JPS5967307A - Operating method of converter - Google Patents

Abstract

PURPOSE:To enable the restarting of operation with a short downtime by removing only the base part of the bottom blowing tuyere of a converter that has attained the time for replacement, packing a solid or castable blind material in the space made after the removal to close the same and continuing the operation. CONSTITUTION:The tuyere retaining brick 4 of a bottom tuyere 1 of a converter that has attained the time for replacement is removed, and only the base part on the furnace outside is removed except the inside part 1' of the tuyere 1 to make a space 6 after removal remaining a part of a sleeve 2. A solid blind material 7 formed by molding beforehand refractories such as dolomite, MgO-C base or the like to a prescribed shape is tightly fitted and packed in the lower part of the sleeve 2 in the space 6, whereafter castable refractory is sprayed in the spacing between the brick 3 and the material 7 to form a castable blind material 8, whereby a retaining function is provided to the material 7 and the spacing between the material 7 and the brick 3 is tightly joined to each other and is sealed.

Description

[Detailed description of the invention] The present invention relates to a top-bottom blowing converter operating method.

As is well known, in order to strengthen the agitation of the steel bath and reduce the amount of dust in the generated gas, oxygen is blown into the steel bath through a top blowing lance, and stirring gas is injected through the bottom blowing tuyere below the surface of the steel bath. Top-bottom blowing converter operation, which performs blow refining, has been actively adopted in recent years. The stirring gas is generally carbon dioxide, an inert gas, a mixture thereof, or a mixture of these gases with a small amount of oxygen added, and the amount of gas blown into the gas is determined depending on the steel type and the type of steel so as to efficiently achieve the above purpose. It is appropriately set and controlled by other refining conditions. By the way, the bottom blowing tuyeres for blowing the stirring gas into the furnace are installed by providing holes in the iron shell and lining brick wall of the bottom of each converter.
The bottom blowing tuyere and the brick wall near its attachment point are subject to slight erosion and wear due to direct contact with the stirring flow of molten steel generated by gas injection, and the high temperature of the molten steel and the cooling of the stirring gas. This causes spalling, which shortens its lifespan compared to the brick walls of other parts of the furnace.

Conventionally, bottom-blown tuyeres that have reached the time for replacement have been forced to be replaced in hot conditions due to productivity issues, etc.
Replacement work in such hot conditions requires a long time under adverse working conditions, and it is difficult to tightly attach and fix the replaced bottom blowing tuyere to the lining brick wall. It is difficult and has the problem of causing hot water to leak.

As a countermeasure, several spare bottom blowing tuyeres are installed on the hearth bottom in advance, and when the tuyeres reach the time to be replaced,
A method has been proposed in which the tuyere is blinded and the operation is continued by switching to the spare tuyere. Therefore, in the method,
Conventionally, bottom blow tuyeres that have melted and are due for replacement (hereinafter, bottom blow tuyeres that have reached the replacement time are referred to as replacement tuyere, and bottom blow tuyeres are simply referred to as ``wings''). In order to save money, the entire replacement tuyere was removed and then filled with a refractory nozzle molded into a predetermined shape. However, since the brick walls in and around the tuyeres have suffered severe erosion as mentioned above, only the replacement tuyere was replaced with the brick walls. Upon leaving, the tuyeguchi sofu ha+(
11jl 'I's U4j tile wall is often touched by Jt↓1, and the supplementary 1φ of the row is 5 necessary, and the fact that there is a 2nd set is b
It is similar to the case of replacing the tuyere, so it takes a little more time to replace the tuyere than it does to replace the tuyere.
Although the process was short, it still took a long time, and therefore the converter operation was interrupted for a long time, and there was an associated loss of thermal energy.

The purpose of the present invention is to provide a converter operating method including a method for solving the problems of the present invention and making the bottom-blowing converter operation efficient. This is a converter operating method characterized by removing only the base of the converter bottom blowing tuyere that has reached the required period, filling and closing the removal space with regular and/or irregularly shaped particles, and continuing the operation.

Hereinafter, the method of the present invention will be explained in detail based on Examples.

Fig. 1 is a cross-sectional view showing a general siding installation part and the hearth bottom structure in its vicinity, where ■ is the siding, 2 is the sleeve brick, and 3 is the siding.
1 is a hearth brick, and 4 is a tuyere brick.

5 is a stirring gas supply pipe to the tuyere 1.

The tuyere 1 will have a shape as illustrated by the broken line and immediately implement the unification.

Fig. 2 shows an example based on the present invention, and when converting the 5 tuyeres into 1, the 5 tuyere j1P and the brick 4 are removed, and only the base on the outside of the furnace is removed, leaving the furnace interior 111J portion 1' of the tuyere 1. Then, a part of the sleeve 2 is exposed to form a removal space 6. For example, as shown in Figure 1M1, a gas blowing header 11 is buried in the bottom of the tuyere l, and a thin tube 12
For those with a structure in which stirring gas is blown into the furnace through a
'Removal space 6. Next, in the removal space 6, a third
As shown in the figure, a regular shaped material 7 made of dolomite or MgO-0 type refractory material, which is previously formed into a predetermined shape, is filled.

Obstruction. Also, in this example, after the fixed shaped blind shrine 7 marked with hf'f'J is tightly fitted into the lower part of the sleeve 2, a missing refractory is blown into the gap between the hearth brick 3 and the fixed shaped N shrine 7. A laminated block 8 (irregular shaped 1 shrine) 8 is formed, which has a function of holding down the fixed shaped 1 material 7, and also closely fits and seals the gap between the fixed shaped 1 material 7 and the hearth brick 3. , making complete occlusion possible.

FIG. 4 shows another example of the present invention, in which the entire removal space 6 including the lower part of the sleeve is filled with an irregularly shaped material 70, and the tuyere is
It's a blockage. In this example, it is necessary to dry the filling material i, but the lower end iAi 1 of the tuyere l whose base has been removed
This is effective when applied when a is not a smooth surface.

Once the replacement tuyere 1 has been completed, the supply of stirring gas can be switched to the spare tuyere 10 as shown in FIG. 5, and the operation can be started immediately. )
For example, when the panel is not in operation, that is, when gas is not being blown, the blind sleeve 9 is attached to the mounting hole, and when switching from the standby state to the operating panel, the blind sleeve 9 is removed to restore the normal panel. All you have to do is replace it with 10.

Since the blind sleeve 9 does not undergo severe erosion like the tuyeres during operation, the blind sleeves can be replaced easily and in a short time.
Therefore, it can contribute to shortening the switching work.

According to the method of the present invention, only the base of the replacement tuyere 1 is removed,
Since the removal space 6 including the lower part of the sleeve is filled and closed with regular and/or irregular shaped materials, it will break, so when the core size of the siding progresses and it is time to replace it, the outside of the converter that is not melted or damaged will be removed. Since the base of the siding is removed, the removal work is faster and safer than removing the entire siding, and the shape of the siding can be reliably maintained without damaging the sleeve or the furnace brick wall. can be removed. Therefore, operation can be resumed after a short interruption, which has the effect of improving productivity and greatly reducing loss of thermal energy.

It took more than 4 hours to enrich the entire surface, but in the example shown in FIG. 3 based on the present invention, the enrichment could be achieved in about 1 hour, and the tW during the work could be greatly shortened. . As described above, the method of the present invention has extremely great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a general siding and the hearth structure in its vicinity, Figs.
Figure 2 shows the situation after removal of the base of the wing, and Figure 3 is a sectional view showing the situation after filling and closing with regular shaped I material. FIG. 5 is a cross-sectional view showing the condition of a filled open substrate with an irregularly shaped blind hole, and FIG. ■, 10 tuyeres, 2 sleeve bricks, 3: hearth smoked tiles, 4
: Padding brick, 5: Stirring ('V gas supply pipe. 6: Removal space, 7: Shape ladle, 70: Amorphous d-lin 8: Light side L 9: 1 sleeve, Agent: Masamoto Akisawa, patent attorney) 2 people outside

Claims (1)

[Claims] (1) A converter characterized by removing only the base of the converter bottom blowing tuyere that has reached the time of replacement, and filling and closing the removal space with regular and/or irregularly shaped flax to continue operation (;■ Business law.