JP2000088177A - Gas cutoff construction method using bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas cutoff construction method using a bag to prevent inflow of gas to a working region when an existing line, especially, a high pressure line is repaired. SOLUTION: A small communication hole is arranged in a given position situated upper stream from the spot to be repaired of a line 1. Thereafter, a twin type consisting of first and second bags 41 and 42 is introduced toward a post situated upper stream of a line to expand the twin type. Thereafter, gas flowing in a space part between the first and second bags is discharged to the outside of the line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shut-off method and a gas shut-off device for shutting off gas flowing through a high-pressure pipe using a bag.

[0002]

2. Description of the Related Art Conventionally, as an example of means for repairing a gas pipeline laid underground, a construction method as shown in FIG. 4 is performed. First, a work pit is formed by excavating the area around a repair target location where a leak or the like has occurred. Next, a communication hole B for introducing the airbag A into the pipeline L is opened on the upstream side and the downstream side of the repair target location X, and the airbag A is contracted from the communication hole B in the pipeline. After the introduction is completed, the airbag A is inflated in the pipeline to cut off the gas flow. A communication hole D for forming a bypass pipe C is formed outside the position of the airbag A,
After the communication hole D is connected by the bypass pipe C and the supply of gas is secured, repair work is performed.

[0003]

When the above-mentioned repair method is applied to a high-pressure pipe, the gas pressure is so high that the bag cannot be completely sealed in some cases. For this reason, the gas that has passed through the bag (overgas) flows into the repair area, and the operation becomes very dangerous. Furthermore, if the gas is heavy, the gas will settle in the work pit, giving the worker an additional danger.

The present invention has been proposed in order to cope with such a situation. When repairing an existing pipeline, particularly a high-pressure pipeline, a gas shut-off using a bag that does not allow gas to flow into a work area. It is an object to provide a construction method and a bag device.

[0005]

According to a first aspect of the present invention, in order to achieve the above object, the present invention relates to a method of shutting down an existing pipeline, which is capable of expanding and contracting upstream of a repair target portion of the pipeline. In a gas blocking method using a bag that introduces a new bag and inflates the bag to cut off the gas flow, a small-diameter communication hole is provided at a required position upstream of the repair target point in the pipeline, Introducing a double bag composed of a first bag and a second bag into the pipe through the communication hole toward the upstream side of the pipe to inflate the double bag, The gas flowing into the space between the first bag and the second bag is discharged out of the pipeline.

A bag device according to a second aspect is provided with a first
A first bag having a bag and a second bag at a subsequent stage, one end facing the first bag and the other end communicating with the air pump;
An air passage and a second air passage having one end facing inside the second bag and the other end communicating with the air pump are provided so that each bag can be independently expanded and contracted. A gas discharge passage, one end of which is provided in a space between the airbag and the bag, is provided.

According to a third aspect of the present invention, the other end of the gas discharge passage according to the second aspect communicates with a deodorizing device having an activated carbon layer, and a blower communicates with the deodorizing device.
The gas remaining in the space between the bag and the second bag is deodorized and is forcibly discharged to the atmosphere.

[0008]

According to the first aspect of the present invention, a double bag composed of the first bag and the second bag is introduced into the pipeline, and the bag is inflated to shut off gas. Even if the gas flows into the space between the first bag and the second bag over the first bag, the overgas is discharged out of the pipeline. Therefore, gas does not flow into the repair work area, and work safety is ensured.

According to the second aspect of the present invention, since the airbag introduced into the pipe is of a double type consisting of the first bag and the second bag, the efficiency of shutting off gas can be increased. In addition, since the first bag and the second bag inflate and contract in independent air passages, even if one of them is damaged, it does not affect the other. Further, if the gas passes over the first bag and the first bag and the second bag
Even when the gas flows into the space between the bag and the bag, the overgas can be discharged out of the pipeline through the gas discharge passage.

According to the third aspect of the present invention, since the gas discharged from the discharge passage is discharged through the deodorizing device, the odorant such as TBM, DMS, and THT is removed and discharged. become. Therefore, there is no complaint from the residents around the construction site. Further, since the blower is connected to the deodorizing device, the gas can be forcibly discharged by the negative pressure effect.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of the gas shut-off method of the present invention.
In the figure, reference numeral 1 denotes an existing high-pressure pipeline 1 to be repaired, in which the upstream and downstream sides of the repair location are shut off in order to repair a required portion of the high-pressure pipeline 1, and the bypass pipe 2 is moved upstream and downstream from the shut-off position. It communicates downstream and performs repair work.

First, the bag introducing device 3 is installed in the communication holes 11 on the upstream side and the downstream side of the repair point of the high-pressure pipe 1.
The communication hole 11 may be an existing opening from which a diffuser tube or the like is removed, or a newly opened opening. As shown in FIG. 2, the bag introducing device 3 includes a pedestal 31 installed on the high-pressure pipeline 1, a shutter device 32 provided on the pedestal 31, and a double bag introducing pipe 34.
a and a bag introduction pipe 33a.

The pedestal 31 has a dual bag introduction pipe hole 34 and a bag introduction pipe hole 33 which are respectively opened in a slanting manner to face each other. In FIG. 2, the double bag introduction pipe 34 a opens toward the downstream side of the high pressure pipeline 1, and the bag introduction pipe hole 33 opens toward the upstream side of the high pressure pipeline 1. ing. Although not shown, the pedestal 31 installed on the upstream side of the high-pressure line 1 has a double bag introduction pipe 34 a opened toward the upstream side of the high-pressure line 1. The bag introduction pipe hole 33 is open toward the downstream side. By doing so, each bag can be smoothly introduced into the upstream side and the downstream side of the pipeline 1.

Next, the double bag 4 will be described in detail with reference to FIG. As shown in FIG.
Has a first bag 41 at the front stage and a second bag 42 at the rear stage. The first bag 41 and the second bag 42 are formed of a material having a certain elasticity, such as a rubberized nylon base cloth, and are folded in a flag shape when contracted.

A first air hose 43 having one end facing the inside of the first bag 21 and the other end communicating with the air pump is connected to the first bag 41 while maintaining airtightness.
Supply and suction of air from the air hose 43 causes the first bag 4
1 is configured to expand and contract. Similarly, the second bag 42 has one end facing the inside of the second bag 42 and the other end communicating with the air pump.
Are connected while maintaining airtightness, and the second air hose 4
The second bag 42 is configured to be inflated and contracted by the supply and suction of air from the fourth bag 4.

Further, a suction hose 45 having one end protruding is arranged between the first bag 41 and the second bag 42. By providing this suction hose 45,
The gas flowing into the space between the first bag 41 and the second bag can be discharged out of the tube. Therefore, the danger of work can be avoided without gas flowing into the repair section.

As described above, the double bag is connected to the first bag 4.
By comprising the first and second bags 42, it is possible to improve the cutoff of gas flow in the pipeline. Further, since the first bag 41 and the second bag 42 are inflated and contracted by the independent air hoses 23 and 24, even if one of them is damaged, it does not affect the other. Further, the first air hose 4 is provided in the second air hose 44.
Since the suction hose 45 is inserted through the third and second air hoses 43, there is only one appearance-like hose, and the suction hose 45 and the first air hose 43 interfere with the bag in the pipeline. That is, the first bag 41 and the second bag 42 properly adhere to the inner wall surface of the pipeline.

Next, a gas shutoff method using the bag constructed as described above will be described in detail with reference to FIG. First, from the bag introducing device 3 installed on the upstream side of the high pressure line 1,
Open the shutter device 32 and introduce the double bag introduction pipe 3
The double bag 4 is introduced to the upstream side of the pipeline 1 using 4a. Next, the normal bag 5 is introduced toward the downstream side of the pipeline 1 by using the bag introduction pipe 33a from the bag introduction device 3 in the same manner. Then, the first bag 41 is inflated using an air pump (not shown), and then the second bag 42 is inflated. Next, the bag 5 is inflated using an air pump.

Similarly, the shutter device 32 is opened by the bag introducing device 3 installed on the downstream side of the high-pressure line 1 and the double bag 4 is moved to the downstream side of the line 1 by using the double bag introducing pipe 34a. Introduce. Next, the bag introduction device 3
Thus, the normal bag 5 is formed using the bag introduction pipe 33a.
Is introduced toward the upstream side of the pipeline 1. Then, the first bag 41 is inflated using an air pump (not shown), and then the second bag 42 is inflated. Next, the bag 5 is inflated using an air pump.

As a result, the gas in the high-pressure pipe 1 is shut off, so that the gas flows through the bypass pipe 2 and is supplied to the downstream side. Further, since the gas pressure in the high-pressure pipe is high, the gas cannot be completely sealed by the first bag 41, and may flow into the space between the first bag and the second bag 42 beyond the first bag 41. is there. However, these overgases are discharged out of the pipeline by the suction hose 45.

Next, the other end of the suction hose 45 is connected to the lower part of the deodorizing device 6. The deodorizing device 6 has a cylindrical main body filled with a deodorizing material (adsorbent) such as activated carbon. The upper part of the deodorizing device communicates with the exhaust pipe 7, and the exhaust pipe 7 is equipped with a blower 8. Thus, when the blower 8 is driven, the inside of the deodorizing device 6 is made negative pressure by the negative pressure effect, and as a result, the gas in the suction hose 45 is discharged. Here, since the gas flowing through the suction hose 45 passes through the deodorizing device 6, TBM, DMS, TH
The odorant such as T is removed and discharged, and there is no complaint from the residents near the construction site.

[0022]

As described above, according to the first aspect of the present invention, the second bag composed of the first bag and the second bag.
An articulated bag is introduced into the line and the bag is inflated to shut off gas. And if the gas passes over the first bag,
Even when the gas flows into the space between the bag and the second bag, the overgas is discharged out of the pipeline. Therefore, gas does not flow into the repair work area, and work safety is ensured.

According to the second aspect of the present invention, since the airbag introduced into the pipe is of a double type consisting of the first bag and the second bag, the efficiency of shutting off gas can be increased. In addition, since the first bag and the second bag inflate and contract in independent air passages, even if one of them is damaged, it does not affect the other. Further, if the gas passes over the first bag and the first bag and the second bag
Even when the gas flows into the space between the bag and the bag, the overgas can be discharged out of the pipeline through the gas discharge passage.

According to the third aspect of the present invention, since the gas discharged from the discharge passage is discharged through the deodorizing device, the odorant such as TBM, DMS, and THT is removed and discharged. become. Therefore, there is no complaint from the residents around the construction site. Further, since the blower is connected to the deodorizing device, the gas can be forcibly discharged by the negative pressure effect.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a gas shutoff method according to an embodiment of the present invention.

FIG. 2 is an explanatory view of a bag introducing device.

FIG. 3 is an explanatory view of a double bag.

FIG. 4 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-pressure pipe 2 Bypass pipe 3 Bag introduction device 31 Pedestal 32 Shutter device 33 Bag introduction pipe hole 33a Bag introduction pipe 34 Double bag introduction pipe hole 34a Double bag introduction pipe 4 Double bag 41 First bag 42 Second bag 43 First air hose 44 Second air hose 45 Suction hose 5 Bag 6 Deodorizing device 7 Exhaust pipe 8 Blower

[Procedure amendment]

[Submission date] May 31, 1999 (1999.5.3
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] Gas shut-off method using a bag

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shut-off method and a gas shut-off device for shutting off gas flowing through a high-pressure pipe using a bag.

[0002]

2. Description of the Related Art Conventionally, as an example of means for repairing a gas pipeline laid underground, a construction method as shown in FIG. 4 is performed. First, a work pit is formed by excavating the area around a repair target location where a leak or the like has occurred. Next, a communication hole B for introducing the airbag A into the pipeline L is opened on the upstream side and the downstream side of the repair target location X, and the airbag A is contracted from the communication hole B in the pipeline. After the introduction is completed, the airbag A is inflated in the pipeline to cut off the gas flow. A communication hole D for forming a bypass pipe C is formed outside the position of the airbag A,
After the communication hole D is connected by the bypass pipe C and the supply of gas is secured, repair work is performed.

[0003]

When the above-mentioned repair method is applied to a high-pressure pipe, the gas pressure is so high that the bag cannot be completely sealed in some cases. For this reason, the gas that has passed through the bag (overgas) flows into the repair area, and the operation becomes very dangerous. Furthermore, if the gas is heavy, the gas will settle in the work pit, giving the worker an additional danger.

The present invention has been proposed in order to cope with such a situation. When repairing an existing pipeline, particularly a high-pressure pipeline, a gas shut-off using a bag that does not allow gas to flow into a work area. It is an object to provide a construction method and a bag device.

[0005]

In order to achieve the above-mentioned object, according to the present invention, there is provided a shut-off method comprising the steps of, when repairing an existing pipeline, a bag which can be inflated and contracted upstream of a portion of the pipeline to be repaired. In the gas shut-off method using a bag that inflates the bag to cut off the gas flow, a small-diameter communication hole is provided at a required position upstream of the repair target point in the pipeline. The first bag and the second bag
The bag is introduced toward the upstream side of the pipe line to inflate the double bag, and thereafter the first bag is inflated.
Gas flowing into the space between the bag and the second bag,
The apparatus is characterized in that the activated carbon is connected to a deodorizing apparatus having an inner layer, and a blower is connected to the deodorizing apparatus so as to be forcibly discharged to the atmosphere.

[0006]

According to the first aspect of the present invention, a double bag composed of the first bag and the second bag is introduced into the pipeline, and the bag is inflated to shut off gas. Even if the gas flows into the space between the first bag and the second bag over the first bag, the overgas is discharged out of the pipeline. At this time, the discharged gas passes through the deodorizing device and is discharged, so that TBM, DMS, THT
The odorant is removed and discharged. Therefore, there is no complaint from the residents around the construction site.
Further, since the blower is connected to the deodorizing device, the gas can be forcibly discharged by the negative pressure effect. Therefore, gas does not flow into the repair work area, and work safety is ensured.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of the gas shut-off method of the present invention.
In the figure, reference numeral 1 denotes an existing high-pressure pipeline 1 to be repaired, in which the upstream and downstream sides of the repair location are shut off in order to repair a required portion of the high-pressure pipeline 1, and the bypass pipe 2 is moved upstream and downstream from the shut-off position. It communicates downstream and performs repair work.

First, the bag introducing device 3 is installed in the communication holes 11 on the upstream side and the downstream side of the repair point of the high-pressure pipe 1.
The communication hole 11 may be an existing opening from which a diffuser tube or the like is removed, or a newly opened opening. As shown in FIG. 2, the bag introducing device 3 includes a pedestal 31 installed on the high-pressure pipeline 1, a shutter device 32 provided on the pedestal 31, and a double bag introducing pipe 34.
a and a bag introduction pipe 33a.

The pedestal 31 is formed with a double bag introduction pipe hole 34 and a bag introduction pipe hole 33 which are respectively inclined and opened to face each other. In FIG. 2, the double bag introduction pipe 34 a opens toward the downstream side of the high pressure pipeline 1, and the bag introduction pipe hole 33 opens toward the upstream side of the high pressure pipeline 1. ing. Although not shown, the pedestal 31 installed on the upstream side of the high-pressure line 1 has a double bag introduction pipe 34 a opened toward the upstream side of the high-pressure line 1. The bag introduction pipe hole 33 is open toward the downstream side. By doing so, each bag can be smoothly introduced into the upstream side and the downstream side of the pipeline 1.

Next, the double bag 4 will be described in detail with reference to FIG. As shown in FIG.
Has a first bag 41 at the front stage and a second bag 42 at the rear stage.

A first air hose 43 having one end facing the inside of the first bag 21 and the other end communicating with an air pump is connected to the first bag 41 while maintaining airtightness.
Supply and suction of air from the air hose 43 causes the first bag 4
1 is configured to expand and contract. Similarly, the second bag 42 has one end facing the inside of the second bag 42 and the other end communicating with the air pump.
Are connected while maintaining airtightness, and the second air hose 4
The second bag 42 is configured to be inflated and contracted by the supply and suction of air from the fourth bag 4.

As described above, the double bag is connected to the first bag 4.
By comprising the first and second bags 42, it is possible to improve the cutoff of gas flow in the pipeline. In addition, since the first bag 41 and the second bag 42 are inflated and contracted by the independent air hoses 43 and 44, even if one of them is damaged, it does not affect the other. Further, the first air hose 4 is provided in the second air hose 44.
3, the first air hose 43 does not interfere with the bag in the pipeline, and the first bag 41 and the second bag 42 Properly adhere to the inner wall of the pipe.

Next, a gas shutoff method using the bag constructed as described above will be described in detail with reference to FIG. First, from the bag introducing device 3 installed on the upstream side of the high pressure line 1,
Open the shutter device 32 and introduce the double bag introduction pipe 3
The double bag 4 is introduced to the upstream side of the pipeline 1 using 4a. Next, the normal bag 5 is introduced toward the downstream side of the pipeline 1 by using the bag introduction pipe 33a from the bag introduction device 3 in the same manner. Then, the first bag 41 is inflated using an air pump (not shown), and then the second bag 42 is inflated. Next, the bag 5 is inflated using an air pump.

Similarly, the shutter device 32 is opened by the bag introducing device 3 installed downstream of the high-pressure line 1 and the double bag 4 is moved downstream of the line 1 by using the double bag introducing pipe 34a. Introduce. Next, the bag introduction device 3
Thus, the normal bag 5 is formed using the bag introduction pipe 33a.
Is introduced toward the downstream side of the pipeline 1. Then, the first bag 41 is inflated using an air pump (not shown), and then the second bag 42 is inflated. Next, the bag 5 is inflated using an air pump.

As a result, the gas in the high-pressure pipe 1 is shut off, so that the gas flows through the bypass pipe 2 and is supplied to the downstream side. Further, since the gas pressure in the high-pressure pipe is high, the gas cannot be completely sealed by the first bag 41, and may flow into the space between the first bag and the second bag 42 beyond the first bag 41. is there.

Next, the first bag 41 and the second bag 42
Is communicated with the lower part of the deodorizing device 6. This deodorizing device 6 includes a deodorizing material (adsorbent) such as activated carbon in a cylindrical main body.
Is filled. The upper part of the deodorizing device communicates with the exhaust pipe 7, and the exhaust pipe 7 is equipped with a blower 8. As a result, when the blower 8 is driven, the inside of the deodorizing device 6 is made negative pressure by the negative pressure effect, and as a result, the gas in the space between the first bag and the second bag 42 is discharged. Since the gas sucked in here passes through the deodorizing device 6, the odorant such as TBM, DMS, and THT is removed by the activated carbon and discharged, and no complaint is generated from the residents and the like around the construction site.

[0017]

As described above, according to the present invention,
A double bag composed of a first bag and a second bag is introduced into the pipeline, and the bag is inflated to shut off gas.
And if the gas goes over the first bag and the first bag and the second
Even when the gas flows into the space between the bag and the bag, the overgas is discharged out of the pipeline. At that time, the discharged gas passes through the deodorizing device and is discharged.
Odorants such as MS and THT are removed and discharged. Therefore, there is no complaint from the residents around the construction site. Further, since the blower is connected to the deodorizing device, the gas can be forcibly discharged by the negative pressure effect. Therefore, gas does not flow into the repair work area, and work safety is ensured.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a gas shutoff method according to an embodiment of the present invention.

FIG. 2 is an explanatory view of a bag introducing device.

FIG. 3 is an explanatory view of a double bag.

FIG. 4 is an explanatory diagram of a conventional example.

[Description of Signs] 1 High-pressure line 2 Bypass tube 3 Bag introduction device 31 Pedestal 32 Shutter device 33 Bag introduction pipe hole 33a Bag introduction pipe 34 Double bag introduction pipe hole 34a Double bag introduction pipe 4 Double bag 41 1st bag 42 2nd bag 43 1st air hose 44 2nd air hose 5 Bag 6 Deodorizing device 7 Exhaust pipe 8 Blower

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Change

[Correction contents]

FIG. 3

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akihito Mori 8-19-35 Fukuda, Yamato-shi, Kanagawa (72) Inventor Masutoshi Okawa 4-10-20 Minami Tsukushino, Machida-shi, Tokyo (72) Inventor Takashi Komine 2-32-28 Inokashira, Mitaka City, Tokyo (72) Inventor Masahito Yamaguchi 1-2-2 Minamidai, Seya-ku, Yokohama-shi, Kanagawa F-term (reference) 3H025 DA02 DB17 DD01

Claims (3)

[Claims] 1. When an existing pipeline is repaired, an inflatable and deflated bag is introduced upstream of a repair target portion of the pipeline,
In the gas shut-off method using a bag for inflating the bag to cut off gas flow, a small-diameter communication hole is provided at a required position in the pipe upstream of a repair target point. A double bag composed of a first bag and a second bag is introduced into the road toward the upstream side of the pipeline to inflate the double bag, and thereafter, the first bag and the second bag A gas that flows into a space between the gas discharge device and the outside of the pipeline. 2. The dual bag has a first bag at a front stage and a second bag at a rear stage, and has a first air bag having one end facing the first bag and the other end communicating with an air pump. A second air passage having one end facing the inside of the second bag and the other end communicating with the air pump so that each bag can be expanded and contracted independently; and a first bag and a second bag. A gas discharge passage having one end facing a space between the bag device and the bag device. 3. The space between the first bag and the second bag, wherein the other end of the gas discharge passage according to claim 2 communicates with a deodorizer having activated carbon as an inner layer, and a blower communicates with the deodorizer. 2. The gas shut-off method according to claim 1, wherein the gas remaining in the section is deodorized and forcibly discharged to the atmosphere.