JPS62256909A - Method for repairing tapping spout - Google Patents

Abstract

PURPOSE:To make quick and efficient repair work by injecting ultra-high pressure water at the specified amt. of the polishing agent to be incorporated therein, discharge pressure and discharge rate to the eroded part of a refractory wall to break away the eroded part, then packing refractories into said part. CONSTITUTION:The castable refractory wall 12 is attached to the inside of a shell 11 of a tapping spout which is opened on the top surface and has an approximately U shaped section. The ultra-high pressure water incorporated therein with the polishing material is injected from a nozzle 3 to the refractory wall 12 to break away the refractory wall 12 successively from the upper part when the eroded part A is generated in the refractory wall 12. The discharge pressure of the ultra-high pressure water is set at >=1,000kg/cm<2>, the discharge flow rate at <=200l/min, and the amt. of the polishing agent to be incorporated therein at 2-5kg/min. A template 4 is then placed to the inside of the refractory wall 12 and the kneaded castable refractories are packed into the spacing therebetween and are solidified to complete the repair.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention mainly relates to a method for repairing a tap trough that guides hot metal slag tapped from a blast furnace.

(Prior art) Hot metal slag tapped from a blast furnace is separated into hot metal and molten slag in a tap slag. If the castable refractory wall in the tap hole is severely eroded and the corrosion has progressed to a certain extent, another tap hole and tap runner may be used to tap the iron. Repairs are being made to the eroded areas in the iron weighing pit.

(Problems to be Solved by the Invention) The above repair involves a worker entering the taper and destroying and removing the eroded portion of the castable fireproof wall using a rock drill or the like.
Since this is a so-called manual process, it takes a great deal of time and effort to destroy and remove the eroded portion.

On the other hand, the repair work is time-constrained because it is carried out while tapping is being carried out in another tap culvert, and it is relatively difficult to destroy and remove the eroded part once it has completely cooled down. This must be done at high temperatures.

Therefore, the work mentioned above is usually carried out while the tap water is at a high temperature (300° C. or more -1 ton), which poses problems such as forcing the operator to perform very harsh work.

(Level -L for solving the problems) The present invention was invented paying attention to the actual situation as described above. Ultra-high-pressure water with an abrasive of 6 times the size is injected onto the fireproof wall to destroy and remove the eroded parts of the castable fireproof wall, after which a template is placed inside the castable fireproof wall and the castable refractory is filled. Regarding a method of repairing a tap hole by solidifying it and repairing it, the discharge pressure of the ultra-high pressure water is set to 1000 kg/c" or more, and the discharge flow rate is set to 200 i'/c".
The feature is that the abrasive mixture 7A is set at 2 to 5 kg/sin below i+in.

(Function) In general, for castable refractories, the use of water at high temperatures is considered taboo because the refractories become brittle due to rapid cooling, and work that uses large amounts of water concentratedly on localized areas is prohibited. (However, the inventors under certain conditions, i.e. 30
200//ff for castable fireproof walls around 0°C
It was discovered that the use of water at a temperature of less than l1n causes no steam explosion and no problems, and the use of water jets to destroy and remove eroded areas was successfully carried out.

(Example) The repair method of the present invention will now be described in detail based on illustrative drawings.

In the figure, (1) is a tapping trough with a substantially U-shaped cross section, with part 1 open, and a castable fireproof wall (11) inside the steel skin (11).
+2) and a refractory hearth bottom (13) is installed at the bottom of this refractory wall (12). Further, this tap trough (1) is used by being connected to a tap hole (2) of a blast furnace (not shown). In addition, in the figure (14)
(15) is a skimmer damper, (IG) is a residual iron plate 1-
It is 21.

Further, (3) is an ultra-high pressure water nozzle used in the method of the present invention, which includes an ultra-high pressure water supply passage (31) and an abrasive supply passage (32), and is supplied from this passage (32). The polished abrasive material is placed in ultra-high pressure water in a four-piece mixing chamber (33), and is sprayed together with the ultra-high pressure water from an injection port (34). Note that this abrasive has a particle size of No. 4 (0,
4-0.8. , ) grade silica sand or diamond sand is used.

When erosion spots (A) as shown by broken lines occur on the castable fireproof wall (12), ultra-high pressure water mixed with an abrasive is injected to the fireproof wall (12). At this time, the discharge pressure of ultra-high pressure water was set to 1 OOOkg/cm" or more, the discharge flow rate was set to 20Of/1n or less, and the amount of abrasive mixed was set to 2
~5 kg/win, and as a result, the castable fireproof walls (12) are sequentially destroyed and removed from above. In detail, as shown in Fig. 4 (the nozzle (3) is slightly inclined with respect to the vertical line by straightening the castable fireproof wall (12), and the nozzle (3) is injected 1 (3)
4) is positioned a predetermined distance outward (thick side) from the innermost surface of the castable fireproof wall (12), first, the inner upper corner of the castable fireproof wall (12) is obliquely destroyed and removed;
Next, as shown in Figure 5.6, move the nozzle (3) outward while tilting it, and install the castable fireproof wall (12).
1111 Removal Destruction is carried out by sequentially scraping off the sloped surface to completely destroy and remove the eroded part (A) of the castable fireproof wall (I2) as shown in Fig. 7, or
As shown in the figure (nozzle (:l) wo+ + s9 fuJ'
vfiJ firewall (12>(1) invasionffJiF'As(k)
A concave groove (17) is formed at the C position of this eroded portion (A) slightly toward the C position, and then a concave groove (I7) is formed as shown in FIG.
) in the same manner as before, and then direct the nozzle (3) from above toward the castable fireproof wall (12) as shown in Figure 1O. Destroy and remove one part from the groove (I8) of the fireproof wall (12),
Subsequently, the upper portion of the groove (I7) is similarly destroyed and removed to completely destroy and remove the eroded portion (A). In addition, in this work step, it is sufficient to mount an articulated arm unit on the east side of the Mekushiri Daito, attach the nozzle (3) to the tip of the arm unit, and perform each of the operations described below.

Thereafter, as shown in FIG. 7, with the template (4) placed inside the castable refractory wall (12), the kneaded castable refractory is filled into the gap and solidified.

In the above example, the discharge pressure of ultra-high pressure water was set to 2000k.
g/c+", the discharge flow rate was set to 201/m+n, and 3 kg/min of 4-La silica sand was mixed into this ultra-high pressure water to destroy and remove the castable fireproof wall (12). The destruction/removal capacity was 60 m/min.

(Effects of the Invention) As explained in 1-1, the tap hole repair method according to the present invention is as follows:
A water jet mixed with abrasives is used to destroy and remove the eroded parts of the castable fireproof wall in the tap runner, allowing repair work to be carried out in an extremely short time and efficiently, and without requiring workers to enter the tap machine. This eliminates the need for additional work, reducing the burden of labor on the part of the operator.

[Brief explanation of drawings]

The drawings show an embodiment of the method of the present invention; FIG. 1 is a longitudinal sectional side view of a tap runner, FIG. 2 is a longitudinal sectional front view thereof, and FIG. 3 is a longitudinal sectional view of a nozzle used in the method of the invention. 4 to 7 are vertical sectional front views showing the working steps of the method of the present invention, and FIGS. 8 to 11 are vertical sectional front views showing another process f. (+)...Tapping runner, (12)...Castable fireproof wall, (2)...Tapping hole, (3)...Ultra-high pressure water nozzle, (4)...Template , (A)... Invasion Ji Department. Figure 1 Figure 3 Figure 2

Claims (1)

[Claims] A tapping trough with an open upper surface and approximately U-shaped cross section injects ultra-high pressure water mixed with an abrasive material against the castable fireproof wall inside to destroy and remove the eroded parts of the castable fireproof wall, and then castable. A method of repairing by applying a template to the inside of the fireproof wall and filling and solidifying castable refractories, the discharge pressure of the ultra-high pressure water is 1000 kg/cm^2 or more, the discharge flow rate is 200 l/min or less, and abrasives are mixed. amount 2-5
A method for repairing a tap trough, characterized by setting the rate at kg/min.