JP2001342507A - Disassembling method for blast furnace staves - Google Patents

Abstract

PROBLEM TO BE SOLVED: To disassemble the staves just to be exchanged regardless of the wear of the inner face side of a blast furnace without damaging adjacent staves or a shell. SOLUTION: When a stave 1b is pushed out to the inside of blast furnace to change it, a cooling piping 1bd which is positioned at the shell opening of the stave 1b to be changed is cut, and the portion 1ba of the stave 1b interfering in the adjacent stave is cut off. Then, the interfering portion 1ba and the stave 1b separate therefrom are pushed out to the inside of the furnace without damaging the adjacent stave and the shell.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing a stave containing a cooling water passage for cooling a blast furnace body from the blast furnace body.

[0002]

2. Description of the Related Art Conventionally, a stave 1 is fixed to a steel shell 3a of a blast furnace 3 using bolts and nuts 2 as shown in FIG. As shown in FIG. 4, the staves 1 are divided radially from the center in the cross-sectional direction of the blast furnace 3, and the gaps 4 between the adjacent staves 1 are filled with refractories. I have.

If the refractory filled in the gap 4 falls off or disappears, hot air in the blast furnace enters the space and the steel shell 3a becomes red-hot. The gap 4 is required to be as small as possible. Therefore, as shown in FIG. 4, the cross-sectional shape of the stave 1 alone is smaller than the furnace inner chord size La than the furnace inner chord size La.
Are formed to have a fan shape in a plan view corresponding to the circular arc of the iron shell 3a in the cross section.

On the other hand, an ideal blast furnace is obtained by changing the thickness of the stave greatly in the height direction between the inner surface of the blast furnace (blast furnace profile) in the longitudinal sectional direction and the steel shell shape. The inner surface of the furnace and the shell shape are formed.

[0005]

However, the conventional stave having the above-mentioned shape has the following disadvantages.

As shown in FIG. 5A, in a stave 1 a having a vertical cross-sectional shape in which the thickness does not change greatly in the height direction, after 5 to 6 years have passed since the blast furnace was turned on, the heat in the furnace and the contents of the blast furnace As the wear on the inner side of the furnace of the stave 1a progresses due to the contact with the object and the thickness of the stave decreases, the stave thickness decreases.
As shown in (b), there is no interference with the adjacent left and right staves 1a, and extrusion into the furnace is possible.

However, in the case where an equipment defect is found in the attached stave 1a immediately after the completion of the installation of the stave 1a, the furnace inner surface side of the stave 1a is placed in the furnace shown in FIG.
As shown in (a), since it is not worn, stave 1
When the stave 1a is to be replaced, the stave 1a is extruded into the furnace as shown in FIG. 6B because the cross-sectional shape of the stave 1a is larger than the inner chord size La of the furnace. Is impossible because of interference with the adjacent left and right staves 1a.

On the other hand, as shown in FIG. 7A, in a stave 1b having a vertical cross-sectional shape whose thickness changes greatly in the height direction, the furnace of the stave 1b is provided in a cross-sectional portion of the thick portion 1bb. Even when the thickness of the stave 1b is reduced due to the progress of the inner surface wear, the interference between the adjacent left and right staves 1b exists, so that the conventional height shown in FIGS. As in the case of the stave 1a whose thickness does not greatly change in the direction, it is impossible to remove it by pushing it into the furnace.

Therefore, as shown in FIG. 7 (a), in the stave 1b having a vertical cross-sectional shape whose thickness changes greatly in the height direction, it is impossible to replace the stave 1b during the blast furnace operation when the wind is shut off. In the case of such a stave 1b, replacement has not been conventionally performed. However, if the operation is continued without replacing the stave 1b and the wear further progresses, an accident occurs in which the cooling water flow path 1bc of the stave 1b is damaged, and the circulation of the subsequent cooling water stops, and the stave cooling becomes impossible. This may lead to abnormal wear or chipping of the stave body near the damaged cooling water flow path, or may cause abnormal heating of the blast furnace body steel shell or cracks in the steel shell. Situation.

[0010] In JP-A-57-126905,
A method of removing a stave by exploding an explosive loaded from the steel side has been disclosed, but a safe and reliable method from the viewpoint of preventing the propagation and damage of impact force to an adjacent stave and the steel is disclosed. I can't say.

SUMMARY OF THE INVENTION The present invention has been made to solve the problem at the time of stave removal caused by the shape of the stave as described above. It is an object of the present invention to provide a method for removing only a stave to be replaced regardless of wear.

[0012]

In order to achieve the above object, a method for removing a blast furnace stave according to the present invention comprises cutting a cooling pipe located at an opening of a steel shell of a stave to be replaced, and then removing the steel pipe. A portion of the stave to be replaced that interferes with an adjacent stave is cut off from the opening, and then the stave is extruded into a furnace. By doing so, it is possible to extrude only the stave to be replaced into the furnace irrespective of the wear on the furnace inner surface side without damaging the adjacent stave or steel shell.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a method for removing a blast furnace stave according to the present invention, a cooling pipe located at an opening of a steel bar of a stave to be replaced is cut when extruding the stave into a furnace for replacing the stave. Thereafter, a portion of the stave to be replaced, which interferes with an adjacent stave, is cut off from the opening of the steel bar, and then the stave is extruded into a furnace.

In the method for removing a blast furnace stave according to the present invention, the term “separation” means, in addition to mechanical cutting,
This is a concept that includes fusing like gas cutting.

In the method for removing a blast furnace stave according to the present invention, after cutting a cooling pipe located at a steel opening of a stave to be replaced, the steel pipe opening interferes with an adjacent stave of a stave to be replaced. Since the part is cut off, there is no damage to adjacent staves or steel. Then, after the part that interferes with the adjacent stave is cut off, the stave to be replaced can be extruded into the furnace and removed regardless of wear on the furnace inner surface side.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for removing a blast furnace stave according to the present invention will be described below with reference to the embodiments shown in FIGS. 1A and 1B are explanatory views of a method for removing a blast furnace stave according to the present invention, wherein FIG. 1A is a view as viewed from a longitudinal sectional direction of a stave to be removed, and FIG. FIG. 2C is a schematic perspective view of a stave to be removed, and FIG.
(B) is the figure seen from the longitudinal section of other staves applied to the method of removing the blast furnace stave according to the present invention.

FIG. 1 shows a stave 1 having a longitudinal cross-sectional shape in which the upper end protrudes toward the steel skin side and the thickness in the height direction greatly changes.
b is an explanatory view of removing the worn stave 1b in order to replace the stave with a new stave when the furnace inner surface is worn out. The steel-side portion interferes with the adjacent stave 1b and cannot be removed.

Therefore, in the present invention, when extruding the stave 1b into the furnace in order to replace the stave 1b whose inner surface of the furnace has been worn, the stave 1b to be replaced is to be replaced.
1bd (FIG. 1)
(B), after cutting the cooling pipe on the left side of the paper of the central stave 1b), a portion of the stave 1b to be replaced, which interferes with the adjacent stave 1b, that is, the interference portion For example, 1ba is gradually cut from the steel shell side.

At this time, the stave 1b to be replaced
The shape and the cutting width of the interference portion 1ba are determined so that the furnace outer chord size Lb ′ of the stave 1b main body after removing the interference portion 1ba of the stave 1b is smaller than the furnace inner chord size La ′.

After the interference part 1ba is cut, the stave 1b separated from the interference part 1ba does not interfere with the adjacent stave 1b when extruded into the furnace, and can be extruded into the furnace. become. After extruding the separated stave 1b, the cut interference part 1ba is also extruded into the furnace.

In the above embodiment, the interference portion 1ba of the stave 1b to be removed is cut into a wedge shape, and the interference portion 1b is first cut.
extrude the stave 1b separated from a into the furnace,
The example in which the wedge-shaped small piece as the interference part 1ba is extruded into the furnace has been described. However, when the interference part is very small and the separated interference part can be extruded into the furnace first, After extruding the interference part after separation into the furnace first, the stave separated from the interference part may be extruded into the furnace, and the interference part is very small, and after the gas cut, the interference part is placed in the furnace. If not, only the relevant stave after gas cutting need only be extruded into the furnace.

The stave to which the method of the present invention is applied is shown in FIG.
Is not limited to the shape in which the upper end protrudes toward the steel skin side as shown in FIG. 2A, the U-shaped as shown in FIG. 2A, or the upper end as shown in FIG. May project to the inside of the furnace, or may be omitted, but may have a lower end projecting to the inside of the furnace or a center projecting to the inside of the furnace, contrary to FIG. 2B.

Further, the method of the present invention is not limited to the stave in which at least the upper end, the lower end, or the center protrudes inside the furnace as described above, and the thickness in the height direction as shown in FIGS. A stave 1 having a longitudinal sectional shape that does not change significantly
Immediately after the installation of a is completed, the present invention can also be applied to the removal in a case where an equipment defect is found in the installed stave 1a.

[0024]

As described above, according to the method for removing a blast furnace stave according to the present invention, after cutting a cooling pipe located at an opening of a steel bar of a stave to be replaced, the stove is replaced from the opening of the steel bar. Since the portion of the stave to be interfered with is separated from the adjacent stave, the adjacent stave and the steel are not damaged. Then, after the part that interferes with the adjacent stave is cut off, only the stave to be replaced can be pushed out into the furnace and removed regardless of the wear on the furnace inner surface side.

That is, according to the method for removing a blast furnace stave according to the present invention, a stave that has been impossible to extrude into a furnace can be extruded without damaging an adjacent stave or a steel shell. Become like

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of a method of removing a blast furnace stave according to the present invention, wherein (a) is a view as viewed from a longitudinal sectional direction of a stave to be removed, (b) is an AA sectional view of (a), and (c). () Is a schematic perspective view of a stave to be removed.

FIGS. 2A and 2B are views of another stave applied to the method for removing a blast furnace stave according to the present invention, as viewed from a longitudinal sectional direction.

FIG. 3 is a vertical sectional view showing a state where the stave is attached to a steel shell.

FIG. 4 is a horizontal sectional view showing a state in which a stave is attached to a steel shell.

5 (a) is a vertical sectional view after wear of the stave showing a stave mounting state having a longitudinal sectional shape whose thickness does not largely change in the height direction, and FIG. 5 (b) is an AA cross section of FIG. 5 (a). FIG.

FIG. 6A is a view in a vertical sectional direction before wear of the stave, showing an attached state of a stave having a longitudinal sectional shape whose thickness does not change greatly in a height direction, and FIG. 6B is a sectional view taken along the line AA in FIG. FIG.

FIG. 7A is a view in a vertical sectional direction after stave wear showing an attached state of a stave having a longitudinal sectional shape whose thickness greatly changes in a height direction, and FIG. 7B is a sectional view taken along the line AA in FIG. FIG.

[Explanation of symbols]

 1b Stave 1ba Interference part 1bb Thick part 1bd Cooling pipe 3 Blast furnace 3a Blast furnace steel

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Yamazaki 4-33, Kitahama, Chuo-ku, Osaka City, Osaka Prefecture Inside Sumitomo Metal Industries, Ltd. (72) Inventor Ryo Ohara 1850 Minato, Wakayama-shi, Wakayama (72) Inventor Seiichiro Hayashida 1850 Minato, Wakayama City, Wakayama Prefecture Sumitomo Metal Industries, Ltd. Wakayama Steel Works F-term (reference) 4K015 CA04 CA10

Claims (1)

[Claims] When extruding a stave into a furnace to replace a stave, a cooling pipe located at an opening of a steel bar of the stave to be replaced is cut off, and the stave to be replaced is removed from the opening of the steel bar. A method for removing a blast furnace stave, comprising separating a portion that interferes with an adjacent stave, and thereafter extruding the stave into a furnace.