JPH10130708A - Closing method of blast furnace taphole - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable stable tapping by eliminating horizontal holes generated in a blast furnace tapping hole. SOLUTION: When a mud material is press-fitted into a blast furnace taphole, filled and clogged, filling is performed at a high speed during a taphole depth of 0 to 2 m,
Filling is performed at a low speed during a depth of 2 to 3 m, and is performed at a high speed when the depth is 3 m or more. Thereafter, a hole is formed with a metal rod or a drill to a depth of 2 to 3 m, and the hole is filled with a mud material having high corrosion resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for closing a tap hole of a blast furnace, and more particularly to closing a tap hole with a mud material so as to eliminate a lateral hole generated at a depth of 2 to 3 m. About the method.

[0002]

2. Description of the Related Art Generally, in the operation of a blast furnace, a tap hole is opened at the time of tapping so that molten metal flows out, and after tapping, a mud material is injected into the tap hole by a mud gun to close the tap hole. However, in actual tapping, as shown in FIG.
At the tap hole 2 provided in the blast furnace wall 1 at a depth of 2 to 3 m, a horizontal hole 3 generated by erosion of pig slag at joints or cracks of bricks is generated, and the tapping is not necessarily smooth. In many cases, this is not performed, and there is a high danger that the tapping speed will be extremely reduced, the remaining piggyback will be embraced, and operational problems will be caused. Further, since the hot metal is discharged out of the furnace through the horizontal hole 3, the horizontal hole 3 must be eliminated from the viewpoint of protection of the furnace bottom such as erosion of the brick near the taphole.

As shown in FIG. 5, a blast furnace tap hole is closed by attaching a mud gun 4 to a tap hole 2 provided on a blast furnace wall 1 and discharging the mud material 5 at a substantially constant press-in speed. Generally, the injection is performed by a method of injecting into the pouring hole 2. However, in the method of injecting the mud material at a substantially constant speed when the blast furnace tapping hole is closed, the lateral hole 3 can be effectively eliminated. Did not.

[0004] For example, Japanese Patent Application Laid-Open No. 56-84407 proposes a method of filling a mud material at a high speed in an early stage of clogging and at a low speed in a later period. Since the position of occurrence is usually not constant,
When high-speed filling is performed at the position where the lateral hole exists, there is a problem that the lateral hole is not filled with the mud material and the lateral hole cannot be closed.

Japanese Patent Laid-Open Publication No. Hei 6-330118 proposes a method of closing a tap hole by controlling a filling rate of a mud material in accordance with a mud pressure and a filling stroke. Even if the mud material has low porosity and high durability, a method of reliably filling the lateral hole 3 with the mud material and closing the same as in the method described in the above-mentioned JP-A-56-84407. That is not enough.

[0006] Further, Japanese Patent Application Laid-Open No. 1-127612 proposes a method of closing a tap hole by filling a mud material in two steps. Although effective in preventing the expansion, it is not effective as a method for effectively filling the mud material into the lateral hole 3 where the generation position is not constant.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the problems in the conventional tap hole closing method described above, and prevents smooth tapping and prevents the tapping speed from extremely lowering. An object of the present invention is to propose a method of closing a blast furnace tap hole, which can effectively eliminate a side hole that has a high risk of inviting and remaining iron and causing operational trouble.

[0008]

According to the present invention, there is provided a method for press-fitting and filling a mud material into a tap hole of a blast furnace, and closing the tap hole. When closing the mouth, high-speed filling between depth 0 and 2m, depth 2
Filling the mud material by changing the filling speed according to the taphole depth, and filling the mud material at a low speed between 3 m and 3 m or more, and then filling it with a metal rod or drill up to the horizontal hole occurrence site at a depth of 2 to 3 m. The gist of the present invention is a method of forming a hole by a method and filling the hole with a mud material having high corrosion resistance.

[0009] The taphole depth is usually between 3 and 4 m,
Most of the lateral holes are generated at a depth of 2 to 3 m, which causes various troubles as described above. Therefore, the filling of the mud material is usually performed at once at a high speed filling, but when a horizontal hole is generated, the filling speed is changed to a high speed filling at a tapping hole depth of 0 to 2 m, and at a depth of 2 to 3 m. Is a low-speed filling, and a high-speed filling is performed at a depth of 3 m or more. That is, in the present invention, as means for securely closing the lateral hole,
The method of reducing the filling speed of the mud material during the tap hole depth of 2 to 3 m where many side holes are generated was used. The reason is that the filling speed of the mud material is too fast in the conventional high-speed filling, and the filling of the mud material in the side hole portion is not always performed sufficiently.By filling at a low speed, the filling in the side hole portion can be sufficiently performed. Because it becomes. The filling speed of the mud material is determined in consideration of the ability of the mud gun to be used, the viscosity of the mud material, the type and amount of the binder, and the like. To give a specific example, a high speed of 3.2 to 3.5 cm / sec and a depth of 2 to 3 m during the tap hole depth of 0 to 2 m
During this period, the speed is low at 2.5 to 2.8 cm / sec, and when the depth is 3 m or more, the speed is high at 3.2 to 3.5 cm / sec.

As described above, when the filling rate of the mud material is changed in accordance with the depth of the taphole, the filling is performed at a depth of 2 to 3 m.
A hole is formed with a metal rod or a drill up to the location where the lateral hole occurs, and the hole is filled with a high corrosion resistant mud material. The reason for taking such a method is that the lateral hole is completely filled by the first filling of the mud material. This is due to consideration of the case where it is not blocked. That is, if a hole is formed up to the horizontal hole occurrence portion at a depth of 2 to 3 m immediately after the first filling of the mud material, the quality of the filling of the mud material with respect to the lateral hole can be checked. There is no particular problem when the hole is completely closed, but when the side hole is not completely closed, the side hole can be reliably closed by filling the portion with a high corrosion resistant mud material. . Of course, even if the horizontal hole is completely closed by the first filling of the mud material, the horizontal hole can be more completely closed by filling the mud material having high corrosion resistance. The depth of a hole formed by a metal rod or a drill, that is, the location of occurrence of a lateral hole can be easily and accurately confirmed by marking the holder of the metal rod or the drill. The mud material used for filling the holes is made of a material having high corrosion resistance, in order to further enhance the effect of preventing the lateral holes and to effectively protect the brickwork around the holes.

[0011]

FIG. 1 is a schematic longitudinal sectional view of a blast furnace taphole at the time of filling a mud material according to an embodiment of the present invention, and FIG. 2 is a lateral view at a depth of 2 to 3 m immediately after the first filling of the mud material. FIG. 3 is a schematic side view showing an example of a hole forming apparatus using a metal bar shown in FIG. 2, in which a hole is formed with a metal bar up to a hole generation site, FIG. Hole.

That is, the present invention changes the filling speed of the mud material 5 by the mud gun 4 when closing the taphole 2 in which the lateral hole 3 is generated at a depth of 2 to 3 m.
High-speed filling (3.3 m / sec) during 2 m, depth 2-3
During m, low-speed filling (2.6 cm / sec) and at a depth of 3 m or more, high-speed filling (3.3 cm / sec). That is,
Since the mud material is filled at a low speed during a depth of 2 to 3 m where many lateral holes 3 are generated, the mud material 5 which is filled at a low speed is sufficiently filled into the portion of the lateral hole 3 as shown in FIG. The pig hole 2 and the horizontal hole 3 are completely filled with the mud material 5 and completely closed.

Further, in the present invention, when the first filling of the mud material is completed, the hole forming device 6 forms the hole 7 with the metal rod 6-3 to the position where the horizontal hole 3 having a depth of 2 to 3 m is generated. As shown in FIG. 3, the hole forming apparatus 6 includes a long drifter holder 6-1 provided with a scale 6-4, and a drifter 6-2 for forming a hole is mounted to be movable back and forth.
A hole of a predetermined depth is formed in the tap hole 2 with a metal rod 6-3 connected to the metal rod 6-2. Is to be held through. It should be noted that the moving distance of the drifter 6-2, that is, the depth of the hole can be confirmed by using a method of electrically detecting instead of the scale.

When the hole 7 is formed by the metal bar 6-3 to the position where the lateral hole 3 having a depth of 2 to 3 m is generated by the hole forming device 6, the filling state of the mud material initially filled using this hole is confirmed. Then, the hole is filled with a mud material having high corrosion resistance. Thereby, the horizontal hole 3 is completely eliminated, and the generation of the horizontal hole when the tap hole is opened can be reliably prevented. Incidentally, the results of applying the method of the present invention to an actual furnace show that the tapping time (181 minutes / tap), the filling amount of the mud material (500 kg / pt), and the taphole depth are lower than those of the conventional closing method using only high-speed filling. (3.2-
3.3 m), there was no great difference, but the lateral hole generation rate was about 3.0% in the prior art, while the present invention was able to achieve almost 0%.

[0015]

As described above, according to the method of the present invention, the mud material filling speed is changed to a high speed, a low speed, and a high speed to fill the mud material, so that the mud material is reliably filled in the lateral hole portion. By filling the side holes with a highly corrosion-resistant mud material, the side holes can be more completely closed, so that the generation of side holes when tap holes are opened can be reliably prevented and stable. It has an excellent effect of securing a stable tapping and greatly contributing to the stable operation of the blast furnace.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of a blast furnace taphole at the time of filling a mud material according to an embodiment of the present invention.

FIG. 2 is a schematic longitudinal sectional view showing a state in which a hole is formed with a metal rod up to a horizontal hole occurrence site having a depth of 2 to 3 m immediately after the first filling of the mud material.

FIG. 3 is a schematic side view showing an example of a hole forming apparatus using the metal rod shown in FIG.

FIG. 4 is a schematic longitudinal sectional view showing a situation where a horizontal hole is generated in a blast furnace taphole.

FIG. 5 is a schematic longitudinal sectional view showing an example of a conventional method of closing a blast furnace taphole.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blast furnace wall 2 Tap hole 3 Side hole 4 Mud gun 5 Mud material 6 Hole forming device 6-1 Drifter holder 6-2 Drifter 6-3 Gold rod 6-4 Scale 6-5 Fixture 7 Hole 8 Bracket

Claims (1)

[Claims] 1. A method of closing a tap hole by inserting a mud material into a tap hole of a blast furnace and filling the tap hole with a hole at a depth of 2 to 3 m. ~ 2
m, filling at high speed, filling at low speed between 2 and 3m, filling at high speed at depth of 3m or more, filling the mud material by changing the filling speed according to taphole depth, and then 2-3m depth A method for closing a blast furnace tap hole, characterized in that a hole is formed with a metal rod or a drill up to the horizontal hole occurrence site, and the hole is filled with a highly corrosion-resistant mud material.