JP2002022062A - Opening method of branch of existing pipeline - Google Patents

Abstract

(57) [Summary] [Problem] In view of the problem at the time of reopening the branch opening when targeting the pipeline where the inner surface of the pipeline is lined,
Provided is a method of opening a branch of an existing pipeline, which can easily and accurately determine the position of the branch opening. A branch part opening method for reopening a branch opening 1A covered with a lining film R for an existing pipeline 1 having a lining film R formed on an inner surface thereof,
Before the lining of the existing pipeline 1, the branch opening 1A
A cap member 2 made of a material that is electrically and / or magnetically distinguishable from a portion other than the position of the branch opening 1A.
After the lining work, the piercing means 3 introduced into the existing pipeline 1 is equipped with a detecting means 3A capable of detecting the position of the cap member 2, and the position of the cap member 2 is detected by the detecting means 3A. Is detected, the drilling operation is started, and the branch opening 1A is restarted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of opening a branch portion of an existing pipeline, and more particularly to a method of determining a position of a branch opening to restart a branch opening covered by a lining film.

[0002]

2. Description of the Related Art In a metal pipeline such as a cast iron pipe buried underground, if a corrosion hole is formed in a part due to aged deterioration or the like, gas or the like leaks from the part. Therefore, conventionally, an in-pipe lining method for lining a resin film on the inner surface of an existing pipeline having such a portion is known. In some cases, a branch pipe is connected to a part of an existing pipeline targeted for lining construction. For this reason, if lining is performed, the branch opening communicating with the existing pipeline will be closed by the lining film. After the lining, it is necessary to restart the branch opening covered by the lining film to maintain the communication state between the branch pipe and the existing pipeline. As a method of restarting the branch opening, there are a case where drilling is performed from the branch pipe side located outside the pipeline and a case where drilling is performed from inside the pipeline. When drilling from outside the pipeline, it is necessary to cut the ground in that part, so there is a problem that additional work such as backfilling will be increased, so drilling from the inside of the pipeline will require a lot of man-hours. Above. When piercing from inside the conduit, it is necessary to determine the position of the branch opening covered by the lining membrane. As an example of the method of determining the position of the branch opening, a camera that can photograph the inside of the pipe before lining construction is introduced, the camera is moved from the opening end of the pipeline located at the starting position, and the moving distance to the position of the branch opening And the features in the pipe at that position, such as the size of the branch opening that can be predicted to have a dent that slightly changes the smoothness of the lining film, and after lining construction, the features at the position corresponding to the above moving distance There is a method of making a determination, determining a branch position, and piercing.

FIGS. 4 to 6 are diagrams showing an example of determining the position of a branch opening for a water distribution pipe.
FIG. 5 shows a state in which a branch position in the circumferential direction of the water distribution pipe P is determined, and FIG. In FIG. 5, the distance (L) from the opening end of the water distribution pipe P to the branch position and the angle (θ) in the circumferential direction at the branch position are mapped in advance, and the drilling work robot introduced into the pipe (illustrated) Is compared with the mapped distance (L1), and the position where the difference between both distances disappears is determined as the branching position in the laying direction, and the direction in which the water W accumulates at that position is determined. The branch opening P1 is pierced by sending the piercing drill toward the peripheral wall at an angle (θ1) mapped as a reference. When the lining film is perforated, the branch opening P1 to which the branch pipe is connected is restarted as shown in FIG.

[0004]

In the method for determining the position of the branch opening shown in FIGS. 4 to 6, the circumferential position for piercing the branch opening is determined by the position of the water W accumulated on the lower surface of the water distribution pipe P. Although the index is determined based on the radius connecting the position and the center of the pipeline, for example, unlike a water distribution pipe, in a pipeline targeting gas that does not accumulate on the lower surface, the above-described method may be used. Can not. In particular, when lining is performed on the inner surface of the pipeline, for example, even if a visually identifiable member is provided at the branch position, it will be covered with the lining film, and it will be difficult to determine the position after lining. Become.

SUMMARY OF THE INVENTION An object of the present invention is to provide an easy and easy method for reopening a branch, particularly in the case of the conventional branch opening method described above, particularly in a case where the inner surface of the pipeline is lined. It is an object of the present invention to provide a method of opening a branch portion of an existing pipeline in which the position of the branch opening can be accurately determined.

[0006]

In order to achieve this object, according to the first aspect of the present invention, a branch opening covered by a lining film is restarted for an existing pipeline in which a lining film is formed on an inner surface. In the branch opening method, a cap member made of a material that can be electrically and / or magnetically distinguishable from a position other than the position of the branch opening is filled in the branch opening before lining the existing pipeline. After the lining, the drilling means introduced into the existing pipeline is provided with a detecting means capable of detecting the position of the cap member, and the drilling work is started by detecting the position of the cap member by the detecting means. Then, the branch opening is restarted.

According to a second aspect of the present invention, in the method for forming a branch of an existing pipeline according to the first aspect, the existing pipeline is intended for a pipeline through which gas flows.

[0008]

According to the first and second aspects of the present invention, the lining is formed by inserting a cap member made of a material that can be electrically and / or magnetically distinguishable from a portion other than the position of the branch opening before the lining is performed. Even after construction,
The position of the cap member can be searched and perforated.
In particular, even when targeting a gas pipeline having completely different properties from water or the like used as a reference for determining a branch position inside as an existing pipeline, only the exploration of the cap member is sufficient, so that the distance of movement and the circumferential direction may be different. It is not necessary to map the angles of the images in advance.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram for explaining one step of a branch part opening method according to an embodiment of the present invention.
In the figure, the branch opening 1A in the existing pipeline 1 has:
Prior to lining, a cap member 2 made of a material that can be electrically and / or magnetically distinguished between the position of the branch opening 1A and other parts is loaded. The cap member 2 is made of a conductive or magnetic material when the existing pipeline 1 is an electrically insulating material, and is used when the existing pipeline 1 is a conductive material such as metal. An insulating material is used. In the example shown in FIG. 1, a rubber cap made of rubber mixed with magnetic powder is used. The existing pipe 1 made of a conductive material such as a metal pipe.
In this case, it is also possible to change the specification of the material by applying a treatment to the cap member so that the position of the branch opening 1A can be distinguished from other positions. In the case of a tube, if the cap member 2 is made of a structure in which magnetic powder is mixed, the outer peripheral wall of the cap member 2 is made of a non-magnetic material, a material that does not have magnetic permeability, or an electrically insulating material, and a branch opening is formed inside. It is also possible to use a material having higher magnetic characteristics or electrical insulation characteristics than the other portions to distinguish it from the portions other than the branch openings.

In order to load the cap member 2 into the branch opening 1A, an in-pipe mobile robot 3 equipped with a cutter for drilling a branch after lining is used.
The branch opening 1A is detected using an image pickup means such as a camera, and the cap member 2 prepared in the drilling arm or the like is fitted into the branch opening 1A.

FIG. 2 shows a state after the inner surface of the existing pipeline 1 is lined and a lining film R is formed on the inner surface of the pipeline.
Is shown in In FIG. 2, after the lining work, the in-pipe mobile robot 3 is introduced again into the existing pipeline 1. In this case, the in-pipe mobile robot 3 is provided with detecting means 3A for detecting an electrical and / or magnetic reaction based on the material of the cap member 2. As the detecting means 3A, a sensor capable of detecting a dielectric constant, a magnetic permeability, or the like is used. The detecting means 3A includes a discriminating means (not shown) that can detect a change in the dielectric constant or the magnetic permeability in the cap member 2 loaded in the branch opening 1A as a change in the current value, and has the largest change. The position is determined as the position of the branch opening 1A. When the change in the dielectric constant is used, the determination is made in consideration of the change due to the presence of the lining film R.

When the position of the branch opening 1A is determined by the detecting means 3A, the branch opening 1A is pierced from the inside of the lining film R using a piercing machine (not shown) provided in the in-pipe mobile robot 3. It is restarted to communicate the branch pipe with the inside of the existing pipeline 1 (see FIG. 3).

[0013]

According to the first and second aspects of the present invention,
Before the lining work, the position of the cap member can be searched even after the lining work by inserting a cap member made of a material that can be electrically and / or magnetically distinguishable from the part other than the branch part formation planned position with respect to the branch opening. Can be perforated. In particular, even when targeting a gas pipeline having completely different properties from water or the like used as a reference for determining a branch position inside as an existing pipeline, only the exploration of the cap member is sufficient, so that the distance of movement and the circumferential direction may be different. There is no need to previously map the angle of the object, etc., and it is only necessary to detect electrical and / or magnetic changes directly in the pipeline. As a result, it becomes possible to determine the branch opening in accordance with the actual situation in the pipe, and it is possible to accurately and easily restart the branch opening with less erroneous determination as in the visual case.

[Brief description of the drawings]

FIG. 1 is a schematic view for explaining one step of a branch portion forming method according to an embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining a state of exploring a branch portion in a branch portion forming method according to an embodiment of the present invention.

FIG. 3 is a schematic diagram showing a perforation formed at a position detected by the branch portion search shown in FIG. 2;

FIG. 4 is a schematic diagram for explaining one aspect of a conventional branch part indexing method.

FIG. 5 is a diagram for explaining the principle used in the branching unit indexing method shown in FIG. 4;

FIG. 6 is a schematic diagram showing a state of a branch formed at a position determined by the branch part determining method shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Existing pipeline 1A Branch opening 2 Cap member 3 In-pipe mobile robot 3A Detection means R Lining film

Claims (2)

[Claims] 1. A branch opening method for reopening a branch opening covered by a lining film for an existing pipeline in which a lining film is formed on an inner surface, wherein the branch is formed before lining of the existing pipeline. The opening is filled with a cap member made of a material that can be electrically and / or magnetically distinguishable from a portion other than the position of the branch opening, and after lining, the cap is inserted into the perforating means introduced into the existing pipeline. A branching section of the existing pipeline, wherein the branching section is provided with detecting means capable of detecting the position of the member, and the detecting means detects the position of the cap member to start drilling work and restart the branching opening. Opening method. 2. The branch opening method for an existing pipeline according to claim 1, wherein the existing pipeline is a pipeline through which gas flows.