WO2024252533A1 - Laying method and laying system - Google Patents

Abstract

A laying method according to the present disclosure comprises: a step in which, in a state in which a second pipeline is inserted from one end of a first pipeline and is exposed from the other end of the first pipeline, a fixing jig (15) is used to fix the second pipeline and seal the one end of the first pipeline and a fixing jig (16) is used to fix the second pipeline and seal the other end of the first pipeline; a step in which a filler that is inert relative to the first pipeline and the second pipeline is injected into the space between the first pipeline and the second pipeline from a third pipeline inserted into an injection port (152); and a step in which, after completion of the packing of the filler into the space between the first pipeline and the second pipeline, the third pipeline is withdrawn from the first pipeline and the injection port (152) is closed by means of a shutoff valve (153).

Description

Laying method and system

This disclosure relates to an installation method and system.

In order to utilize hydrogen energy to achieve carbon neutrality, hydrogen pipelines for transporting hydrogen are being installed (see Non-Patent Document 1). Conventionally, when hydrogen pipelines are installed underground, the pipelines are buried directly in the ground. By burying the pipelines directly in the ground, the load in the soil acts as a restraining force, suppressing deformation due to elongation of the buried pipelines.

On the other hand, inner pipes for hydrogen pipelines and the like may also be laid inside existing pipelines that are already buried underground, such as communication pipelines. In these cases, flexible pipes are used as the inner pipes to accommodate the unevenness and curves of the existing pipeline. When laying a flexible pipe inside an existing pipeline, the flexible pipe is fixed in place with metal fittings or the like to restrict its extension.

Initiatives for hydrogen pipeline supply in the city gas industry, Journal of the Institute of Electrical Installation Engineers of Japan (April 2016)

Depending on the size of the existing pipeline that will become the sheath, there may be no space inside the existing pipeline to install hardware to secure the flexible pipe, or it may be difficult to install the hardware. In such cases, the flexible pipe cannot be secured in place, and the stretching of the flexible pipe may lead to buckling or breakage of the flexible pipe inside the existing pipeline.

In addition, if a hydrogen pipeline is buried directly underground, even if hydrogen leaks due to damage to the pipeline, the leaked hydrogen will be dispersed into the soil. On the other hand, if a flexible pipe is laid inside an existing pipeline, and the flexible pipe is damaged due to buckling or corrosion, there is a risk that flammable hydrogen will leak and become trapped between the existing pipeline and the flexible pipe.

Therefore, there is a demand for technology that can suppress deformation such as stretching and bending of flexible pipes when laying them inside existing pipelines.

The purpose of this disclosure, made in consideration of the above problems, is to provide an installation method and installation system that can suppress deformation of the second pipeline installed inside the first pipeline.

In order to solve the above problem, the laying method according to the present disclosure is a laying method for laying a second pipeline inside a first pipeline buried underground, and includes the steps of: fixing the second pipeline and sealing one end of the first pipeline with a first fixing jig having an injection port and a shutoff valve capable of closing the injection port, while the second pipeline is inserted into one end of the first pipeline and exposed from the other end of the first pipeline, and fixing the second pipeline and sealing the other end of the first pipeline with a second fixing jig; injecting a filler that is inactive with respect to the first pipeline and the second pipeline from a third pipeline inserted into the injection port between the first pipeline and the second pipeline; and, after the filling of the filler between the first pipeline and the second pipeline is completed, pulling out the third pipeline from the first pipeline and closing the injection port with the shutoff valve.

In order to solve the above problem, the installation system according to the present disclosure is an installation system for laying a second pipeline inside a first pipeline buried underground, and includes a traction device that traction-exposes the second pipeline inserted from one end of the first pipeline from the other end of the first pipeline, an injection port, and a shutoff valve that can shut off and open the injection port, and fixes the second pipeline and seals one end of the first pipeline when the second pipeline is inserted from one end of the first pipeline. a first fixing jig for fixing the second pipeline in a state in which the second pipeline is exposed from the other end of the first pipeline and sealing the other end of the first pipeline; an injection device for injecting a filler that is inactive with respect to the first pipeline and the second pipeline from a third pipeline inserted into the injection port between the first pipeline and the second pipeline; and a winding device for pulling out the third pipeline from the first pipeline after the filling of the filler between the first pipeline and the second pipeline is completed.

The installation method and system disclosed herein can suppress deformation of the second pipeline installed inside the first pipeline.

FIG. 1 is a diagram illustrating a configuration example of an installation system according to an embodiment of the present disclosure. FIG. 2 is a front view of the fixing jig 15 shown in FIG. 2 is a diagram showing members constituting the fixing jig 15 shown in FIG. 1 before being connected together. FIG. 2 is a diagram showing a state in which the fixing jig 15 shown in FIG. 1 is fixed to one end of an existing pipeline. FIG. 2 is a front view of the fixing jig 16 shown in FIG. 2 is a diagram showing members constituting the fixing jig 16 shown in FIG. 1 before being connected together. 2 is a flowchart for explaining a laying method using the laying system shown in FIG. 1 .

The following describes an embodiment of the present disclosure with reference to the drawings.

FIG. 1 is a diagram showing an example of the configuration of an installation system 10 according to an embodiment of the present disclosure. The installation system 10 according to this embodiment is for installing an inner pipeline as a second pipeline inside an existing pipeline 1 as a first pipeline, such as a communication pipeline, buried underground. In the following, the inner pipeline is assumed to be a flexible pipe 2 having flexibility. The existing pipeline 1 is provided so as to connect underground structures 4 installed underground, such as manholes, handholes, or tunnels, for example, as shown in FIG. 1.

As shown in FIG. 1, the installation system 10 according to this embodiment includes a sending device 11, a towing device 12, a winding device 13, an injection device 14, and fixing devices 15 and 16. The sending device 11, the towing device 12, the winding device 13, and the injection device 14 are installed, for example, on the ground.

The delivery device 11 has the function of storing the flexible tube 2. The delivery device 11 can deliver the stored flexible tube 2 in accordance with the towing of the flexible tube 2 by the towing device 12 described below.

The towing device 12 is equipped with a towing jig 12a to which the flexible pipe 2 can be fixed, and can tow the flexible pipe 2 fixed to the towing jig 12a at a speed specified by an operator or the like. In this embodiment, as shown in FIG. 1, the towing device 12 tows the flexible pipe 2 inserted from one end 1a of the existing pipeline 1 from the other end 1b of the existing pipeline 1, and exposes it from the other end 1b of the existing pipeline 1. By fixing the injection pipe 3 (described later) near the tip of the flexible pipe 2, the towing device 12 can tow the injection pipe 3 together with the flexible pipe 2.

The winding device 13 has the function of storing the injection tube 3 as the third pipeline. The winding device 13 can feed out the stored injection tube 3 in accordance with the towing device 12 pulling the flexible pipe 2 to which the injection tube 3 is fixed. The winding device 13 can also wind up the injection tube 3 pulled out by the towing device 12 at a speed specified by an operator or the like. The winding device 13 can pull out the injection tube 3 from the existing pipeline 1 after the injection device 14, described below, has completed filling the space between the existing pipeline 1 and the flexible pipe 2 with the filling material.

The injection device 14 has a function of containing a filler that is inactive to the existing pipeline 1 and the flexible pipe 2. The filler is not particularly limited as long as it is inactive to the existing pipeline 1 and the flexible pipe 2 (i.e., it does not cause corrosion of the existing pipeline 1 and the flexible pipe 2) and can fill the gap between the existing pipeline 1 and the flexible pipe 2. The filler is, for example, dry sand. In the following description, the filler is dry sand. The injection device 14 injects the dry sand, which is the filler to be contained, from the injection pipe 3 between the existing pipeline 1 and the flexible pipe 2. The injection device 14 can discharge the contained dry sand at a speed specified by an operator or the like. The injection device 14 may inject at least one of an oxygen scavenger and a desiccant together with the dry sand. When the existing pipeline 1 is a metallic pipeline, the progress of corrosion due to various oxidation reactions caused by contact with the atmosphere, water, or other metals in the existing pipeline 1 can be suppressed by injecting at least one of an oxygen scavenger and a desiccant together with the dry sand.

The fixing jig 15, which serves as the first fixing jig, can fix the flexible pipe 2 in a state in which the flexible pipe 2 is inserted from one end 1a of the existing pipeline 1. As shown in FIG. 1, the fixing jig 15 is fixed to the frame of the underground structure 4 at one end 1a of the existing pipeline 1, and seals one end 1a of the existing pipeline 1.

Figure 2 is a front view of the fixing jig 15.

As shown in FIG. 2, the fixture 15 has a passage port 151, an injection port 152, and a shutoff valve 153.

The passage port 151, which serves as the first passage port, allows the flexible pipe 2 to pass through and can fix the flexible pipe 2 that has passed through the passage port 151. As shown in FIG. 2, a half fixing plate 151a is provided on the inner periphery of the passage port 151. The position of the fixing plate 151a can be adjusted in the radial direction of the passage port 151 by the adjustment screw 151b. The flexible pipe 2 that has passed through the passage port 151 can be fixed by adjusting the position of the fixing plate 151a by the adjustment screw 151b to match the thickness of the flexible pipe 2.

The injection port 152 allows the injection tube 3 to pass through. The shutoff valve 153 can close and open the injection port 152.

2, the fixing jig 15 includes a first member 154, a second member 155 connectable to the first member 154, and a third member 156 connectable to the second member 155. As shown in FIG. 3, the first member 154, the second member 155, and the third member 156 are provided separately, and the fixing jig 15 is formed by connecting these members. Note that the fixing plate 151a, the adjustment screw 151b, and the shutoff valve 153 are omitted from FIG. 3.

The first member 154 is a rectangular member in a plan view, and has a semicircular recess 154a on one side.

The second member 155 is a rectangular member in a plan view, with a semicircular recess 155a on one side and a semicircular recess 155b on the other side opposite the first side. The first member 154 and the second member 155 are connected, for example, by a screw 155c, so that the side on which the recess 154a is provided is in contact with the side on which the recess 155a is provided. The passage opening 151 is formed by connecting the first member 154 and the second member 155.

The third member 156 is a rectangular member in a plan view, and has a semicircular recess 156a on one side. The second member 155 and the third member 156 are connected, for example, by a screw 156b, so that the side on which the recess 155b is provided is in contact with the side on which the recess 156a is provided. The injection port 152 is formed by connecting the second member 155 and the third member 156.

Referring again to FIG. 2, the fixing jig 15 has a fixing portion 157 for fixing to the frame of the underground structure 4 with an anchor or a screw. FIG. 4 shows the state in which the fixing jig 15 is fixed to the frame of the underground structure 4.

As shown in FIG. 4, the fixing jig 15 has an insertion portion 158 that is inserted into the existing pipeline 1 from one end 1a of the existing pipeline 1. The outer diameter of the insertion portion 158 is approximately equal to the inner diameter of the existing pipeline 1. With the insertion portion 158 inserted into the existing pipeline 1, the fixing jig 15 is fixed to the structure of the underground structure 4 from the inside of the structure (side surface) of the underground structure 4. In this way, the fixing jig 15 can seal one end 1a of the existing pipeline 1. Airtightness can be further improved by wrapping security tape 159 or the like around the passage opening 151 and the flexible pipe 2 for protection.

As described with reference to Figures 2 to 4, the fixing jig 15 is formed by connecting the first member 154, the second member 155, and the third member 156, so that after the flexible pipe 2 and the injection pipe 3 are inserted into the existing pipeline 1, the fixing jig 15 can seal one end 1a of the existing pipeline 1 with the flexible pipe 2 passing through the passage port 151 and the injection pipe 3 passing through the injection port 152.

Referring again to FIG. 1, the fixing jig 16 as the second fixing jig can fix the flexible pipe 2 in a state where the flexible pipe 2 is exposed from the other end 1b of the existing pipeline 1. As shown in FIG. 1, the fixing jig 16 is fixed to the body of the underground structure 4 at the other end 1b of the existing pipeline 1, and seals the other end 1b of the existing pipeline 1.

Figure 5 is a front view of the fixing jig 16.

As shown in FIG. 5, the fixing jig 16 has a passage opening 161.

The passage opening 161 allows the flexible pipe 2 to pass through and can also fix the flexible pipe 2 that has passed through the passage opening 161. As shown in FIG. 5, a half fixing plate 161a is provided on the inner periphery of the passage opening 161. The position of the fixing plate 161a can be adjusted in the radial direction of the passage opening 161 by the adjustment screw 161b. The flexible pipe 2 that has passed through the passage opening 161 can be fixed by adjusting the position of the fixing plate 161a by the adjustment screw 161b to match the thickness of the flexible pipe 2.

As shown in FIG. 5, the fixing jig 16 includes a fourth member 164 and a fifth member 165 that can be connected to the fourth member 164. As shown in FIG. 6, the fourth member 164 and the fifth member 165 are provided separately, and are connected to form the fixing jig 16.

The fourth member 164 is a rectangular member in a plan view, and has a semicircular recess 164a on one side.

The fifth member 165 is a rectangular member in a plan view, and has a semicircular recess 165a on one side. The fourth member 164 and the fifth member 165 are connected, for example, by a screw 165c, so that the side on which the recess 164a is provided and the side on which the recess 165a is provided are in contact with each other. The passage opening 161 is formed by connecting the fourth member 164 and the fifth member 165.

Referring again to FIG. 5, the fixing jig 16 has a fixing portion 167 for fixing to the frame of the underground structure 4 with an anchor or a screw. The method of fixing to the underground structure 4 is the same as for the fixing jig 15, so a description thereof will be omitted.

Next, the installation method using the installation system 10 according to this embodiment will be described with reference to the flowchart shown in FIG. 7.

The flexible pipe 2 and the injection pipe 3 inserted from one end 1a of the existing pipeline 1 are pulled by the towing device 12, so that the flexible pipe 2 and the injection pipe 3 are laid inside the existing pipeline 1 (step S11).

Specifically, a towing jig 12a is attached to the tip of a flexible pipe 2 inserted from one end 1a of the existing pipeline 1. An injection pipe 3 is tied to the flexible pipe 2 near its tip. With the injection pipe 3 tied to the flexible pipe 2, the flexible pipe 2 is towed by the towing device 12, causing the flexible pipe 2 to be sent out from the sending device 11 and the injection pipe 3 to be sent out from the winding device 13, and the flexible pipe 2 and the injection pipe 3 to be pulled into the existing pipeline 1.

When the flexible pipe 2 and the injection pipe 3 are exposed from the other end 1b of the existing pipeline 1, the towing by the towing device 12 is stopped. With the flexible pipe 2 and the injection pipe 3 exposed from the other end 1b of the existing pipeline 1, the binding between the flexible pipe 2 and the injection pipe 3 is released. After the binding between the flexible pipe 2 and the injection pipe 3 is released, the winding device 13 winds up the injection pipe 3 so that the tip of the injection pipe 3 is located inside the existing pipeline 1. In this way, the flexible pipe 2 is exposed from the other end 1b of the existing pipeline 1, and the injection pipe 3 can be laid in a state where it is placed in the existing pipeline 1. It is preferable that the injection pipe 3 is positioned so that the tip of the injection pipe 3 is located near the other end 1b of the existing pipeline 1.

Next, fixing jigs 15, 16 are attached to the existing pipeline 1 (step S12). Specifically, the fixing jig 15 fixes the flexible pipe 2 and seals one end 1a of the existing pipeline 1. The fixing jig 16 fixes the flexible pipe 2 and seals the other end 1b of the existing pipeline 1.

As described above, the fixing jig 15 is attached to the existing pipeline 1 with the flexible pipe 2 passing through the passage port 151 and the injection pipe 3 passing through the injection port 152, and seals one end 1a of the existing pipeline 1. The fixing jig 15 can be attached to the existing pipeline 1 in this state by sequentially connecting the first member 154, the second member 155, and the third member 156.

For example, by connecting the first member 154 and the second member 155 with the flexible tube 2 placed in the recess 154a of the first member 154 and the recess 155a of the second member 155, the flexible tube 2 can be placed in a state of passing through the passage port 151. Also, by connecting the second member 155 and the third member 156 with the injection tube 3 placed in the recess 155b of the second member 155 and the recess 156a of the third member 156, the injection tube 3 can be placed in a state of passing through the injection port 152.

Then, by attaching the fixing jig 15 to one end 1a of the existing pipeline 1 and adjusting the position of the fixing plate 151a with the adjustment screw 151b, the one end 1a of the existing pipeline 1 can be sealed with the flexible pipe 2 fixed by the fixing jig 15.

As described above, the fixing jig 16 is attached to the existing pipeline 1 with the flexible pipe 2 passing through the passage opening 161, and seals the other end 1b of the existing pipeline 1. The fixing jig 16 can be attached to the existing pipeline 1 in this state by connecting the fourth member 164 and the fifth member 165.

For example, by connecting the fourth member 164 and the fifth member 165 with the flexible tube 2 placed in the recess 164a of the fourth member 164 and the recess 165a of the fifth member 165, the flexible tube 2 can be placed in a state of passing through the passage opening 161.

Then, by attaching the fixing jig 16 to the other end 1b of the existing pipeline 1, the other end 1b of the existing pipeline 1 can be sealed while the flexible pipe 2 is fixed by the fixing jig 16.

Next, the injection device 14 starts injecting dry sand from the injection pipe 3 inserted into the injection port 152 into the space between the existing pipeline 1 and the flexible pipe 2 (step S13).

When the injection of dry sand begins, the winding device 13 starts winding the injection pipe 3 at a constant speed (step S14). By winding the injection pipe 3 with dry sand injected from the injection pipe 3, the dry sand is injected sequentially toward one end 1a of the existing pipeline 1. The speed at which the injection pipe 3 is wound is set so that the space between the existing pipeline 1 and the flexible pipe 2 (between the inner diameter of the existing pipeline 1 and the outer diameter of the flexible pipe 2) is sufficiently filled with dry sand (at least to the extent that the flexible pipe 2 is buried in dry sand).

When the injection pipe 3 is pulled out from the existing pipeline 1, the injection device 14 stops injecting the dry sand (step S15).

After the injection of the dry sand is stopped, the injection port 152 is closed by the shutoff valve 153 of the fixing jig 15 (step S16). This seals the existing pipeline 1 with the dry sand filled between the existing pipeline 1 and the flexible pipe 2.

The laying method using the laying system 10 according to this embodiment thus includes the steps of: fixing the flexible pipe 2 with the fixing jig 15 and sealing one end 1a of the existing pipeline 1 while the flexible pipe 2 is inserted into one end 1a and exposed from the other end 1b of the existing pipeline 1; fixing the flexible pipe 2 with the fixing jig 15 and sealing the other end 1b of the existing pipeline with the fixing jig 16 (steps S11 and S12); injecting a filler (e.g., dry sand) that is inactive to the existing pipeline 1 and the flexible pipe 2 between the existing pipeline 1 and the flexible pipe 2 from the injection pipe 3 inserted into the injection port 152 (steps S13 and S14); and, after the filling of the filler between the existing pipeline and the flexible pipe 2 is completed, pulling out the injection pipe 3 from the existing pipeline 1 and closing the injection port 152 with the shutoff valve 153 (steps S15 and S16).

By filling the gap between the first pipeline (existing pipeline 1) and the second pipeline (flexible pipe 2), the second pipeline is restrained by the reaction force of the filled pipeline, and deformation such as extension and bending of the second pipeline inside the first pipeline can be suppressed. Therefore, deformation of the second pipeline laid inside the first pipeline can be suppressed. In addition, in this embodiment, the existing pipeline 1 already buried underground is used to lay the second pipeline, which reduces the scope of construction such as cutting, making it possible to lay an economical hydrogen pipeline. In addition, since the filler is filled between the first pipeline and the second pipeline, even if gas (e.g., hydrogen) leaks from the second pipeline, the space in which the leaked gas stagnates between the first pipeline and the second pipeline is reduced, so that the stagnation of the leaked gas can be suppressed.

The following notes are further provided with respect to the above embodiment.

[Additional Note 1]
A method for laying a second pipeline inside a first pipeline buried underground, comprising the steps of:
a first fixing jig having an injection port and a shutoff valve capable of closing the injection port, the second pipe is fixed and the first pipe is sealed at one end thereof, and a second fixing jig is used to fix the second pipe and seal the other end thereof, with the second pipe being inserted into the first pipe and exposed from the other end thereof;
injecting a filler that is inactive with respect to the first pipeline and the second pipeline from a third pipeline inserted into the injection port between the first pipeline and the second pipeline;
the third pipeline is pulled out from the first pipeline, and the injection port is closed by the shutoff valve after the filling of the filler between the first pipeline and the second pipeline is completed.

[Additional Note 2]
In the laying method described in appended paragraph 1,
The method of laying, wherein the filler is dry sand.

[Additional Note 3]
In the laying method according to claim 1 or 2,
The installation method further comprises injecting at least one of an oxygen scavenger and a desiccant between the first pipeline and the second pipeline.

[Additional Note 4]
The method according to any one of claims 1 to 3,
the first fixing jig has a first member, a second member connectable to the first member, and a third member connectable to the second member, the first member and the second member being connected to each other to form a first passage port through which the first pipeline passes, and the second member and the third member being connected to each other to form the injection port,
the second fixing jig has a fourth member and a fifth member connectable to the fourth member, and a second passage port through which the first pipeline passes is formed by connecting the fourth member and the fifth member;
inserting the second pipeline and the third pipeline from one end of the first pipeline, exposing the second pipeline from the other end of the first pipeline, and arranging the third pipeline inside the first pipeline;
connecting the first member and the second member with the second pipeline passing through the first passage port, connecting the second member and the third member with the third pipeline passing through the injection port, and connecting the fourth member and the fifth member with the second pipeline passing through the second passage port.

[Additional Note 5]
A system for laying a second pipeline inside a first pipeline buried underground, comprising:
a pulling device that pulls the second pipeline inserted from one end of the first pipeline from the other end side of the first pipeline to expose the second pipeline from the other end of the first pipeline;
a first fixing jig having an injection port and a shutoff valve capable of shutting off and opening the injection port, the first fixing jig fixing the second pipe and sealing the one end of the first pipe in a state in which the second pipe is inserted into the one end of the first pipe;
a second fixing jig that fixes the second pipeline and seals the other end of the first pipeline in a state in which the second pipeline is exposed from the other end of the first pipeline;
an injection device that injects a filler that is inactive with respect to the first pipeline and the second pipeline from a third pipeline inserted into the injection port between the first pipeline and the second pipeline;
and a winding device that pulls out the third pipeline from the first pipeline after the filling of the filler between the first pipeline and the second pipeline is completed.

The above-mentioned embodiments have been described as representative examples, but it will be apparent to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present disclosure. Therefore, the present invention should not be interpreted as being limited by the above-mentioned embodiments, and various modifications or changes are possible without departing from the scope of the claims. For example, it is possible to combine multiple configuration blocks shown in the configuration diagram of the embodiment into one, or to divide one configuration block.

1. Existing pipeline (First pipeline)
2 Inner pipe (second pipe)
3 Injection pipe 4 Underground structure 10 Laying system 11 Delivery device 12 Traction device 12a Traction jig 13 Winding device 14 Supply device 15 Fixing jig (first fixing jig)
16 Fixture (second fixture)
151 Passing port (first passing port)
151a, 161a Fixing plate 151b, 161b Adjusting screw 152 Inlet 153 Shutoff valve 154 First member 154a, 155a, 155b, 156a, 164a, 165a Recess 155 Second member 155c, 156b, 165c Screw 156 Third member 157, 167 Fixing portion 158 Insertion portion 161 Passing port (second passing port)
164 Fourth member 165 Fifth member

Claims (5)

A method for laying a second pipeline inside a first pipeline buried underground, comprising the steps of:
a step of fixing the second conduit and sealing the one end of the first conduit with a first fixing jig having an injection port and a shutoff valve capable of closing the injection port, in a state in which the second conduit is inserted from one end of the first conduit and exposed from the other end of the first conduit, and fixing the second conduit and sealing the other end of the first conduit with a second fixing jig;
injecting a filler that is inert to the first and second pipelines from a third pipeline inserted into the injection port between the first and second pipelines;
After completion of filling the space between the first pipeline and the second pipeline with the filler, the third pipeline is pulled out from the first pipeline and the injection port is closed by the shutoff valve. The method of claim 1,
The method of laying, wherein the filler is dry sand. The method of claim 1,
The installation method further comprises injecting at least one of an oxygen scavenger and a desiccant between the first pipeline and the second pipeline. The method of claim 1,
the first fixing jig has a first member, a second member connectable to the first member, and a third member connectable to the second member, the first member and the second member being connected to each other to form a first passage port through which the first pipeline passes, and the second member and the third member being connected to each other to form the injection port,
the second fixing jig has a fourth member and a fifth member connectable to the fourth member, and a second passage port through which the first pipeline passes is formed by connecting the fourth member and the fifth member;
inserting the second pipeline and the third pipeline from one end of the first pipeline, exposing the second pipeline from the other end of the first pipeline, and arranging the third pipeline inside the first pipeline;
connecting the first member and the second member with the second pipeline passing through the first passage port, connecting the second member and the third member with the third pipeline passing through the injection port, and connecting the fourth member and the fifth member with the second pipeline passing through the second passage port. A system for laying a second pipeline inside a first pipeline buried underground, comprising:
a pulling device that pulls the second pipeline inserted from one end of the first pipeline from the other end side of the first pipeline to expose the second pipeline from the other end of the first pipeline;
a first fixing jig having an injection port and a shutoff valve capable of shutting off and opening the injection port, the first fixing jig fixing the second pipe and sealing the one end of the first pipe in a state in which the second pipe is inserted into the one end of the first pipe;
a second fixing jig that fixes the second pipeline and seals the other end of the first pipeline in a state in which the second pipeline is exposed from the other end of the first pipeline;
an injection device that injects a filler that is inactive with respect to the first pipeline and the second pipeline from a third pipeline inserted into the injection port between the first pipeline and the second pipeline;
and a winding device that pulls out the third pipeline from the first pipeline after the filling of the filler between the first pipeline and the second pipeline is completed.

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