JP2013064485A - Connection pipe for putting in and replacing new and old pipes for buried pipe and construction method for putting in and replacing new and old pipes for buried pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection pipe, by which a new pipe and an old pipe can be easily connected correspondingly to a height difference and plane positions of the new pipe and the old pipe that are different at each job site, and which can be repeatedly used.SOLUTION: A connection pipe includes: a first connection pipe 12 connected to an end of a new pipe P2 via a first joint 11; a second joint 13 connected to an end of an old pipe P1; a second connection pipe 14 connected to the old pipe P1 via the second joint; and a third joint 15 for connecting the end of the first connection pipe and the end of the second connection pipe. The first connection pipe and the second connection pipe include bent parts 12d, 12e, 14d, 14e for connecting each of a pair of lateral pipe parts 12a, 12b, 14a, 14b along the new pipe or the old pipe, vertical pipe parts 12c, 14c provided between the lateral pipe parts, and the lateral pipe parts to both ends of the vertical pipe parts. The third joint connects the end of the first connection pipe and the end of the second connection pipe while an intersection angle between the lateral pipe part 12c of the first connection pipe and the vertical pipe part 14c of the second connection pipe is arbitrarily adjusted.

Description

  The present invention relates to a method for replacing and replacing an old pipe and a new pipe buried in the ground, a connecting pipe connecting the end of the old pipe and the end of the new pipe, and an old and new pipe replacement using this connecting pipe. It relates to the construction method.

  Gray cast iron pipes have long been used for buried gas pipes in Japan. This gray cast iron pipe is relatively resistant to corrosion in the state of coated or uncoated bare pipe, but on the other hand, it is vulnerable to impacts, so it may be subject to high wheel loads or earthquakes. In some places, work is underway to replace the old gray cast iron pipe with a new polyethylene (PE) pipe.

  In such replacement work of old and new pipes, old pipes buried over long distances cannot be replaced with new pipes at the same time. The end of the new pipe that has been newly extended and the end of the old pipe that has not been constructed are connected to each other to ensure gas distribution between the old and new pipes. This makes it possible to supply gas to both the supply branch branched from the buried new pipe and the supply branch branched from the existing old pipe when the construction is suspended.

  At this time, the old pipe is buried at a depth of about 1.2m underground, while the new pipe is buried at a relatively shallow depth (about 0.6m underground). In order to connect the end of the old pipe that has not yet been constructed, a connecting pipe is required to absorb the difference in the laying position (height difference) between the two pipes.

  Prior art connection pipes (temporary connection pipes) described in the following Patent Document 1 are prepared by arranging as few temporary connection pipe members as possible as possible, so that the old pipe and the new pipe having a height difference as described above can be obtained. Are provided with two elbows detachably connected to the end of the old pipe and the end of the new pipe through first and second pipe joints, respectively. One or a plurality of straight short pipes are connected between them.

JP 2001-141111 A

  The new pipe will be laid along the laying position of the existing old pipe, but when burying the new pipe, it is necessary to avoid interference with various underground structures. Therefore, the difference in height between the new pipe and the old pipe is not always constant. In addition, when the installation positions of the new pipe and the old pipe are viewed in plan, the new pipe is not always installed directly above the old pipe. In particular, when the old pipe is removed in the replacement work of the old and new pipes, the new pipe is preferably arranged at a position shifted in plan from the laying position of the old pipe. In this way, the relationship between the laying position of the old pipe and the new pipe is generally different for each site, and the temporary connection pipe that connects the end of the new pipe and the end of the old pipe is individually handled for each site. In other words, there was a problem that the temporary connecting pipe used at one site could not be used at another site.

  On the other hand, as in the prior art described above, if a plurality of straight short pipes having a specified length are connected to absorb the difference in height between the new pipe and the old pipe, the length of the short pipe must be finely divided. Therefore, it is impossible to cope with various height differences, and this causes a problem that requires a great amount of labor to connect the temporary connecting pipe. In addition, when the length of the short pipe is set in advance, there is a problem that it is not possible to accurately cope with the height difference between the new pipe and the old pipe that are different at each site.

  This invention makes it an example of a subject to cope with such a problem. In other words, when replacing the old and new pipes buried in the ground, the connecting pipes that connect the end of the old pipe and the end of the new pipe are different from each other at the site. The object of the present invention is that the new pipe and the old pipe can be easily connected in accordance with the difference and the plane position, and the laying position of the new pipe and the old pipe can be repeatedly used in various sites. is there.

  In order to achieve such an object, the present invention comprises at least the following configuration.

  A connecting pipe for connecting an end of an existing old pipe and an end of a new pipe to be newly used, which is used in a construction for replacing an old pipe and a new pipe buried in the ground, A first joint connected to the end of the first pipe, a first coupling pipe connected to the end of the new pipe via the first joint, a second joint connected to the end of the old pipe, A second connecting pipe connected to the old pipe via the second joint; a third joint connecting the end of the first connecting pipe and the end of the second connecting pipe; Each of the pipe and the second connecting pipe includes a pair of horizontal pipe parts along the new pipe or the old pipe, a vertical pipe part provided between the pair of horizontal pipe parts, and the pair of horizontal pipe parts. A pair of bent portions connected to both ends of the vertical pipe portion are provided, and the third joint can arbitrarily set an intersection angle between the vertical pipe portion of the first connection pipe and the vertical pipe portion of the second connection pipe. In integer state, characterized by connecting the ends of the second connecting pipe and the end portion of the first connection pipe.

  According to the old and new connecting pipes for replacement of buried pipes having such characteristics, the other end and one end of the first connecting pipe whose one end is connected to the new pipe via the first joint are connected to the old pipe. The other end of the second connecting pipe connected via the two joints is connected via the third joint, and the crossing angle between the vertical pipe of the first connecting pipe and the vertical pipe of the second connecting pipe is arbitrarily set. Since the end of the first connecting pipe and the end of the second connecting pipe are connected by the third joint in the adjusted state, the difference in the laying position between the new pipe and the old pipe is It can be absorbed by adjusting the crossing angle of the vertical pipes of the two connecting pipes.

  As a result, when replacing the old pipe and the new pipe buried in the ground, the connecting pipe that connects the end of the old pipe and the end of the new pipe will be different for each site. New pipes and old pipes can be easily connected to accommodate height differences and planar positions. In addition, the connecting pipe can be used repeatedly at various sites where the new pipe and the old pipe are laid.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing (side view) which showed the old and new pipe insertion connecting pipe of the buried pipe which concerns on one Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing (front view) which showed the old and new pipe insertion connecting pipe of the buried pipe which concerns on one Embodiment of this invention. The explanatory view (side view) which showed the modification of the connecting pipe concerning the embodiment of the present invention. Sectional drawing which showed the structural example of the 1st-3rd coupling in embodiment of this invention. Explanatory drawing explaining the old and new pipe insertion replacement construction method of the buried pipe using the connection pipe which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIGS. 1 and 2 are explanatory views showing a connecting pipe for replacing old and new pipes according to an embodiment of the present invention (FIG. 1 is a side view, and FIGS. 2 (a) to 2 (c) are front views. Is shown.)

  A connecting pipe for replacement of old and new pipes (hereinafter simply referred to as connecting pipe) 1 is used for the construction of replacing the old pipe P1 and the new pipe P2 buried in the ground, and is connected to the end of the existing old pipe P1. The end of the new pipe P2 to be newly buried is connected. The old pipe P1 here is, for example, an existing gray cast iron pipe, and the new pipe P2 is a polyethylene (PE) pipe that replaces the gray cast iron pipe.

  The connecting pipe 1 includes a first joint 11 connected to the end of the new pipe P2, a first connecting pipe 12 connected to the end of the new pipe P2 via the first joint 11, and an old pipe P1. The second joint 13 connected to the end, the second connecting pipe 14 connected to the old pipe P1 via the second joint 13, the end of the first connecting pipe 12 and the end of the second connecting pipe 14 The third joint 15 is connected.

  The first connecting pipe 12 includes a pair of horizontal pipe parts 12a and 12b along the old pipe P1 or the new pipe P2, a vertical pipe part 12c provided between the pair of horizontal pipe parts 12a and 12b, and a pair of horizontal pipe parts 12a. , 12b are provided with a pair of bent portions 12d, 12e for connecting the both ends of the vertical tube portion 12c. Similarly, the second connecting pipe 14 has a pair of horizontal pipe portions 14a and 14b along the old pipe P1 or the new pipe P2, and a pair of vertical pipe portions 14c provided between the pair of horizontal pipe portions 14a and 14b. A pair of bent portions 14d and 14e are provided to connect each of the horizontal tube portions 14a and 14b to both ends of the vertical tube portion 14c. Both the first connecting pipe 12 and the second connecting pipe 14 can be formed of a plastic pipe such as a polyethylene pipe.

  In the connecting pipe 1 having such a configuration, the third joint 15 is in a state in which the intersecting angle of the vertical pipe portion 12c of the first connecting pipe 12 and the vertical pipe portion 14c of the second connecting pipe 14 is arbitrarily adjusted, The end of the first connecting pipe 12 and the end of the second connecting pipe 14 are connected. Thereby, when there is a height difference H in the laying position of the old pipe P1 and the new pipe P2, this height difference H is refracted by the vertical pipe portion 12c of the first connecting pipe 12 and the vertical pipe portion 14c of the second connecting pipe 14. It can be absorbed by adjusting the state.

  As shown in FIG. 2A, when the height difference H1 between the old pipe P1 and the new pipe P2 is relatively large, the vertical pipe part 12c of the first connecting pipe 12 and the vertical pipe part 14c of the second connecting pipe 14 are used. Can be dealt with by relatively increasing the crossing angle θ1 of the first connecting pipe, as shown in FIG. 2B, when the height difference H2 between the old pipe P1 and the new pipe P2 is relatively small. This can be dealt with by making the crossing angle θ2 of the 12 vertical tube portions 12c and the vertical tube portion 14c of the second connecting tube 14 relatively small. Further, even when there is a planar interval V1 at the laying position of the old pipe P1 and the new pipe P2, the vertical pipe portion 12c of the first connecting pipe 12 and the vertical pipe of the second connecting pipe 14 according to the interval V1. Adjustment is possible by adjusting the intersection angle θ3 of the portion 14c. That is, even if the relationship between the laying positions of the old pipe P1 and the new pipe P2 is different for each site, it is possible to connect the old pipe 1 and the new pipe 2 with one connecting pipe 1.

  FIG. 3 shows a modification of the connecting pipe 1 according to the embodiment of the present invention. In the connecting pipe 1, the directions of the bent part 12 d and the bent part 12 e in the first connecting pipe 12 may be reversed as illustrated. In this case, the directions of the bent portion 14d and the bent portion 14e in the second connecting pipe 14 are also reversed as shown in the drawing. Moreover, the length of the vertical pipe part 12c of the 1st connection pipe 12 and the vertical pipe part 14c of the 2nd connection pipe 14 may be made into the same length like the example shown in FIG.1 and FIG.3, The vertical pipe portion 12c may be longer (or shorter) than the other vertical pipe portion 14c.

  FIG. 4 is a cross-sectional view illustrating a configuration example of the first to third joints. The first joint 11, the second joint 13, and the third joint 15 can be constituted by a mechanical joint that is detachable with respect to the old pipe P1 or the new pipe P2, and can ensure the gas tightness of the gas flow. Further, any form of mechanical joint may be used as long as the pipe to be connected can be rotated around the pipe axis before connection. A general mechanical joint for connecting a gas pipe has such a requirement.

  Here, the third joint 15 that connects the first connecting pipe 12 and the second connecting pipe 14 formed of a polyethylene pipe will be described as an example, but the first joint 11 and the second joint 13 are also constituted by similar joints. can do. When the old pipe P1 is a gray cast iron pipe and the second connecting pipe 14 is a polyethylene pipe, the second joint 13 has a joint configuration for connecting the gray cast iron pipe and the polyethylene pipe.

  The third joint 15 has an end of the first connecting pipe 12 inserted into one end of the joint pipe 15A, and an end of the second connecting pipe 14 inserted into the other end of the joint pipe 15A. 12. Insert sealing members 15B (backup ring), 15C (round rubber ring), 15D (square rubber ring) between the outer periphery of the second connecting pipe 14 and press it with the pusher wheel 15E to ensure airtightness. Further, the flange portion 15A1 of the joint pipe 15A and the flange portion 15E1 of the presser wheel 15E are fastened by a bolt nut 15F. At this time, the reinforcing inner pipes 12X and 14X are inserted inside the ends of the first connecting pipe 12 and the second connecting pipe 14 to be connected, and lock rings 12Y and 14Y are mounted on the outer periphery thereof. Further, coloring rings 12Z and 14Z are mounted.

  Hereinafter, based on FIG. 5, the new and old pipe insertion replacement method of the buried pipe using the connecting pipe 1 which concerns on embodiment of this invention is demonstrated. Here, the construction method related to the work for one time in the old and new pipe replacement work performed in several steps will be described. In the first stage of this one-time construction, a part of the existing old pipe is replaced by a new pipe, and the end of the new pipe and the end of the old pipe not yet constructed are connected by the connecting pipe 1.

  First, with the start of the construction, a construction section for one time is set, and the old pipe buried in the construction section is opened (S1). Thereafter, a gas bag is inserted into the old pipe outside the construction section to cut off the gas flow in the construction section (S2), and the old pipe is cut downstream of the gas supply in the construction section (S3).

  Next, the new pipe is extended into the construction section (S4). That is, the end of a new pipe that has already been buried is closed, the connecting pipe 1 is removed, and the end of the new pipe that is newly extended is connected to the end of the new pipe. Then, the branch pipe to the gas supply destination in the construction section is connected to the new pipe newly extended to the construction section (S5).

  Next, the end of the cut old pipe and the end of the extended end of the new pipe are connected by the connecting pipe 1 on the gas supply downstream side of the construction section (S6). At this time, the connecting pipe 1 can be repeatedly used in the previous construction, and the crossing angle of the vertical pipe portion 12c of the first connecting pipe 12 and the vertical pipe portion 14c of the second connecting pipe 14 is determined. While adjusting, both ends of the connecting pipe 1 are connected to the end of the old pipe and the end of the new pipe, respectively. Thereafter, the gas bag inserted into the old pipe is removed, and gas distribution between the old pipe and the extended new pipe outside the construction section is secured (S7). Thereafter, the construction section is backfilled (S8), and the current construction is completed.

  According to the new and old pipe insertion and replacement method using the connecting pipe 1 according to the embodiment of the present invention, even if the relationship between the laying positions of the old pipe and the new pipe is different for each construction, the first connecting pipe 12 is used. By adjusting the crossing angle of the vertical pipe portion 12c and the vertical pipe portion 14c of the second connecting pipe 14, it is possible to cope with one connecting pipe 1. Accordingly, one connecting pipe 1 can be used repeatedly, and labor and cost for recreating the connecting pipe corresponding to the site for each construction can be reduced, and further, waste of resources can be reduced.

  In addition, the connection of the connecting pipe 1 at the site is performed by simply connecting the first joint 11 and the second joint to the new pipe P2 and the old pipe P1 with the third joint 15 loosened, and then tightening the third joint 15. Therefore, a complicated operation of connecting a plurality of short tubes is unnecessary, and the connecting operation of the connecting tube 1 can be performed very easily.

  Furthermore, the connecting pipe 1 according to the embodiment of the present invention is not provided until the intersecting angle of the vertical pipe part 12c of the first connecting pipe 12 and the vertical pipe part 14c of the second connecting pipe 14 is close to zero from 180 degrees. Adjustment in stages is possible. As a result, the adjustment range can be widened and adjustment with high accuracy is possible as compared with the case where the expansion tube and the short tube are connected.

  In addition, although the above description has described the replacement of the old and new gas pipes, the same applies to water pipes and other fluid transport pipes, and the present invention is not particularly limited to gas pipes. .

1: Connecting pipe (connecting pipe for replacing old and new pipes),
11: 1st coupling, 12: 1st connecting pipe, 13: 2nd coupling, 14: 2nd connecting pipe,
15: Third connecting pipe,
12a, 12b, 14a, 14b: horizontal tube portion,
12c, 14c: Vertical pipe part,
12d, 12e, 14d, 14e: bent part,
P1: Old pipe, P2: New pipe

Claims (4)

A connecting pipe that connects the end of an existing old pipe and the end of a new pipe that is used to replace the old pipe and the new pipe that are buried in the ground.
A first joint connected to an end of the new pipe;
A first connecting pipe connected to the end of the new pipe via the first joint;
A second joint connected to an end of the old pipe;
A second connecting pipe connected to the old pipe via the second joint;
A third joint connecting the end of the first connecting pipe and the end of the second connecting pipe;
Each of the first connecting pipe and the second connecting pipe includes a pair of horizontal pipe parts along the new pipe or the old pipe, a vertical pipe part provided between the pair of horizontal pipe parts, and the pair of horizontal pipes. A pair of bent portions connecting each of the portions to both ends of the longitudinal tube portion,
The third joint has an end portion of the first connecting pipe and the second connecting pipe in a state where an intersecting angle between the vertical pipe portion of the first connecting pipe and the vertical pipe portion of the second connecting pipe is arbitrarily adjusted. Connecting pipe for replacing old and new pipes, characterized by connecting the ends of the pipes.   The connection pipe for replacing old and new pipes according to claim 1, wherein the first connection pipe and the second connection pipe are formed of polyethylene pipes.   The connecting pipe for replacing old and new pipes according to claim 1 or 2, wherein the first joint, the second joint, and the third joint are constituted by mechanical joints. A new and old pipe insertion / replacement method using a new and old pipe insertion / replacement connecting pipe according to claim 1,
Inserting a gas bag into the old pipe outside the set construction section to cut off the gas flow in the construction section, and cutting the old pipe on the gas supply downstream side of the construction section;
Connecting a branch pipe to a gas supply destination in the construction section to a new pipe extended to the construction section;
Connecting the cut end portion of the old pipe and the extended end portion of the new pipe with the old and new pipe replacement connecting pipe on the gas supply downstream side of the construction section;
Removing the gas bag inserted into the old pipe, and ensuring gas flow between the old pipe and the new pipe outside the construction section,
The old and new pipe connecting and connecting pipes are configured to adjust the crossing angle between the vertical pipe part of the first connecting pipe and the vertical pipe part of the second connecting pipe, and the end of the old pipe and the end of the new pipe. New and old pipe replacement method for buried pipes, characterized by being connected to

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