JP2002031289A - Pipe laying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe laying method performing boring works without moving an adapter used for boring according to the laying direction of an existing pipe and surely prevent the leakage in various works such as the boring works. SOLUTION: This method is to bore a branch opening having approximately same diameter as the existing pipe in a part of the laying section of the existing pipe and connect a bypass pipe or a newly establish pipe to the bored part. The boring adapter 1 capable of fitting a boring device for boring a plurality of branch openings along the circumferential direction and laying direction of the existing pipe is fitted without being moved at the connection position of the pipe except for the existing pipe and a shutter device 3 provided in the boring adapter 1 is also selectively opened/closed. This method is characterized in that the leakage is thus prevented with the boring adapter 1 stationarily installed thereon and the branch opening having same bore with the existing pipe is formed so that works using various work devices can be performed via the branch openings.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe laying method, and more particularly, to a so-called turning method for connecting a bypass pipe or a new pipe to an existing pipe.

[0002]

2. Description of the Related Art When a bypass pipe or a new pipe is provided in the middle of an existing pipe through which a fluid such as gas flows, an opening for branching and taking out is formed in the existing pipe to which the pipe is connected. Conventionally, an opening for branch take-out (hereinafter, referred to as
When the branch opening is formed, for example, in the case where the branch opening is formed on the upper peripheral surface of the existing pipeline, a split joint is mounted at a position where the branch opening is formed, and a drilling machine is provided at the split joint. An adapter is installed to allow the drill to be set on the adapter. When the drilling machine is set, the hole saw is advanced toward the branch opening to perform the drilling.

[0003]

As a type of taking out a branch, there is a branch having the same area in addition to a branch having a smaller diameter than a pipe having an existing diameter. The latter branch having the same area is of a type in which a branch opening having the same area as the diameter of the existing pipeline is perforated in order to equalize the flow rate between the existing pipeline and the branch side. In the case of branching in the same area, the drilling method differs depending on the material of the existing pipeline. When a polyethylene pipe or the like is used, it is possible to use a drilling machine having a single hole saw capable of forming a branch opening having the same diameter as the existing pipeline. This is because, in the case of a polyethylene pipe, the branch joint and the existing pipeline can be fused together, and it is sufficient if there is a margin for fusion. However, when the existing pipeline is a metal pipe such as a cast iron pipe, a drilling machine provided with a hole saw having the above-described diameter cannot be used by regulation. For this reason, in order to provide a branch opening having an area corresponding to the diameter of the existing pipeline, it is necessary to form a plurality of openings in the laying direction of the existing pipeline using a drilling machine having a hole saw having a size smaller than the diameter. ,
Or, in order to pierce with a hole saw of the same diameter, by welding the joint surface between the joints attached to the branch opening forming position and the pipe axial end face of the joint and the peripheral surface of the existing pipeline, the joints and the joint are formed. The existing pipes are integrated with each other to maintain the strength of the pipe and prevent leakage from the inside. In the latter method,
In addition to the need to move the drilling adapter equipped with the drilling machine in the direction in which the existing pipeline is laid in accordance with the drilling position, it is also necessary to perform an operation for matching the drilling position in the laying direction. For this reason, the number of man-hours including attachment and detachment of the perforated adapter is increased. Further, since it is necessary to weld the joint, a non-destructive inspection is also required in addition to the welding work, so that the number of working steps cannot be denied, which may lead to an increase in processing cost. When a bypass pipe or a new pipe is formed by using a branch pipe, the flow may be performed without stopping the flow of fluid such as gas flowing in the existing pipe. For this reason, when connecting branch pipes, the gas flow is usually continued until both ends of the existing pipes are cut off, including drilling work and sections where bypass pipes and new pipes are laid. It is important that leakage does not occur. However, as mentioned above,
Even when the joint provided for mounting the drilling machine and the existing pipeline are integrated by welding and the interior is sealed, strict precautions must be taken when performing replacement work such as removing and mounting the drilling adapter. If the perforated adapter is released from the peripheral surface of the existing pipeline even if the cost is paid, it becomes difficult to prevent the gas from leaking from the released portion.

SUMMARY OF THE INVENTION [0004] In view of the above-mentioned problems in the conventional formation of a branch opening, an object of the present invention is to make it possible to perform a drilling operation without moving an adapter used for drilling in the direction in which an existing pipeline is laid. Another object of the present invention is to provide a pipe laying method capable of reliably preventing leakage during various operations.

[0005]

In order to achieve this object, according to the present invention, a part of a section in which an existing pipeline is laid is formed by piercing a branch opening having substantially the same diameter as the existing pipeline. A method for connecting a bypass pipe or a new pipe to a perforated portion, wherein a closed space is formed between the pipe and an outer peripheral surface of the existing pipe when the pipe is attached to each end of the existing pipe. A perforated adapter including a branch outlet at a position facing the existing pipeline in the circumferential direction in the closed space, and a shutter device for controlling a communication state between the branch outlet and the closed space. Used, a pipe other than the existing pipe is connected to one of the branch outlets, and a hole is taken out of the branch outlet on the side opposite to the branch outlet on which the pipe other than the existing pipe is connected. Equipment and grinding used after drilling Mounting in the working order, at least the drilling device is mounted in a state of being displaceably supported in the circumferential direction and the laying direction of the existing pipeline to form a plurality of branch openings along the circumferential direction and the laying direction, after grinding, A blocking device for sealing both ends of the blocking section in the existing pipeline is inserted into the existing pipeline from the branch outlet on the side where the grinding device is attached, and each end of the blocking section in the existing pipeline is divided. When the shut-off device is removed from the branch outlet at the time of being sealed, after the shielding of the branch outlet is completed, the shutter device on the branch outlet side to which the pipeline other than the existing pipeline is connected is opened. It is characterized in that it is opened and a fluid from an existing pipeline is introduced into the pipeline.

According to a second aspect of the present invention, there is provided the pipe laying method according to the first aspect, wherein, among the shutter devices on the branch take-out port side to which pipes other than the existing pipe are connected,
It is characterized in that the shutter device located on the upstream side in the flow direction of the fluid flowing in the existing pipeline is opened after grinding, so that the purging fluid flows into the pipeline other than the existing pipeline.

According to a third aspect of the present invention, in the pipe laying method according to the first aspect, the shut-off device includes an inflatable bag and resists the pressure of the fluid flowing through the existing pipeline. And a support structure that stands upright in a direction perpendicular to the flow direction of the fluid and maintains a state of being in close contact with the inner surface of the existing pipeline.

According to a fourth aspect of the present invention, in the pipe laying method according to the third aspect, the blocking device can be left or taken out of the existing pipeline.

[0009]

According to the first aspect of the present invention, a plurality of branch openings can be formed along the circumferential direction and the laying direction of the existing pipeline because the drilling device attached to the branch outlet provided in the drilling adapter is used. Thus, the drilling operation can be performed without moving the drilling adapter with respect to the existing pipeline. Moreover, the perforated branch opening,
Since it will be the introduction part of the grinding device and the blocking device,
There is no need to provide an opening for such a working device. Furthermore, since the shutter device can be opened and closed corresponding to each branch outlet, leakage at the time of replacement of various working devices can be minimized.

According to the second aspect of the present invention, by opening and closing the shutter device provided in the perforated adapter, the purging fluid can be flown into the pipes other than the existing pipes. Separately, there is no need to configure a conduit for guiding a purge fluid to a conduit other than the existing conduit.

According to the third aspect of the present invention, the shutoff device introduced into the existing pipeline from the perforated branch opening includes a bag that is in close contact with the inner surface of the existing pipeline, and the bag is connected to the existing pipe against the pressure of the fluid. Since the support structure that can maintain the upright state in the road is provided, the support strength of the bag that is in close contact with the inner surface of the existing pipeline can be increased.

According to the fourth aspect of the present invention, the shutoff device can select either to be left or taken out of the existing pipeline, and when it is left, it can function as a sector valve in the existing pipeline. There is no need to prepare a sector valve again. Thereby, cost can be reduced.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a state in which a branch portion forming adapter corresponding to a perforated adapter used in a pipe laying method according to an embodiment of the present invention is mounted on an existing pipeline. In the figure, the branch portion forming adapter 1 has a size that can cover the entire circumferential area of the existing pipeline 2 and can form a closed space S with the outer peripheral surface of the existing pipeline 2 in a covered state. The upper frame 1A and the lower frame 1A 'having a symmetrical structure which is divided into two parts in the circumferential direction with a diameter passing through the center of the cross section of the existing pipeline 2 as a boundary. In the upper frame 1A and the lower frame 1A 'constituting the branch portion forming adapter 1, the flanges 1A1 and 1A1' provided on the dividing surface are joined together by fastening or the like (for convenience, the fastening points are indicated by dashed lines in FIG. 1). )
Then, they are integrated and mounted on the existing pipeline 2.
As a result, since the branch portion forming adapter 1 is assembled only by fastening the upper and lower frames 1A and 1A ', unlike the welding work, the man-hour is reduced and a special process such as a non-destructive inspection is not required. Can be.

As shown in FIG. 2, the branch portion forming adapter 1 mounted on the existing pipeline 2 includes an annular projection 2A previously formed on the existing pipeline 2 and an upper frame 1A and a lower frame 1A.
By fitting into the recess formed in A ′, the existing pipeline 2 is mounted in a state where movement in the laying direction is prevented.

The upper frame 1A and the lower frame 1A 'of the adapter 1 for forming a branch portion are integrally provided with branch outlets 1A2 and 1A2' having an opening communicating with the closed space S. On the closed space S side with respect to the openings of the outlets 1A2, 1A2 ', shutter devices 3, 3' capable of opening and closing the openings are provided. The shutter devices 3 and 3 'include a sealing box member 3A, 3A' attached to the inner surface of the upper frame 1A and the lower frame 1A ', and a sealing box member 3A.
Sliding rods 3B, 3B 'inserted through the wall of 3A';
Shutter bodies 3C, 3C 'attached to one axial end of the sliding rods 3B, 3B'. The sealing box members 3A, 3A 'are connected to the branch outlets 1A2, 1A.
A member that shields the opening 2 ′ and the closed space S, and a communication opening 3A1 that communicates the closed space S with the branch outlets 1A2, 1A2 ′ at a position facing the branch outlets 1A2, 1A2 ′. 3A1 'is formed. The sliding rods 3B, 3B ′ are such that one end in the axial direction is located inside the sealing box members 3A, 3A ′ with the walls of the sealing box members 3A, 3A ′ as boundaries, and the other end in the axial direction is the upper frame 1A, It penetrates the wall of the lower frame 1A 'and projects to the outside.

The shutter bodies 3C, 3C 'are provided at one axial end of sliding rods 3B, 3B' located in the sealing box members 3A, 3A '. That is, the shutter bodies 3C and 3C 'open and close the communication openings 3A1 and 3A1' formed on the bottom surfaces of the sealing box members 3A and 3A 'to open the closed space S and the branch outlets 1A2 and 1A2'. Is a member for controlling the communication state with the sliding rod 3
B, 3B 'is fastened at one axial end,
It can move in the axial direction of the sliding rods 3B, 3B 'according to the rotation direction of the sliding rods 3B, 3B', and opens and closes the communication openings 3A1, 3A1 'according to the moving direction. The communication state between S and the branch outlets 1A2, 1A2 'can be switched.

As will be described later, the shutter body 3C is sized to cover the branch opening on the existing pipeline 2 exposed from the communication openings 3A1 and 3A1 '. The branch openings exposed from the communication openings 3A1 and 3A1 'are configured such that those having a diameter smaller than the diameter of the existing pipeline 2 are continuously formed in the circumferential direction and the laying direction, and the shutter bodies 3C and 3C'. Covers a plurality of branch openings formed in the existing pipeline 2 to form a closed space S and a branch outlet 1A2,
Communication with 1A2 'can be cut off.

In order to form a branch opening P1 on the peripheral surface of the existing pipeline 2, a punching device 4 (see FIG. 4) can be attached to the branch outlet 1A2 of the upper frame 1A. . In FIG. 4, the drilling device 4 is a device that is detachably provided at the opening end of the branch outlet 1A2 through fastening or the like, and can form a branch opening having an inner diameter that is half the diameter of the existing pipeline 2. A hole saw 4A is provided. The hole saw 4 </ b> A can advance and retreat in the radial direction of the existing pipeline 2 via a feed mechanism (not shown), and can form a branch opening by advancing toward the existing pipeline 2.

In the present embodiment, the following procedure is used by using the branch portion forming adapter 1 having the above-described structure, according to the following procedure.
As shown in (1), a bypass pipe corresponding to a pipe other than the existing pipe 2 (indicated by reference numeral B for convenience) is laid between both ends of the cutoff section of the existing pipe 2. In FIG. 3, since the bypass pipe B is not yet connected, the existence of the bypass pipe B is indicated by a two-dot chain line. (1) The branch portion forming adapter 1 is provided at both ends of the cutoff section of the existing pipeline 2, that is, at a position where a branch opening for connecting the bypass pipe B is formed. The branching portion forming adapter 1 covers the outer periphery of the existing pipeline 2 by fastening the upper frame 1A and the lower frame 1A ', and has a closed space S inside.
(See FIGS. 1 and 2). FIG. 3 shows this state. At this time, the shutter device 3 (for convenience, in the drawings used in the following description, the shutter main body 3C shown in FIG. 2 is denoted by reference numeral 3 as a shutter device) is closed. Each end of the bypass pipe B is connected to the branch outlets 1A2 'of the lower frame 1A' of the adapter 1 for forming a branch located at both ends of the cutoff section of the existing pipeline 2. The bypass pipe B is introduced into a path to be detoured after a pressure resistance / airtightness test is completed in advance, and each end is connected to the branch outlet 1A2 '. Since the shutter device 3 'on the lower frame 1A' side where the bypass pipe B is connected is closed, the inflow of gas from the existing pipeline 2 is prevented.

(2) A branch opening is formed in the existing pipeline 2. FIG. 4 shows a state in which a branch opening is formed,
In the figure, of the branch outlets of each adapter 1 for forming a branch portion, a punching device 4 is provided at a branch outlet 1A2 on the side opposite to the side where the bypass pipe B is to be connected.
Is attached. The punch 4 is provided with a branch outlet 1A.
The center of the perforation can be changed in the laying direction of the existing pipeline 2 by the support base 5 provided on the pipe 2. As a configuration for changing the drilling center in the laying direction of the existing pipeline 2, although not shown, a rotating disk in which the rotation center and the drilling center are positioned eccentrically, or the drilling device 4 slides in the laying direction. A slider table or the like that can be used is used. The drilling device 4 can form a plurality of branch openings along the circumferential direction of the existing pipeline 2 by allowing the adapter 1 for forming a branch portion to rotate in the circumferential direction of the existing pipeline 2. Of the existing pipe line 2
, A plurality of branch openings can be perforated along the laying direction. FIG. 7 shows an example of a branch opening drilled by the punching device 4. The branch openings shown in FIG. 7 include a plurality of branch openings P1D formed in the circumferential direction and a branch opening formed along the laying direction. P1H
Are partially overlapped with each other. In particular, the branch opening P1H perforated in the laying direction is used when a support member of the blocking device 6 described later is inserted.

(3) After drilling, the chips remaining in the existing pipeline 2 are removed and the inner surface of the existing pipeline is ground and finished. FIG. 5 shows this state. In FIG. 5, the branch outlet 1 to which the punch 4 has been attached at the time of punching is shown.
In A2, when the perforation device 4 is removed, the shutter device 3 is closed, and then the grinding device 6 is attached to the branch outlet 1A2. Although not shown in detail, the grinding device 6 includes a rotary grinding blade 6A for roughing and semi-finishing that comes into contact with the inner surface of the existing pipeline 2, and grinds the inner surface of the existing pipeline 2 while rotating.

After the grinding, the grinding device 6 is removed from the branch outlet 1A2 and the shutter device 3 is closed,
Further, when the shutter device 3 'on the side of the lower frame 1A' is maintained in a closed state, before the shut-off device 7 described later is loaded, the branch pipe 1A2 'where the bypass pipe B is to be connected is located. Linked to each other. FIG. 6 shows a state where the bias tubes B are actually connected by solid lines. When the bypass pipe B is connected, the lower frame 1
Of the shutter devices 3 'on the A' side, the shutter device 3 'located on the upstream side in the gas flow direction indicated by the arrow in FIG. 6 may be opened. This shutter device 3 '
Is opened, gas from the existing pipeline 2 flows into the bypass pipeline B. For this reason, by providing an openable / closable opening in a part of the bypass conduit B on the downstream side in the gas flow direction, the opening is opened and the gas flowing into the bypass conduit B allows the gas to flow into the bypass conduit B. Can be purged and replaced with only gas. The connection of the bypass pipe B is as follows.
Not only after grinding but also before cutting of the existing pipeline after the blocking device 7 described later is loaded.

(4) After the grinding, when the grinding device 6 is detached from the branch outlet 1A2, the shutter device 3 is closed. From this state, the shutter device 3 is opened again, and the shut-off device 7 is inserted into the existing pipeline 2. Is inserted. FIG.
This state is shown, in which the shut-off device 7 is constituted by an inflatable bag which faces the gas flowing in the existing pipeline 2 and which is inflated from a support rod 7A to which it is attached. When the fluid is introduced, it expands and comes into close contact with the inner surface of the existing pipeline 2. FIG.
This figure shows the installation state of the shutoff device 7 inside the existing pipeline 2, and as shown in FIG.
An inflation pressure capable of standing upright inside the existing pipeline 2 is provided against the flow pressure of the gas indicated by the arrow. FIG. 7B shows the positional relationship between the branch opening and the blocking device 7. As described above, among the branch openings, the branch openings P1D that are adjacent in the circumferential direction are provided in the bag insertion portion of the blocking device 7. The branch opening P1H corresponds to the insertion portion of the support rod 7A. The blocking device 7 inserted into the existing pipeline 2 through each branch opening,
The support rod 7A is positioned by hitting the edge of the branch opening, and is expanded at that position.

(5) Both ends of the cutoff section in the existing pipeline 2 are cut by the cutoff device 7. FIG. 8 shows this state, in which the cutting position 2C of the existing pipeline 2 is cut by a cutter (not shown). When the existing pipeline 2 is cut, even if the cut-off position 7C of the existing pipeline 2 is opened by the shutoff device 7, a state in which gas does not leak is maintained.

(6) When the cutting position 2C in the existing pipeline 2 is sealed with a cap or welding, the shut-off device 7 is taken out of the existing pipeline 2. FIG. 9 shows this state. When the shutoff device 7 is taken out from the branch outlet 1A2, the shutter device 3 is closed.

(7) The shut-off device 7 is connected to the branch outlet 1A2
From the outlet, the branch outlet 1A2 is shielded by the plug 8 and then the branch outlet 1A
The shutter device 3 'on the side of the lower frame 1A' located on the side opposite to the side 2 is opened. FIG. 10 shows this state.
Since the cutting position in the existing pipeline 2 and the branch outlet 1A2 of the upper frame 1A are both sealed, the existing pipeline 2
Flows through the bypass line B into the existing line 2 on the rear side of the cutoff section.

According to the present embodiment, since the bypass pipeline B can be used as a new pipeline, simultaneous construction can be performed so that both the bypass pipeline and the new pipeline are used.
Moreover, since the shutter device 3 provided in the branch portion forming adapters 1 and 1 'has the same function as the open / close valve, the open / close valve (see FIGS. It is not necessary to provide a member (denoted by reference numeral V in FIG. 10). Thereby, the number of parts can be reduced.

On the other hand, as described above, the shut-off device 7 not only enables the erect pressure inside the existing pipeline 2 to resist the flow pressure of the gas by the inflation pressure, but also, for example, the support structure shown in FIG. Can also be used. In FIG. 11, a support rod 7A to which the bag of the shut-off device 7 is attached.
An extensible leg portion 7B is provided at the tip of the arm. The leg portion 7B has a habit of fitting into an engagement hole 2P formed on the peripheral surface of the existing pipeline 2. In this configuration, the support rod 7A inserted into the existing pipeline 2 from the branch opening
Is contracted when the leg 7B abuts against the inner surface of the existing pipeline 2, so that it does not hinder the insertion of the bag. On the other hand, when the leg 7B enters the engagement hole 2P by its own habit, the leg 7B is hooked on the existing pipeline 2 and is stopped. Thus, even when the flow pressure indicated by the arrow acts on the bag, the bag can be maintained upright against the flow pressure. In this configuration, the leg 7 is inserted into the engagement hole 2P.
Since the support rod 7A is in a cantilevered support state by the fitting of B, in order to further increase the support rigidity, the rim of the branch opening indicated by the symbol PS in FIG. 11 can abut the rear portion of the support rod 7A. What is necessary is just to set the formation form of the branch opening as described above. According to this, the support rod 7 is formed between the engagement hole 2P and the edge of the branch opening.
Since the both-ends supporting state supporting A is obtained, the supporting strength of the shut-off device 7 against the pressure in the pipe can be increased, and the upright state can be maintained more effectively.

On the other hand, the shutoff device 7 shown in FIG. 6 can be left in the existing pipeline 2. Such a use state corresponds to a case where the heat quantity conversion is performed in the existing pipeline, and for example, can be used as a sector valve in the existing pipeline. Therefore, there is an advantage that it is not necessary to prepare a sector valve at the time of gas replacement in the pipeline in the case of heat conversion.

[0030]

According to the first aspect of the present invention, a plurality of branch openings are provided along a circumferential direction and a laying direction of an existing pipeline by using a drilling device attached to a branch outlet provided in a drilling adapter. Therefore, the drilling operation can be performed without moving the drilling adapter with respect to the existing pipeline. This makes it unnecessary to replace the drilling adapter, thereby reducing the number of man-hours. In addition, since the perforated branch opening serves as an introduction portion of the grinding device and the shutoff device, it is not necessary to provide an opening for a working device of this kind again. Furthermore, since the shutter device can be opened and closed corresponding to each branch outlet, leakage at the time of replacement of various working devices can be minimized, and careless leakage can be reduced.

According to the second aspect of the present invention, by opening and closing the shutter device provided in the perforated adapter, the purging fluid can be flowed into the pipes other than the existing pipes. There is no need to construct a conduit for guiding the fluid for purging to a conduit other than the existing conduit apart from the conduit, and the configuration can be simplified.

According to the third aspect of the present invention, the shutoff device introduced into the existing pipeline from the perforated branch opening includes a bag that closely adheres to the inner surface of the existing pipeline and the bag against the pressure of the fluid. Since the supporting structure capable of maintaining the upright state in the existing pipeline is provided, the supporting strength of the bag in close contact with the inner surface of the pipeline is increased, and leakage can be efficiently prevented by maintaining the close contact of the bag.

According to the fourth aspect of the present invention, the shut-off device used for shutting off at the time of drilling or the like can be used for another purpose, so that a component for another purpose is prepared again. This eliminates the necessity and can reduce the operation cost.

[Brief description of the drawings]

FIG. 1 is a front view showing a state in which a branch portion forming adapter used in a branch opening forming apparatus according to an embodiment of the present invention is mounted on an existing pipeline.

FIG. 2 is a side view of the branch portion forming adapter shown in FIG. 1;

FIG. 3 is a schematic diagram showing a state before perforation using the branch portion forming adapter shown in FIG. 1;

FIG. 4 is a schematic view for explaining a state at the time of perforation using the branch portion forming adapter shown in FIG. 1;

FIG. 5 is a schematic diagram for explaining a state at the time of grinding after the end of the drilling operation shown in FIG. 4;

FIG. 6 is a schematic view showing a state in which an existing pipeline is cut off using the branch portion forming adapter shown in FIG. 1;

7A and 7B are views for explaining a positional relationship between a perforated branch opening and a blocking device, wherein FIG. 7A is a side view, and FIG. 7B is an arrow in a direction indicated by reference numeral (B) in FIG. FIG.

FIG. 8 is a schematic diagram showing a cut state of a cutoff section of an existing pipeline.

FIG. 9 is a schematic diagram showing a state in which the blocking device is taken out of an existing pipeline.

FIG. 10 is a schematic diagram showing a state in which a fluid is introduced into a pipeline other than an existing pipeline.

FIG. 11 is a schematic diagram showing a modification of the blocking device used in the blocking state shown in FIG. 6;

[Explanation of symbols]

Reference Signs List 1 Adapter for forming a branch portion corresponding to a perforated adapter 1A Upper frame 1A 'Lower frame 1A2, 1A2' Branch outlet 2 Existing pipe line 2P Engagement hole for leg of blocking device 3, 3 'Shutter device 3A, 3A' Sealing Stop box member 3B, 3B 'Sliding rod 3C, 3C' Shutter body 4 Drilling device 4A Hole saw 6 Grinding device 7 Blocking device 7A Support rod 7B Leg 8 Plug plug B Bypass pipe

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 000230526 Nihon Victoria Co., Ltd. 2-1-1 Uchisaiwaicho, Chiyoda-ku, Tokyo (72) Inventor Yoshio Akiyama 17-1 Hommachi, Fussa-shi, Tokyo Takeyo Gas Co., Ltd. Inside the company (72) Inventor Satoshi Maeda 2-17-4 Kuramae, Taito-ku, Tokyo Kawatetsu techno construction Co., Ltd. (72) Inventor Akira Adachi 2-17-4 Kuramae, Taito-ku, Tokyo Kawatetsu techno construction stock Inside the company (72) Inventor Masahiko Yoneda 2-17-4 Kuramae, Taito-ku, Tokyo Inside Kawatetsu Techno Construction Co., Ltd. (72) Inventor Akihito Mouri 2-19-6 Nakaikegami, Ota-ku, Tokyo Oogami Precision Stock In-house (72) Inventor Takamitsu Suzuki 2-19-6 Nakaikekami, Ota-ku, Tokyo Daigo Precision Co., Ltd. (72) Inventor Shintaro Ikeda 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Tokyo Marine Building Japan Victoria Co., Ltd. (72) Inventor Yuji Noda 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Tokyo Marine Building (72) Inventor Akifumi Kono 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Tokyo Marine Building F-term (reference) 3H025 DA02 DB18 DC02 DD01

Claims (4)

[Claims] 1. A construction method for perforating a branch opening having substantially the same diameter as an existing pipeline in a part of a section where the existing pipeline is laid, and connecting a bypass pipeline or a new pipeline to the perforated portion. A closed space is formed between the outer circumference of the existing pipeline and the outer peripheral surface of the existing pipeline when they are attached to both ends of the cutoff section in the existing pipeline, respectively, at positions opposed to each other in the circumferential direction of the existing pipeline in the closed space. Using a perforated adapter having a branch outlet and incorporating a shutter device for controlling a communication state between the branch outlet and the closed space, connecting a pipeline other than an existing pipeline to one of the branch outlets. A drilling device and a grinding device used after drilling are attached to the branch outlet on the side opposite to the branch outlet on the side to which the pipelines other than the existing pipeline are connected in the working order, and at least the drilling device is Existing pipe A plurality of branch openings are formed along the circumferential direction and the laying direction while being mounted so as to be displaceable in the circumferential direction and the laying direction, and after the grinding, the shutoff device for sealing both ends of the cutoff section in the existing pipeline is provided. When the grinding device is inserted into the existing pipeline from the branch outlet on the side to which the grinding device is attached, and at the time when each end of the cutoff section in the existing pipeline is divided and sealed, the barrier device is removed from the branch outlet. When it is removed, after the shielding of the branch outlet is completed, the shutter device on the branch outlet side to which the pipeline other than the existing pipeline is connected is opened to allow the fluid from the existing pipeline into the pipeline. A pipe laying method characterized by introduction. 2. The pipe laying method according to claim 1, wherein a flow direction of a fluid flowing through the existing pipeline is included in a branch outlet side shutter device to which a pipeline other than the existing pipeline is connected. A pipe laying method characterized by flowing a purging fluid into a pipeline other than an existing pipeline by opening a shutter device located on an upstream side after grinding. 3. The pipe laying method according to claim 1, wherein the blocking device includes an inflatable bag,
The bag has a support structure that stands upright in a direction perpendicular to the flow direction of the fluid against the pressure of the fluid flowing through the existing pipeline and maintains the bag in close contact with the inner surface of the existing pipeline. A pipe laying method characterized by the following. 4. The pipe laying method according to claim 3, wherein the shut-off device can be left or taken out of an existing pipe line.