avoided due to prolonged use, and the liner is supported by the cooling panel from below to make it difficult to fall off, and it is extremely easy to replace when the liner is damaged This has been solved by the blast furnace opening structure described above.

That is, according to the present invention, a heat-resistant and abrasion-resistant liner is detachably installed inside a steel shell corresponding to at least a collision portion of a charged material at a mouth portion of a blast furnace. This is a blast furnace opening structure in which a cooling panel having a cooling function is arranged below the gap between the steel shell and the liner.

[0010] In particular, the liner is fixed to the steel shell with a plurality of bolts penetrating the cooling panel, and the cooling panel is a stave, at least at the lower end of which protrudes inward in the furnace radial direction to support the load of the liner. And a cooling box having a cooling tube built into the projecting portion, and a cooling panel which is a stave and projects at least below the steel shell from the steel shell inward in the furnace radial direction to support the load of the liner. Is advantageous for implementation.

Here, in addition to the above-mentioned stave and cooling box, any cooling panel having a cooling water flow passage and having a structure capable of cooling a heat-resistant and abrasion-resistant liner from the back is used. Can be used.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows a furnace opening structure when a stave is used as a cooling panel having a cooling function in the present invention. That is, in the illustrated example, a cast iron stave 6 is provided inside the steel shell 1 around the furnace opening of the blast furnace body.
A heat-resistant and wear-resistant liner 7 is further arranged inside the stave 6, and a nut 8b is attached to a bolt 8a fixed to the liner 7 and extending through the stave 6 to the outside of the steel shell 1. Thereby, the stave 6 and the liner 7 are fixed inside the steel shell 1.

The stave 6 has a rectangular panel shape,
At least on the lower side, that is, the lower side and the upper side in the illustrated example, there are protruding portions 9a and 9b extending inward in the furnace radial direction, and by disposing the liner 7 between these protruding portions 9a and 9b, Is supported by the protrusion 9a. In addition, it is sufficient if the protrusion is located below the liner 7, but as shown in the example in the figure, it is possible to reduce the heat load on the liner 7 from above by installing the protrusion above the furnace. It is more suitable for extending the life.

Further, a cooling pipe 10 for cooling the back surface of the liner 7 and a cooling pipe 11 for cooling the protruding portions 9a and 9b are embedded in the stave 6, and especially a protruding portion forming an end of the stave. By enhancing the cooling of the section and extending the life of the stave 6 body,
Long term maintenance of the furnace mouth structure according to the present invention is realized.

A space between the stave 6 and the steel shell 1 is filled with a castable 12 so that the hot air 13 in the furnace cannot reach the steel shell surface.

Here, the life of the liner 7 is improved by being cooled from the back side by the stave 6, but its wear cannot be avoided in a long-term blast furnace operation. Therefore, in the present invention, the liner 7 can be replaced when the wear of the liner 7 becomes remarkable.
The structure was realized.

That is, the load of the liner 7 is
The liner 7 is easily stabilized by removing the nuts 8b from the bolts 8a when the blast furnace is shut off or the like, since it is supported by the projecting portions 9a below the blast furnace and is directly attached to the furnace shell 1 by the bolts 8a. 6 can be removed. Then, a new liner 7 is introduced into the furnace from a manhole or the like for maintenance of the furnace top charging device, and the bolts 8 a
Into the hole penetrated by the stave 6, and insert the iron
The tip of the bolt 8a projects outside the
The new liner 7 can be easily fixed to the inside of the steel shell 1 by fixing the tip end of the steel shell with the nut 8b from outside the steel shell.

As the liner 7, it is possible to use a cast product containing high Ni and high Cr, which is excellent in abrasion resistance and heat resistance (impact) resistance.

Next, FIG. 3 shows another embodiment of the present invention. In the illustrated example, a plate-shaped stave 6 'is installed at the furnace opening, and cooling boxes 14a and 14b are provided at least below the stave 6', in the illustrated example, below and above, independently of the stave. The tip is provided so as to protrude inward in the furnace radial direction from the front surface of the flat stave.
The cooling box 14a below the stave corresponds to the protrusion 9a below the stave shown in FIG. 2, and supports the load of the liner 7 installed on the front of the stave. On the other hand, the cooling box 14b above the stave corresponds to the protruding portion 9b above the stave shown in FIG. 2, and can reduce the heat load on the liner 7 from above.

The cooling box is a copper box having a labyrinth-like water channel partitioned into walls therein and internally cooled by cooling water flowing through the water channel.

It is preferable that the stave 6 'and the cooling boxes 14a and 14b are restrained from each other by a stopper 15. This is because, during long-term blast furnace operation, various forces are considered to be applied to the steel shell, stave, cooling box, etc. at the furnace mouth, and the load is reduced by restraining the stave and cooling box with a stopper. This is effective in extending the life of the furnace port. Further, in the example of FIG. 3, as in the case of FIG.
It is preferable to prevent the hot gas in the furnace from directly contacting the steel shell 1 by filling the castable 12 between the steel shell 1 and the steel shell 1.

The method of installing the liner 7 is the same as that shown in FIG. 2, and the liner 7 is fixed to the steel shell 1 via bolts 8a. Therefore, if the liner 7 becomes significantly worn after the start of operation of the blast furnace and the liner 7 needs to be replaced, the liner 7 can be easily replaced similarly to the structure of FIG. 2 described above.

[0023]

According to the present invention, the life of the liner is extended by cooling the back of the liner provided inside the furnace at the furnace opening, and the liner which is inevitably worn can be easily replaced. In addition, the original shape of the furnace opening can be always maintained, the controllability of the furnace interior material distribution in the blast furnace operation is stabilized for a long time, and the stable operation of the blast furnace operation is realized.

[Brief description of the drawings]

FIG. 1 is a view showing the structure of a conventional blast furnace furnace opening.

FIG. 2 is a view showing a structure of a blast furnace mouth portion of the present invention.

FIG. 3 is a view showing the structure of another blast furnace opening of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Iron shell 2 Raw material 6 Stave 7 Liner 8a Bolt 8b Nut 9a Projection 9b Projection 10 Cooling pipe 11 Cooling pipe 12 Castable 14 Cooling box

Claims (4)

[Claims] 1. A heat-resistant and abrasion-resistant liner is detachably installed inside a steel shell corresponding to at least a collision portion of a charged material at a mouth portion of a blast furnace, and the liner and the steel shell are connected to each other. A blast furnace opening structure, wherein a cooling panel having a cooling function is arranged below the gap and the liner. 2. The liner is fixed to a steel shell with a plurality of bolts penetrating the cooling panel.
Blast furnace furnace mouth part structure of statement. 3. The cooling panel is a stave, at least at a lower end of which has a protrusion extending inward in the furnace radial direction to support the load of the liner, and a cooling pipe is built in the protrusion. The blast furnace mouth part structure according to claim 1 or 2. 4. The cooling panel according to claim 1, wherein the cooling panel is a stave, and a cooling box projecting from a steel shell inward in a furnace radial direction and supporting a load of the liner is arranged at least below the stave. Blast furnace mouth structure.