JPH0629447B2 - Hot air stove inner wall brick repair method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an inner wall in the vicinity of a connecting portion between a furnace body (hereinafter simply referred to as a furnace body) such as a heat storage chamber, a combustion chamber, and a mixed cooling chamber of a hot-blast stove and a connecting pipe. It relates to a method of hot repairing bricks that have fallen off or are damaged.

[Conventional technology]

The hot-air stove that supplies hot air to the blast furnace is composed of heat-storage bricks, a combustion chamber, and a mixing / cooling chamber body, and the respective furnace bodies are connected by communication pipes.

The hot-blast stove configured in this way has a life span of 15 to 20 years, and during that period, various operations such as pressure, heat fluctuation, and behavior of the furnace body due to expansion and contraction are caused by cycle operations of combustion, heat storage, and blowing. Due to changes in conditions, furnace shells, especially inner wall bricks, are inevitably subjected to severe operating conditions, and the inner wall bricks of the furnace body or each connecting pipe or its connection part are locally dropped and damaged. . As a method for hot repairing such a local dropout or damage, for example, a method for repairing a dropout or damaged portion of a lower brick, a burner or the like of a combustion chamber is disclosed in Japanese Patent Laid-Open No.
There is a proposal in JP-A-2-29404. This consists of arranging two upper and lower heat shields (upper and lower heat shields, lower heat assembly heat shields) horizontally at the connection between the combustion chamber and the hot air communication pipe. A heat retaining temporary combustion burner is provided in the combustion chamber to forcibly cool and repair the combustion chamber below the heat shield plate.

[Problems to be solved by the invention]

According to the method disclosed in Japanese Patent Laid-Open No. 52-29404, a heat insulating plate is installed in the furnace body to shut the furnace body up and down.
When performing hot repair, it is necessary to install a temporary combustion burner that keeps the heat storage chamber and the combustion chamber warm, and the repair section that requires forced cooling covers a wide range. Therefore, it takes a long time to cool to a temperature that allows repair work, and as a result, the temperature of all sidewalls is lowered to a temperature range where repair is possible. It will be damaged due to peeling of joints between bricks due to contraction between bricks, and the entire amount will be transshipped to new bricks for repair. In addition, after this repair, the entire repair range must be preheated and heated, which requires a great deal of labor, time, and cost.

[Means for solving problems]

The present invention has been made to solve the above-mentioned problems of the prior art and to make it possible to repair only the connecting portion of the connecting pipe of the furnace body from outside the furnace body. The gist of the invention is hot air using silica bricks. When the furnace is maintained at 700 ° C or higher and the inner wall bricks at the connection between the furnace body and the connecting pipe are repaired for the falling damage,
An opening is provided in the connecting pipe, and a heat-resistant and heat-shielding member capable of expansion and contraction supported by a support arm provided outside the furnace body is in a reduced state,
After being inserted into the furnace body through the opening and expanding, the peripheral portion of the furnace body can be brought into contact with the inner wall surface of the furnace body in the vicinity of the connection portion, and then the support arm is retracted to set the heat-resistant and heat-insulating member. An inner wall of a hot-blast stove characterized by closely contacting the inner wall surface of the furnace main body, blocking radiant heat from the inside of the main body to the connecting pipe connecting portion, and repairing the inner wall brick falling damage portion of the connecting portion from outside the furnace main body It is a brick repair method.

[Action]

According to the present invention, a heat-resistant and heat-insulating member reduced from an opening formed by cutting and removing a connecting pipe is loaded into a furnace main body by a support arm, and after being expanded in the furnace main body, an inner wall around the inner opening of the furnace main body Since it adheres firmly to the heat shield and shields the required minimum of the repair target part, the time required for heat insulation is very short. Moreover, since the furnace body is not divided into upper and lower parts, it is not necessary to install a temporary combustion burner for heat retention. Despite this, 700 ° C because the existing combustion burner can be used to keep the temperature of the inner wall bricks of the main body of the furnace other than the local area near the repair section and the communication tube excluding the communication tube that has been cut and removed.
It is easy to hold the above, cracks do not occur in the brick part of the silica inner wall, joint separation between bricks does not occur, and it is possible to prevent the brick repair area from expanding in each furnace body and in the connecting pipe. Brick transshipment repair time, temperature decrease time of repair section to start repair, temperature rising time after repair, etc. are short and safe and smooth repair can be performed without workers entering the furnace at all Becomes

〔Example〕

1 to 3 are simplified explanatory views showing an embodiment of the method of the present invention, and FIGS. 1 (A) to (D) are bricks of a mixed cooling indoor wall B at the root of the mixed cooling connecting pipe 7. The side section implementation explanatory view showing a repair process is shown.

FIG. 1 (A) shows temporary equipment and mixed cooling connecting pipe cutting work. In the figure, 8 is a brick dismantling temporary receiving deck provided below the mixed cooling connecting pipe 7, and 9 is provided above the connecting pipe 7. Temporary hoist rails, 10 are temporary electric chain hoists that hang down on the rails 9, 11a and 11b are temporary heat shield blind flanges, and (a) a temporary receiving deck 8 is provided below the mixed cooling connecting pipe 7 of the hot stove to be repaired. Rail 9 with a hoist 10 hanging above it
Is installed and the hot blast stove to be repaired is cut off from another healthy hot blast stove, and the amount of gas supplied to the combustion burner below the combustion chamber 2 of the hot blast stove is adjusted to the amount of heat retaining gas for repair.

(b) The steel shell 7a and the lining brick 7b of the mixed cooling connection pipe 7 are cut, the cut portion is removed by the hoist 10, and then the temporary heat shield blind flanges 11a, 11b are conveyed by the hoist 10.

(c) The blind flanges 11a and 11b are attached to both ends of the cut of the connecting pipe 7 to prevent heat from being dissipated from the inside of the mixed cooling chamber 4 and the connecting pipe 7, and the heat shield blind plate shown in FIG. 1 (B). Makes installation work easier.

In FIG. 1 (B), 12 is a take-in rail temporary mount provided on the dismantling temporary receiving deck 8, 13 is a mounting device provided on the rail 12a, 14 is a heat-resistant block-assembled heat shield blind plate that can be expanded and contracted, 1
5 is a set chain, the blind flange 11a,
When the installation of 11b is completed, the hoist 10 is used to attach the rail 1 to the upper surface.
The take-in rail temporary mount 12 on which the 2a is arranged is conveyed onto the brick dismantling temporary receiving deck 8, and the foot portion 12b of the mount 12 is transferred to the deck 8.
It is fixed on the upper surface. The hoist 10 transports and mounts the mounting device 13 on the rail 12a, and locks the heat shield blind plate 14 on the support arm 22 of the mounting device 13 in a folded state.
After removing the blind flange 11a with the hoist 10,
The intake device 13 is moved toward the mixed cooling chamber 4 to move the heat shield blind plate 1
4 is inserted into the mixed cooling chamber 4 through the opening 16 of the connecting portion of the connecting pipe 7. After raising and lowering the heat shield blind plate 14 in the direction of the mark A, the folded portion is expanded. The mounting device 13 is retracted to move the blind plate 14
Is brought into close contact with the inner wall of the mixed cooling chamber 4, and is locked to the locking member 27 outside the chamber 4 by the set chain 15 to fix the blind plate 14.

This will be described in more detail with reference to FIGS. 2 and 3.

The mounting device 13 rotatably mounts a dolly 18 having wheels 17 that engage with the rails 12a, and a central portion on a support member 19 on the upper surface of the dolly 18, a counterweight 20 is provided at the rear portion, and a Y-shaped holding is provided at the front portion. Arm 2 provided with member 21
2 and a winch 23 provided on the upper surface of the arm 22 between the support member 19 and the counterweight 20.

As shown in FIG. 2 and FIG. 3, the heat shield blind plate 14 is provided on the circular heat shield plate 14a matching the shape of the opening 16 of the mixed cooling chamber 4 of the connecting portion of the connecting pipe 7, and on the periphery of the heat shield plate 14a. Further, the heat-resistant material fixing stud 14c having the fire-resistant heat-resistant fiber material 14b for sealing is used and can be divided into seven blocks.
This block 14-1 and 14-2 and 14-5, block 1
4-4 and 14-7, blocks 14-3 and 14-6 are connected by bolts and nuts (not shown) through the respective connecting holes 14d, and the blocks 14-3, 14-6 and the block 14 are connected.
-4 and 14-7 are connection hinges 1 on the left and right of the block 14-1.
4e is connected via a bolt and nut (not shown) so as to be foldable. The block 14-1 is provided with an opening 14f for mounting one end of the set chain 15 and slightly above the center (block 9-2 direction). An arm locking shaft 14g is provided in the above, and a hook 14h for connecting the block extracting wire 24 is fixed to each of the blocks 14-1 to 14-7.

Along with locking the arm locking shaft 14g of the heat shield blind plate 14 conveyed by the hoist 10 to the Y-shaped holding member 21 at the tip of the arm 22 of the intake device 13 configured as described above,
The wire 25 connected to the opening 14i provided in the block 14-2 of the blind plate 14 is connected to the winch 23 through the guide roller 26 provided on the upper surface of the arm 22 and wound up, and the blind plate 14 is attached to the arm 22. On the other hand, place it in a fallen state. At this time, the blocks 14-3 and 14-6 and the block 14
-4 and 14-7 are self-weighted and are folded on both sides of the block 14-1 in a hanging state via connection hinges 14e.

Thus, the truck 18 is driven and the cooling chamber 4 is opened from the opening 16.
The carriage 18 is stopped when it is loaded into the vehicle and reaches a predetermined position.
Next, when the winch 23 is rotated in the opposite direction to loosen the wire 25, the heat shield blind plate 14 sequentially turns in the direction of arrow A with the arm locking shaft 14g as a fulcrum due to its own weight and rises and falls.

When the heat shield blind plate 14 is tilted down, an operator pushes the blocks 14-3 and 14-6 and the blocks 14-4 and 14-7 which are folded by the operation rod (not shown) to spread the circular blind. After the plate 14 is formed, the carriage 18 is moved backward, and is retracted and stopped until the sealing refractory heat-resistant fiber material 14b of the blind plate 14 comes into contact with the inner wall of the mixed cooling chamber 4.

Then, the blind plate 14 in which the tip of the arm 22 is lowered and tilted down
The foot 14j provided at the bottom of the brick is placed on the upper surface of the brick 4a of the mixed cooling chamber 4.

In this state, one end of the set chain 15 communicates with the opening 14f of the block 14-1 and the other end of the chain 15 communicates with the member 27 outside the chamber 4 to connect the blind plate 14 to the mixed cooling chamber 4. Prevents falling and maintains the sealing property.

Further, the tip of the arm 22 is lowered, the Y-shaped holding member 21 at the tip of the arm 22 is disengaged from the arm locking shaft 14g, and the carriage 18 is retracted and stopped.

The take-in device 13 is taken out by the hoist 10 so as not to interfere with the subsequent brick repair work.

FIG. 1 (c) shows the brick winding repair of the brick dropout part and the removal work of the shielding blind plate 14 thereafter, 28 is a brick dropout damaged part repair brick, 29 is a protective hardware, 24 is a heat resistant wire When the attachment device 13 is removed, the brick falling part of the opening 16 is repaired.

When the repair is completed, the protective hardware 29 is laid on the lower surface of the repair brick 28, and one end of each heat resistant wire 24 is fixed to the hook 14h of each block 14-1 to 14-7.

In this state, remove the bolts and nuts that connect the blocks 14-1 to 14-7 and wire 15
Is removed from the opening 14f of the block 14-1.

Thus, each block 14-1, 14-2, ..., 14-
Workers 6 and 14-7 in this order in order of heat resistant wire 24
Is pulled out, and the upper surface of the protective metal member 29 is slid to be pulled out of the mixed cooling chamber 4.

FIG. 1 (D) shows the restoration work of the cutting part of the mixed cooling communication pipe 7, 30a to 30e are heat insulating walls, 31a to 31d are short pipes, 32a to 32d are lining bricks, and the blind plate When the disassembly and removal of 14 is completed, bricks are blind-laid in the opening 16 of the mixed cooling chamber 4 and the heat insulating wall 30 is removed.
a is formed.

After forming a lining wall 7b by laying bricks in the steel skin 7a of the mixed cooling communication pipe 7 at the root of the mixed cooling chamber 4, the short pipe 3 is connected to the communication pipe 7.
1a is welded, the bricks in the pipe 31a are piled up, and the lining wall 32a
To form.

The heat insulating wall 30a provided in the opening 16 of the mixed cooling chamber 4 is dismantled and removed, and the heat insulating wall 30b is provided at the end of the short pipe 31a.

In parallel with this, the temporary heat-insulating blind flange 11b is removed from the connecting pipe 7, a short pipe 31c is welded to the end of the connecting pipe 7, and the short pipe 31c is brick-laid to form the lining wall 32c.
To form.

Further, the short pipe 31b, the lining wall 32b, and the heat insulating wall 30c are provided in the same manner as above.

Lastly, when the short pipe 31d provided with the lining wall 32d is conveyed to the set position by the hoist 10, the heat insulating wall 30c provided at the end of the short pipe 31b is dismantled and removed, and the short pipe 3 immediately.
A short pipe 31d is inserted between 1b and 31c, and both ends are fixed to the short pipes 31b and 31c by flange fixing.

In this way, after drying the brick falling-off damaged part repair brick 28 of the mixed cooling chamber 4 opening 16 part, the lining walls 32a to 32d in each of the short-circuit pipes 31a to 31d, and the lining wall 7b in the communication pipe 7, Other healthy hot blast stoves will be connected and restarted.

In the actual cooling, an operation is performed to spread the folded blocks 14-3 and 14-6 and the blocks 14-4 and 14-7 of the heat shield blind plate 14 which is tilted in the mixed cooling chamber 4. Although a rod is used, the present invention is not limited to this, and a cylinder may be provided and expanded by the operation of the cylinder.
Further, when the heat shield blind plate 14 is taken out from the inside of the mixed cooling chamber 4, the bolts and nuts connecting the blocks 14-1 to 14-7 are removed, and the blocks 14-1 to 14-7 are separated. Although it was taken out, when the opening 16 of the mixed cooling chamber 4 is wide, the heat shield blind plate 14
It is preferable to take out the product in a folded state when it is loaded in the mixed cooling chamber 4.

Further, in this embodiment, the heat shield blind plate 1 is used as the heat resistant heat shield member.
4 is provided, but in place of this, a heat-resistant thin film, for example, a stainless thin film, or an expandable / retractable tare valve made of ceramic heat-resistant fiber is used, and the expansion / contraction can be supplied or exhausted inside the tare, or an inert gas, etc. Alternatively, the gas may be supplied or discharged.

〔The invention's effect〕

According to the method of the present invention, since the furnace body is not shut up and down in the height direction by the heat resistant heat shield member, the existing combustion burner can be diverted simply by adjusting the fuel flow rate, and it is necessary to install a temporary combustion burner for heat retention. Since it does not, the facility cost can be reduced, the construction period can be shortened, and the repair area is expanded to the inside of the furnace body and the connecting pipe of the cutting connecting pipe for local repair work near the connecting part of the hot-air stove body and the connecting pipe. Repair work can be done without repairing, heat insulation time to enter repair, cooling time of repair section, brick transshipment time and heating time after repair are shortened, repair man-hours and repair materials are significantly reduced, repair cost It is possible to shorten the repair work period comprehensively, and it is possible to carry out repair without entering the furnace at all, and the working environment is improved, which is a great effect.

[Brief description of drawings]

FIGS. 1 to 3 are views for explaining one embodiment of the method of the present invention, and FIGS. 1 (A), (B), (C), and (D) show a mixed cooling chamber of a hot stove and a mixed cooling connection. Explanatory drawing when repairing bricks at the root of the pipe, FIG. 2 is an enlarged view of the mounting device for mounting the heat-shielding blind plate of the heat-resistant block in FIG. 1, and FIG. 3 is the heat-resistant block-assembled type It is a structure explanatory view of the heat shield blind plate. 2 ... Combustion chamber, 3 ... Hot air connection pipe 4 ... Mixed cooling chamber, 7 ... Communication pipe 8 ... Brick dismantling temporary receiving deck, 9 ... Temporary hoist rail 10 ... Temporary electric chain hoist 11 ... Temporary Heat proof blind flange 12 …… Mounting rail temporary mount, 13 …… Mounting device 14 …… Heat shield, 15 …… Set chain 16 …… Opening hole, 17 …… Wheels 18 …… Truck, 19 …… Supporting member 20… … Counterweight, 21 …… Y-shaped holding member 22 …… Arm, 23 …… Winch 24 …… Block removing wire 25 …… Wire, 26 …… Guide roller 27 …… Locking member 28 …… Brick falling damage Part repair brick 29 …… Protective hardware, 30 …… Heat barrier 31 …… Short pipe, 32 …… Inner brick

Claims (1)

[Claims] 1. A hot blast stove using silica brick is maintained at 700 ° C. or higher to provide an opening in the connecting pipe when repairing an inner wall brick falling damage part of a connecting portion between the furnace body and the connecting pipe, An expandable / contractible heat-resistant and heat-insulating member supported by a support arm provided outside the furnace main body is inserted into the furnace main body through the opening in the reduced state to expand the peripheral part of the furnace around the connection part. After making it possible to contact the inner wall surface of the main body, the support arm is retracted to bring the heat-resistant and heat-insulating member into close contact with the inner wall surface of the furnace body,
A method for repairing inner wall bricks of a hot stove, characterized in that radiant heat from the inside of the main body to a connecting pipe connecting portion is shut off, and an inner wall brick falling damage portion of the connecting portion is hot repaired from outside the furnace main body.