JP2001073591A - Method for connecting branch tube to chimney - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for connecting efficiently and exactly a branch tube to a chimney discharging high-temperature exhaust gas, while keeping the inside of the chimney hardly affected by the outside air. SOLUTION: After a part of the outer wall 1 of a chimney made of reinforced concrete is cut off circularly and removed by a cylindrical body 4a of a core cutter which has a cutting bit provided in projection at the front end, a part of the inner wall 2 of the chimney B constituted of a brick wall is cut through the hole formed by the cutting-off, by the cylindrical body 4a of the cure cutter, while a block-like part of the inner wall 2 being cut off is taken into the cylindrical body 4a. Then, this block-like part of the inner wall 2 is removed, being cut up into small pieces, while a communicating hole part formed in each cutting up is shut off by a shutoff plate and the block-like part of the inner wall 2 is replaced by the shutoff plates in a plurality. A branch tube C is connected to the cylindrical body 4a in this state and then the shutoff plates are removed sequentially through the branch tube C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for connecting a branch pipe to a chimney of a coke oven or the like in a steel mill.

[0002]

2. Description of the Related Art High-temperature gas generated in a furnace such as a coke oven at an ironworks is discharged from a chimney through a pipeline. In recent years, this exhaust gas has been used effectively for heating such as heating and hot water supply. In addition, it is taken through a chimney through a branch pipe. On the other hand, if you build a new furnace,
In order to use the chimney of the existing furnace as the chimney for exhaust gas from this new furnace, the new furnace and the chimney are connected and communicated via a branch pipe, and the exhaust gases from both furnaces are merged in one chimney. Has been done.

When the above furnace is a coke oven, high-temperature exhaust gas of about 160 ° C. rises in the chimney as hot air due to a pressure difference from the outside air. In state. And the chimney has a double cylindrical structure with a refractory brick inner wall to withstand this high temperature and a reinforced concrete outer wall that serves as a strength member, and the reinforced concrete outer wall has low heat resistance and is about 80 If the substrate is constantly heated at a temperature of ° C., there is a high possibility of destruction in the future. Therefore, an air layer for heat insulation is provided between the inner wall and the outer wall.

Further, a damper as a constant air volume device is provided in a pipeline for introducing exhaust gas from the furnace to the chimney, and the damper is constant when the pressure between the furnace and the chimney is constant in a steady state. A certain amount of gas is configured to flow into the chimney through a damper maintained at an opening.

As described above, in order to connect the above-described branch pipe to a chimney in which high-temperature exhaust gas is generated as an updraft,
2. Description of the Related Art Conventionally, a through hole is opened from the outer wall side to the inner and outer walls of a chimney using a crusher such as a breaker, and thereafter, an end of a branch pipe is inserted and connected into the through hole.

[0006]

However, in such a method, it takes a long time to drill a through hole, and after forming the through hole, an end of a branch pipe can be attached to the through hole. Correction work is required, and then the end of the branch pipe is inserted into the through-hole. Therefore, there is a problem that the work efficiency is poor and the construction takes a long time.

Further, the branch pipe is usually attached to the lower part of the chimney at the lower part of the chimney. If a through-hole for connecting the branch pipe is provided in this part, outside air flows into the chimney which is in a negative pressure state. As the pressure approaches the positive pressure, the pressure balance between the inside of the chimney and the inside of the furnace is lost, and the amount of gas generated in the furnace flowing into the chimney side decreases. In the furnace, as well as during operation, combustion continues even during pauses, and gas is continuously generated, so when the amount of outflow of generated gas in the furnace decreases, gas stays in the furnace and becomes a high pressure state In addition, not only does the furnace itself suffer damage, but in the case of a coke oven, the quality of the produced coke deteriorates. For this reason, the setting of the opening degree of the damper may be changed, but the work is troublesome, and there is a problem that the response to the pressure in the chimney has a time delay and it is not possible to appropriately cope with the response.

The present invention has been made in view of such a problem, and an object thereof is to pay attention to the fact that the inner wall of the chimney is a brick wall which can be dismantled by hand, and after the outer wall is cut off. The inner wall is dismantled by a method that hardly causes a pressure change in the chimney, and the work can be performed efficiently and accurately, and the connecting work of the branch pipe can be performed in a short time. It is an object of the present invention to provide a method for connecting a branch pipe to a chimney so that high heat is not transmitted from the pipe to the chimney outer wall.

[0009]

According to a first aspect of the present invention, there is provided a method for connecting a branch pipe to a chimney, the method comprising the steps of: A method in which a branch pipe is connected to a chimney provided with an inner wall in a state in which hot air is rising in a chimney, and the above-mentioned chimney is formed by a core cutter having a bit protruding from a front end of a cylindrical body. Cutting and removing the outer wall to form a drilled portion reaching the outer peripheral surface of the inner wall, and following this process, the inner wall continuous with the drilled portion is penetrated from the outer peripheral surface to the inner peripheral surface by the cylindrical body of the core cutter. And the step of storing the cut block-shaped inner wall portion in a cylindrical body and leaving the cylindrical body in a state of being penetrated between the inner and outer walls,
After this step, disassembling the block-shaped inner wall portion in the cylindrical body while dividing the block-shaped inner wall portion into several parts and sequentially forming divided communication holes leading to the smoke path, disassembling and removing the entire block-shaped inner wall portion, The step of replacing the block-shaped inner wall portion by a plurality of cut-off plates for completely closing the inside of the cylinder by closing the split communication hole portion with a cut-off plate each time the split communication hole portion is formed, A step of inserting a short pipe into the cylindrical body and forming a heat insulating layer in an annular gap between the short pipe and the cylindrical body; a step of connecting a branch pipe to the short pipe; And removing the shut-off plate sequentially from the small-area opening through the branch pipe through the small-area opening.

[0010]

A cylindrical cutter is formed by abutting a front end face of a cylindrical cutter on a predetermined portion of an outer peripheral surface of a reinforced concrete outer wall of a chimney, preferably a part of a lower end portion of the outer peripheral surface, with a bit protruding from a front end of the cylindrical body. When the body is rotated and propelled in the direction across the chimney, first, the chimney outer wall is cut into a circular groove by the front end bit of the cylindrical body of the core cutter, and the outer wall portion surrounded by the circular groove-shaped cutting portion is cylindrical. When the front end bit of the cylindrical body reaches the inner peripheral surface of the outer wall, the circular groove-shaped cutting portion penetrates the inner peripheral surface of the outer wall, the outer wall portion surrounded by the cutting portion is hollowed out, and the cylindrical portion is hollowed out. It will be stored in the body. When a part of the outer wall is cut between the inner and outer peripheral surfaces by the core cutter in this way, the core cutter is once retracted, extracted from the outer wall, and the cut outer wall portion housed therein is removed from the cylindrical body.

Next, the cylindrical body of the core cutter is inserted into a circular hole formed in a part of the outer wall by cutting the core cutter, and the front end bit thereof is brought into contact with the outer peripheral surface of the inner wall of the chimney. When a part of the refractory brick inner wall is cut in a circular shape from the outer peripheral surface of the inner wall toward the inner peripheral surface in the same manner as in the case of above, when the front end of the cylindrical body penetrates into the inner wall, Stop cutting work. In this state, a part of the cut inner wall is taken into the cylinder as a block-shaped inner wall.

Thereafter, the rear end of the cylindrical body of the core cutter is removed together with the rotating shaft, and only the cylindrical body is left in a state of penetrating between the inner and outer walls of the chimney. The block-shaped inner wall portion is manually dismantled and removed outside the outer wall through the cylindrical body, thereby connecting the flue in the chimney to the outside through the cylindrical body.

At this time, the disassembly of the block-shaped inner wall portion is performed while the block-shaped inner wall portion is subdivided into several parts, and the divided communication holes generated by removing one divided portion are immediately closed by a shutoff plate. It has little effect on the pressure in the chimney. As described above, each time a divided communication hole is formed in the block-shaped inner wall, the operation of closing the hole with the cut-off plate is repeatedly performed, and the block-shaped inner wall is replaced with a plurality of cut-off plates.

Next, the connecting short pipe of the branch pipe is inserted into the cylindrical body until the front end thereof reaches the outer peripheral portion of the inner wall, and then a gap between the short pipe and the cylindrical body is filled with a heat insulating material to form a heat insulating layer. Is formed, and then the branch pipe is connected to the short pipe. The inside and the outside of the branch pipe are in communication with each other, for example, through an opening of a valve provided in the branch pipe. Through this opening, an operator enters the branch pipe from the branch pipe into the short pipe and removes one piece of the shut-off plate. Each time, it is decomposed and discharged to the outside through the opening. At this time, if the opening of the opening is large, a large amount of outside air flows into the branch pipe, flows out into the chimney through the communication hole formed by removing the shut-off plate, and as described above, the pressure inside the chimney increases. Therefore, dust may be generated in the pipe and the working environment may be degraded and dangerous. Therefore, the operation of removing the shut-off plate is performed by minimizing the opening of the opening.

When all of the cut-off plates have been removed, a pipe is connected to the branch pipe to use the high heat of the exhaust gas in the chimney for heating, hot water supply, or the like, or the pipe is connected to a new furnace to install the pipe. Exhaust gas from the furnace is introduced into the chimney, combined with exhaust gas from the existing furnace and discharged.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an existing coke oven.
The exhaust gas from the A ₁ connects the branch tube C to the lower end position of the existing chimney B for releasing to the atmosphere, the coke oven gas of A ₂ in new through the branch pipe C and the pipe G into the chimney B It flowed, in which is combined with the exhaust gas of existing coke oven a ₁ shows the entire equipment structure are configured to emit to the outside, connected between existing coke oven a ₁ and the chimney lower end, communicates A constant-flow damper E is provided in the exhaust gas pipe D, and the branch pipe C is connected to a new coke oven through an opening / closing valve F.
It is connected to the pipe G communicating with A _2. The above chimney B
Is a cylindrical outer wall 1 made of reinforced concrete as shown in FIG.
And has a double tubular structure with a refractory brick tubular inner wall 2,
A gap 3 is provided between the inner and outer walls 1 and 2 to prevent heat from being transmitted from the inner wall 2 to the outer wall 1 by a fresh air layer rising in the gap 3.

[0017] Thus, in order to share the chimney B of existing coke oven A ₁ as newly established exhaust chimney of the coke oven A _2, it is necessary to connect the branch pipe C to the chimney B as described above Hereinafter, a method of connecting the branch pipe C will be described in detail. First, a scaffold 15 is assembled as shown in FIG.
The gantry 16 is fixed on the gantry 15, and the rotation and propulsion drive device 17 of the core cutter 4 is installed on the gantry 16. The core cutter 4 has an inner diameter slightly larger than the outer diameter of the branch pipe C and a length slightly longer than the thickness between the outer peripheral surface of the outer wall 1 and the inner peripheral surface of the inner wall 2 of the chimney B. A large number of cutting bits 4b are protruded from the front end side opening end surface of the formed cylindrical body 4a, and the cylindrical body 4a of the core cutter 4 is placed on the front end of the scaffold 15 facing the outer peripheral surface of the chimney B. The lower peripheral surface of the roller 18 is supported on a plurality of rollers 18 rotatably supported in a rotatable manner.

Further, an outer peripheral edge of an annular flange plate 4c is detachably fixed to an opening end on the rear end side of the cylindrical body 4a of the core cutter 4, and at the center of the rear surface of the flange portion 4c,
A mounting plate 20 fixed to the front end of the rotating shaft 19 is detachably fixed by bolts or the like, and the rear end of the rotating shaft 19 is connected to the rotation and propulsion drive device 17 via the rotating shaft 19. The rotation and the driving force of the propulsion drive device 17 are transmitted to the core cutter 4.

[0019] Then, the existing coke oven A ₁ is in the running, perform the task of providing the drilling portion by cutting a part of the outer wall 1 of the chimney B. First, the rotation and propulsion drive device 17 is operated to push the rotating shaft 19 so that the front end face of the cylindrical body 4a of the core cutter 4 is brought into contact with a predetermined portion on the outer peripheral surface of the lower end portion of the outer wall 1 of the chimney B. In this state, when the cylindrical body 4a of the core cutter 4 is propelled while being rotated by the rotation and propulsion drive device 17, the reinforced concrete outer wall 1 of the chimney B is formed by the cutting bit 4b projecting from the front end face of the cylindrical body 4a. As shown in FIG. 3, the outer wall 1 is cut 5 in a circular groove shape in the thickness direction, that is, toward the inner peripheral surface.
As 4a penetrates into the outer wall 1, its circular groove-shaped cutting portion 5
Outer wall portion surrounded by the cutting portion 5 with increasing depth
1a is taken into the cylindrical body 4a, and the front end of the cylindrical body 4a reaches the inner peripheral surface of the outer wall 1 and protrudes into the gap 3 between the outer wall 1 and the inner wall 2 as shown in FIG. Then, the cutting portion 5 completely penetrates the outer wall 1 and the outer wall portion 1a surrounded by the circular cutting portion 5 is cut out, separated from the surrounding wall portion and housed in the cylindrical body 4a. Become.

As described above, a part of the outer wall 1 is
When the cutting is performed across the inner and outer peripheral surfaces, the rotation and propulsion drive device 17 is operated in the reverse direction to retract the rotating shaft 19 in the retreating direction, and the cylindrical body 4a of the core cutter 4 is extracted from the outer wall 1 and then removed. The outer wall portion 1a housed in the cylindrical body 4a is removed from the cylindrical body 4a.

Thereafter, the rotation and propulsion drive unit 17 is again turned on.
When the cylinder 4a of the core cutter 4 is propelled toward the chimney B by operating the cylinder 4, the cylinder 4a follows the same trajectory as when the cylinder 4a was first propelled on the roller 18, and is propelled by the cutout of the outer wall portion. It is accurately inserted into the formed circular hole 6 (shown in FIG. 5). A cylindrical body 4a is formed in the drilled portion 6.
When the front end face of the cylindrical body 4a comes into contact with the outer peripheral surface of the inner wall 2 made of brick, the cylindrical body 4a is further rotated. A part of the inner wall 2 facing the extension of the hole 6 is cut in a circular groove shape having the same shape and the same size as the cutting part 5 when drilling the hole 6 from the outer peripheral surface toward the inner peripheral surface. The part 5a is cut.

When the cutting portion 5a reaches the inner peripheral surface of the inner wall 2 and the front end of the cylindrical body 4a of the core cutter 4 projects into the chimney B of the chimney B, the cutting portion 5a completely penetrates the inner wall 2. Then, the inner wall portion 2a surrounded by the circular cutting portion 5a is hollowed out in a circular block shape, separated from the surrounding wall portion, and the circular block-shaped inner wall portion 2A is formed into a cylindrical body as shown in FIG. 4a is housed in the first half.

When a part of the inner wall 2 is cut into a circular block shape by the cylindrical body 4a of the core cutter 4, the rotation and propulsion drive unit 17 is stopped, and the front end mounting plate 20 of the rotation shaft 19 is removed. The flange plate 4c is fixed to the base end side opening end of the cylindrical body 4a, and the flange plate 4c is also removed from the rear end surface of the cylindrical body 4a to completely open the rear end of the cylindrical body 4a. Only body 4a is inside and outside wall 1, 2
It is left in a state of being penetrated in between.

Next, the operation proceeds to the work of removing the circular block-shaped inner wall portion 2A housed in the cylindrical body 4a. In this case, when removing the circular block inner wall portion 2A, since the smoke path b chimney B is ambient air communicating through the cylindrical body 4a, during the dismantling once the existing coke oven A _1, halting. Be rested coke oven A _1, not endured has continued combustion in the furnace and the hot gas is generated, since the inside chimney B hot air due to exhaust gas occurs as updraft and the chimney B The pressure becomes negative with respect to the outside, and the outside air flows into the chimney B due to the pressure difference with the outside air. A so-called draft occurs, and the pressure balance between the chimney B and the existing coke oven A ₁ is lost, and the existing coke oven A ₁ since it becomes small inflow of the exhaust gas to the chimney B leads to degradation of coke or damage the existing coke oven a _1, as much as possible reduce the opening time of the cylinder 4a for communicating the inside of the chimney B to the outside air, and a cylindrical The opening of the body 4a is minimized so that the pressure in the chimney B hardly fluctuates.

For this reason, the circular block-shaped inner wall portion 2A in the cylindrical body 4a that blocks the chimney B from the outside air is removed while being divided into several portions, and the divided communication holes 7a to 7a formed by the removal are removed. Repeat the work of closing 7d immediately.
This work will be described in detail. First, as shown in FIG.
A steel cylindrical frame 8 that can be inserted into 4a is used. The cylindrical frame 8 is connected between the front and rear circular frames 8a and 8b by a plurality of straight members 8c having a fixed length, and the front circular frame 8a has a fan-shaped opening having the same area by the divided frame 8d. 81-84
Is divided into a plurality of parts (four in the figure).

The cylindrical frame 8 is inserted into the cylindrical body 4a so that the front circular frame 8a is brought into contact with the outer surface of the block-shaped inner wall 2A. The worker dismantles and removes the refractory brick of the block-shaped inner wall portion 2A in the cylindrical body 4a exposed through the fan-shape into the block-shaped inner wall portion 2A as shown in FIG. 8 by using an appropriate tool. The communication hole 7a is opened. This divided communication hole 7a
Is provided, a fan-shaped cut-off plate 9a having the same shape as the fan-shaped opening 81 is immediately applied to the fan-shaped opening 81 of the cylindrical frame 8, and straight edges on both sides of the cut-off plate 9a are divided into frame members. 8d, the fan-shaped divided communication hole portion 7a is temporarily fixed to the
Close up. The temporary fixing may be performed by using a U-shaped metal fitting or the like which clamps the divided frame member 8d and the back surface of the edge portion of the cutoff plate 9a with screws.

After one sector-shaped divided communication hole 7a is formed in the block-shaped inner wall 2A in the cylindrical body 4a, the refractory brick of the block-shaped inner wall 2A exposed through the next sector-shaped opening 82 is removed. After disassembly and removal to provide the sector-shaped divided communication hole 7b, the sector-shaped divided communication hole 7b is
Thereafter, the work is repeated by disassembling and removing the block-shaped inner wall portion 2A facing these openings through all the fan-shaped openings 81 to 84 of the cylindrical frame 8 and closing the work by the closing plate 9a. Then, as shown in FIG. 9, the block-shaped inner wall portion 2A in the cylindrical body 4a is completely dismantled and removed, and the cylindrical body 4a is removed.
The front half of the cylinder 4a is fully opened to communicate with the chimney B of the chimney B, and the middle part of the cylindrical body 4a is entirely formed by the disc-shaped cut-off wall 9 assembled by the plurality of fan-shaped cut-off plates 9a. The structure is so closed that the inside of the chimney B of the chimney B communicates with the space in the rear half of the cylindrical body 4a in which the cylindrical frame 8 is inserted.

The block-like inner wall portion in the cylindrical body 4a
When disassembling and removing 2A, the fan-shaped openings 81 to 84 of the cylindrical frame 8 are closed in advance with a closing plate 9a while leaving one fan-shaped opening 81, and the fan-shaped openings 81 to 84 are removed. A block-shaped inner wall portion facing the opening 81 through the opening 81
After dismantling and removing a part of 2A to form a fan-shaped communication hole 7a, the cylindrical frame 8 is rotated in the circumferential direction (90 degrees in the figure) in the cylindrical body 4a, and Fan-shaped communication hole 7a
Next block-shaped inner wall facing the opening 81
A part of 2A is dismantled and removed, and the cylindrical frame 8 is again rotated to close the communication hole 7b of the dismantlement and removal trace with the shut-off plate 9a. After repeating this work, the dismantling and removal is finally performed. The formed communication hole 7d is closed by mounting the fan-shaped shut-off plate 2a in the fan-shaped opening 84 of the cylindrical frame 8 to form a shut-off wall 9 in which the intermediate portion in the cylindrical body 4a is completely closed. Is also good. Cylindrical body
When the 4a is entirely blocked by the deadline wall 9, no possibility that outside air from entering the chimney B also operate the coke oven A ₁ of the existing.

As described above, since the block-shaped inner wall portion 2A in the cylindrical body 4a is made of a brick wall, it can be dismantled and removed by hand, unlike the outer wall 1 made of reinforced concrete. Since the communication holes 7a to 7d are sequentially closed by the cutoff plate 2a each time the communication holes 7a to 7d having a small cross section are formed by opening the holes in small portions, the pressure in the chimney B is almost fluctuated. In addition, the working environment is improved without the generation of dust due to the circulation of outside air, the work can be performed safely, and the brick is manually dismantled and removed, so that the work can be performed accurately and reliably.

After the communication between the chimney B and the flue b to the outside through the inside of the cylinder 4a is cut off by the closing wall 9, the outside diameter of the inside of the cylinder 4a is reduced as shown in FIG. Inserts the short pipe 10 having a diameter slightly smaller than the inner diameter of the cylindrical body 4a. The front and rear ends of the short tube 10 are entirely open, and a connecting flange 10a is integrally provided at the rear end. The operation of inserting the short pipe 10 is performed by using the rotation and propulsion drive device 17 described above, and the roller 18 provided on the scaffold 15 is replaced with a large-diameter roller (not shown). The center of the short pipe 10 placed on the
4a to match the center of the
As a result, the short pipe 10 is propelled, and the front end face of the opening of the short pipe 10 is brought into contact with the back surface of the cutoff wall 9. Further, by pushing the short pipe 10, the cut-off wall 9 is moved forward together with the cylindrical frame 8 in the cylindrical body 4a toward the chimney B side of the chimney B, and the cut-off wall 9 is moved in the front half rear of the cylindrical body 4a. That is, it stops at the position where it reaches the inner wall 2 side of the chimney B.

Next, castables are injected into and filled in an annular gap between the inner peripheral surface of the cylindrical body 4a and the outer peripheral surface of the short pipe 10, and the castables are solidified to form a cylindrical body as shown in FIG. A heat insulating layer 11 made of a castable refractory in which the short pipe 4a and the short pipe 10 are integrally fixed is provided, while a gypsum board is applied to the outer peripheral surface of the rear end of the short pipe 10 projecting outward from the outer wall 1 of the chimney B. After the heat insulating layer 12 is formed by applying, a formwork (not shown) is assembled around the heat insulating layer 12 and concrete is poured into the formwork to form a chimney B around the short pipe 10. A reinforced concrete layer 13 integrated with a part of the outer wall 1 is formed.

Thereafter, as shown in FIG. 12, a fixed length branch pipe C connecting the valve F to the rear end is connected to the rear end flange portion 10a of the short pipe 10. The branch pipe C can be connected using the scaffold 15 from which the rotation and propulsion drive device 17 has been removed. Next, the valve F is opened to the minimum necessary amount corresponding to substantially the same opening area as one fan-shaped communication hole portion 7a when the block-shaped inner wall portion 2A is dismantled, and an operator opens the branch pipe C from the opening portion. And a fan-shaped cut-off plate forming a cut-off wall 9 by entering the short pipe 10 from the branch pipe C.
9a is removed to open the fan-shaped opening 81 of the cylindrical frame 8, and the shut-off plate 9a is removed from the inside of the branch pipe C to the outside through the opening of the valve F. During the dismantling of the deadline plate 9a is temporarily existing coke oven A _1, allowed to rest.

As shown in FIG. 13, all the cutoff plates 9a are removed, and as shown in FIG. 13, the chimney B passes through the open end of the cylindrical frame 8 having the short pipe 10 fully opened and the communication hole 7 in the front end of the cylindrical body 4a. Flue b
When the coke oven A ₂ is connected to the new coke oven A ₂ , the valve F is closed to operate the existing coke oven A ₁ while the pipe G is connected to the branch pipe C via the valve F.
Chimney connection, after communicated, the valve branch pipe of the exhaust gas of the new coke oven A ₂ and by running the coke oven A ₂ from the pipe G with opening the F C, short pipe 10, through the cylindrical body 4a in to flow into the smoke oven b of B, it is combined with the exhaust gas from the coke oven a ₁ of the existing evacuated through with smoke passage b.

At this time, the front end of the short pipe 10 is connected to the inner wall 2 of the chimney B.
Side, and the heat insulating layer 11 is provided between the outer peripheral surface and the inner peripheral surface of the cylindrical body 4a, so that the heat of the high-temperature exhaust gas flowing into the chimney B through the branch pipe C is almost transmitted to the outer wall 1. On the other hand, the high-temperature exhaust gas on the side of the chimney B of the chimney B transfers heat to the cylindrical body 4a, but is cooled by the airflow rising in the gap 3 provided between the inner and outer walls 1 and 2 of the chimney B. To the outside wall 1 side.

Although the closing plate 9a is removed through the opening of the valve F, an opening / closing door formed with the minimum necessary small cross-section opening is provided in the branch pipe without using the valve F. The removal of the closing plate 9a may be performed while opening the lever opening / closing door only when the worker passes. Further, in the above embodiment, the branch pipe C attached to the chimney B is used for exhaust gas of the new furnace. However, the high temperature exhaust gas in the chimney B is taken in through the branch pipe C, and the indoor heating and hot water supply of the building are performed. May be used for heating.

[0036]

As described above, according to the method for connecting a branch pipe to a chimney of the present invention, a chimney in which a brick wall is disposed inside a reinforced concrete outer wall through an air layer, and A method of connecting a branch pipe in a state where hot air is rising, first, the outer wall of the chimney is cut and removed by a core cutter having a bit protruding at the front end of the cylindrical body, and the outer wall of the inner wall is removed. Because it forms a drilled part that reaches
The drilled part can be formed by efficiently and accurately cutting the outer wall made of reinforced concrete that is difficult to dismantle by hand with a core cutter, and then the inner wall continuous with the drilled part is formed from the outer peripheral surface to the inner peripheral surface by the core of the core cutter. The inner wall of the chimney is the same as the outer wall, since the cut inner wall portion is housed in a cylindrical body and the cylindrical body is left penetrating between the inner and outer walls. Not only can it be cut efficiently and accurately, but since the core of the core cutter is penetrated through the inner and outer walls of the chimney, but the cut block-shaped inner wall is housed in the cylinder, the outside air enters the chimney. Inflow can be reliably prevented.

Thereafter, the block-shaped inner wall portion in the cylindrical body is disassembled while being divided into small portions, and divided communication holes are formed sequentially in the flue so that the entire block-shaped inner wall portion is disassembled and removed. At the same time, each time a divided communication hole is formed, the block-shaped inner wall portion is closed by closing the divided communication hole with a cut-off plate, and the block-shaped inner wall portion is replaced with a plurality of cut-off plates for completely closing the inside of the cylinder. Since the inner wall is made of a brick wall, unlike the outer wall made of reinforced concrete, not only can it be manually dismantled and removed, but also it can be performed reliably and accurately while visually observing the dismantled state. Each time a small opening is made in the split state to form a communication hole with a small cross section, these communication holes are sequentially closed by the closing plate, so that the pressure in the chimney hardly fluctuates, and the normal Gas can be continue, also, the generation of dust due to outside air flowing into the cylinder body even working environment becomes good and without perform work safely.

Further, after replacing the block-shaped inner wall portion with the cut-off plate, a short pipe is inserted into the cylindrical body and a heat insulating layer is formed in an annular gap between the short pipe and the cylindrical body. The transmission of the heat of the high-temperature exhaust gas to the outer wall of the chimney made of reinforced concrete can be reliably blocked, and the outer wall can be prevented from being damaged. In addition, since the branch pipe is connected to the short pipe, the branch pipe connection operation can be performed quickly and accurately by using the cylindrical body as one member for attaching the branch pipe. After the branch pipe is connected, the branch pipe and the outside are communicated through the small-area opening, and the shut-off plate is sequentially removed from the small-area opening through the inside of the branch pipe. The amount of outside air flowing into the stack can be reduced to suppress a large pressure fluctuation in the chimney.

[Brief description of the drawings]

FIG. 1 is a simplified side view showing the entire configuration of a new and existing coke oven and a chimney;

FIG. 2 is a side view of an entire apparatus for forming a branch pipe connection hole in a part of a chimney;

FIG. 3 is a simplified longitudinal side view of a state in which an outer wall of a chimney is being cut by a core cutter.

FIG. 4 is a simplified vertical sectional side view showing a state where cutting of an outer wall has been completed;

FIG. 5 is a simplified longitudinal side view of a drilled portion,

FIG. 6 is a simplified vertical sectional side view of a state in which a cylindrical body of a core cutter is penetrated to an inner wall of a chimney.

FIG. 7 is a simplified perspective view of a cylindrical frame,

FIG. 8 is a simplified longitudinal sectional side view of a state in which bricks on the inner wall of a chimney are removed using a cylindrical frame, and the removal trace is closed by a partition plate;

FIG. 9 is a simplified longitudinal side view in a state where the partition is completely covered by a partition wall in a cylindrical body;

FIG. 10 is a simplified longitudinal side view of a state where a short tube is inserted into a cylindrical body and a heat insulating layer is formed.

FIG. 11 is an enlarged vertical sectional front view thereof,

FIG. 12 is a simplified longitudinal side view of a state in which a partition plate has been removed,

FIG. 13 is a simplified vertical sectional side view showing a branch pipe construction state after removal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Outer wall 2 Inner wall 2A Block-shaped inner wall part 3 Clearance 4 Core cutter 4a Cylindrical body 5 Cutting part 6 Drilling part 7a-7d Dividing communication hole part 9a Closing plate 10 Short pipe 11, 12 Heat insulation layer 13 Reinforced concrete layer A ₁ A ₂ New coke oven B Chimney C Branch pipe

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hisashi Tazaki 1-1, Hibata-cho, Tobata-ku, Kitakyushu-shi, Fukuoka Prefecture Inside Nippon Steel Corporation Yawata Works (72) Inventor Tatsuhiro Furusaga Matsuzaki, Abeno-ku, Osaka-shi 2-2-2, Machimachi, Okumura Gumi (72) Inventor Koki Matsumoto 2-2-2, Matsuzaki-cho, Abeno-ku, Osaka-shi Co., Ltd.Kunihiko Koga, Matsuzaki-cho, Abeno-ku, Osaka-shi 2-chome No.2-2 Stock Company Okumura Guminai F-term (reference) 3H019 BA24 BB04 BB09 BD03 BD05

Claims (1)

[Claims] 1. A method of connecting a branch pipe to a chimney in which a brick wall is disposed inside a reinforced concrete outer wall via an air layer in a state where hot air is rising in a flue. A step of cutting and removing the outer wall of the chimney by a core cutter having a bit protruding from the front end of the cylindrical body to form a drilled portion reaching the outer peripheral surface of the inner wall; and following this step, the cylindrical body of the core cutter By cutting the inner wall continuous with the drilled part until it penetrates from the outer peripheral surface to the inner peripheral surface,
A step of storing the cut block-shaped inner wall portion in a cylindrical body and leaving the cylindrical body penetrated between the inner and outer walls, and after this step, the block-shaped inner wall portion in the cylindrical body is divided into several parts. A step of disassembling and disassembling the entire block-shaped inner wall portion by sequentially disassembling and forming the divided communication holes leading to the inside of the smoke passage, and removing the divided communication holes each time the divided communication hole is formed. A step of replacing the block-shaped inner wall portion by closing with a cut-off plate with a plurality of cut-off plates for completely closing the inside of the cylindrical body, and inserting a short pipe into the cylindrical body and forming the short pipe and the cylindrical body. A step of forming a heat insulating layer in the annular gap between the two, a step of connecting a branch pipe to the short pipe, and a step of connecting the branch pipe to the outside through a small-area opening to allow the branch pipe to communicate with the inside of the branch pipe. Through the step of sequentially removing the cut-off plate Branch connection to the chimney characterized by.