JPS6011084Y2 - Blast furnace mouth structure - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a furnace body structure of a shaft portion located directly below the furnace mouth of a blast furnace.

At the mouth of a blast furnace, in order to protect the furnace body from impact and abrasion of the burden and to maintain proper distribution of the burden, an ore support is generally placed inside the shell 1, as shown in Figure 1. 2 will be installed.

The lower part of the ore receiver 2 is called a shaft part and is made of brickwork.

Approximately 80% of the area from the bottom of the shaft is 800% inside the furnace.
Because the temperature exceeds 'C, a cooling plate or staple is embedded in the furnace body for forced cooling, but the average temperature of the upper part of the shaft (approximately 20% from the upper end of the shaft) is 600°C. ℃, so forced cooling is not performed, and normally, as shown in the figure, the structure is such that iron bricks 12 are partially stacked on refractory bricks 5 in order to prevent the bricks from wearing out or falling off. There is.

However, the upper part of the shaft maintains a relatively low temperature of around 600℃ on average, but in reality it ranges from 400℃ to 90℃.
Because the bricks undergo repeated temperature changes up to 00°C and are subjected to intense repeated thermal stress, they begin to fall off within four to five years after being fired.

When the bricks at the top of the shaft fall off, unevenness occurs on the inner wall surface of the furnace in this area, which not only causes uneven unloading of the charge, but also causes the steel shell to overheat and cause damage to the steel shell.

Furthermore, if the bricks fall off severely, the ore support loses its support and falls off, making it impossible to operate the blast furnace.

The present invention has been developed in view of the above.Instead of the bricks, a metal cooling body with a refrigerant flow board is attached to the upper part of the shaft where the bricks tend to fall off, thereby preventing wear and tear on the part. This was designed to stabilize the unloading of steel, protect the steel shell, and ensure stable operation of the blast furnace.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

In FIG. 2, numeral 1 is an iron shell that is placed on the exterior of the blast furnace, and numeral 2 is an ore support installed at the mouth of the blast furnace.

A bracket 3 is provided between the furnace mouth part and the shaft part below it, and supports the ore support 2.

A plurality of metal cooling bodies 4 are disposed in the circumferential direction on the upper part of the shaft portion with their surfaces exposed to the inside of the furnace (see FIG. 3).

In this case, it goes without saying that the cooling body 4 is provided with an angle and curvature commensurate with the inclination and diameter of the furnace inner wall surface.

Each cooling body 4 rests on refractory bricks 5 lining the skin 1 below, and a plurality of horizontal carrier arms 6 fixed to the back side of the cooling body 4 line the skin 1. penetrate through,
A nut 8 is screwed into a thread 7 carved at the tip of the carrier arm 6 from outside the furnace, and is removably fixed to the steel shell 1.

In order to improve the stability of the cooling body 4, the bottom of the cooling body 4 is bent backward.

Each cooling body 4 also has a refrigerant pipe 9 inside thereof, and is provided so as to be forcibly cooled from the inside by passing a refrigerant such as water therethrough.

Such a cooling body can be easily manufactured by, for example, casting a steel pipe bent into a predetermined shape with cast iron.

An example of refrigerant piping for the cooling body 4 is shown in FIG.

There is a gap between the cooling body 4 and the iron skin 1 behind it, into which a monolithic refractory 10 such as mortar or castable is filled.

11 is a cap that seals between the iron skin 1 and the carrying arm 6;
It is detachably attached to the steel shell 1 so as not to obstruct the attachment and detachment of the cooling body 4.

By constructing the upper part of the shaft portion of the blast furnace as described above, the following effects are produced.

■ Remove the brick from the upper part of the shaft and replace it with cooling body 4.
, the bricks are completely prevented from falling off, and since the cooling body 4 is fixed to the steel shell 1, there is no fear of it falling off.

■ Since the cooling body 4 is forcibly cooled by passing a refrigerant such as cooling water inside, it is less susceptible to changes in the temperature inside the furnace, and changes in thermal stress are reduced, resulting in a lifespan of 14 generations, that is, 7
Extends to ~8 years.

(2) Also, since the surface of the cooling body 4 is directly exposed to the inside of the furnace, the inner wall surface of the furnace is maintained in the desired shape during its service life.

■ As a result of forcibly cooling the cooling body 4, the life of the monolithic refractory 10 between the cooling body 4 and the shell 1 is extended, and the cooling body 4 and the monolithic refractory 10 to ensure protection.

Furthermore, even in the unlikely event that the monolithic refractory 10 is damaged, since the monolithic refractory 10 is supported from the inside of the furnace by the cooling body 4, it can be easily repaired from the side of the steel shell 1. .

Therefore, according to the present invention, the life of the upper part of the shaft part, which was conventionally said to be 4 to 5 years after firing, can be extended to 14 years at a stretch, and during this period, good unloading can be guaranteed, and the ore receiver can be It also prevents falling off, which has a great effect on stable operation of the blast furnace.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing the conventional structure of the blast furnace mouth and the upper part of the shaft directly below it, Fig. 2 is a longitudinal cross-sectional view illustrating the structure of the same part according to the present invention, and Fig. 3 FIG. 2 is a front view illustrating the structure of the cooling body according to the invention. Brief explanation of the drawings, 1: Iron shell, 2: Ore support, 4: Cooling body, 5: Refractory brick, 6: Carrying arm, 9: Refrigerant piping, 1
0: Monolithic refractory, 12: Iron brick.

Claims (1)

[Scope of utility model registration request] A cooling body with a coolant flow path is placed directly under the ore receiver at the mouth of the blast furnace.
1. A blast furnace mouth structure, characterized in that a monolithic refractory is loaded between the cooling body and the iron shell, supported by carrier arms fixed to the iron shell.