JP2008223860A - Pipe joint structure for sleeve jacking method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent pressure loss of a rubber ring 6 without enlarging diameter of SII type joint for jacking. <P>SOLUTION: A space retention material 8 is fitted in a front side of a flange 20 with a roller 24 of a spigot 1, and a propulsion force transmission member 30 is provided in a front side of the space retention material 8. The propulsion force transmission member 30 comprises a ring shape member 31 abutted on a front side end surface of the space retention material 8, and a projection member 32 passing through a pressing ring 9 from the member 31 and abutting on a socket end surface 2a. Propulsion force is directly transmitted to a socket 2 via the space retention material 8 and the propulsion force transmission member 30, and there is no risk of pressure loss of the rubber ring or the like by the propulsion force and press-in of the spigot not to obstacle water tightness of the rubber ring. When the transmission member 32 passes through the pressing ring 9, it is not necessary to project the transmission member 32 to an outside of the pressing ring 9. The space retention member 8 has strength to transmit propulsion force, and contracts or breakage against strong compression force such as earthquake to allow insertion of the spigot to the socket. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a seismic-proof propulsion pipe joint structure used for a pipe propulsion method in which a pipe for transporting fluid used for water supply, gas, sewerage, etc. is laid without opening.

  As a method of embedding fluid transport pipes such as ductile cast iron pipes, the open-cut method of excavating and laying the ground has been common, but nowadays traffic volume has increased not only on main roads but also on general roads. Therefore, it is difficult to block traffic due to the open-cut method. For this reason, only the starting and reaching shafts are excavated, and a fume pipe or steel pipe is pushed and buried as a sheath pipe (sheath pipe), then a ductile cast iron pipe is inserted, or an existing pipe is used as a sheath pipe. A propulsion method such as a pipe-in-pipe method (PIP method) in which a new pipe having a small diameter is inserted therein to renew the pipe line has been widely adopted.

  In the pipe-in-pipe method, as shown in FIG. 9, a new pipe P having a smaller diameter than that in the existing pipe P ′ embedded in the underground W between the start pit S and the arrival mine R is provided. The hydraulic jack J is installed in the starting pit S, the rear part of the hydraulic jack J abuts against the reaction force receiving H, and the front part presses the new pipe P through the pushing angle B. It has become. The new pipe P is sequentially joined by inserting the insertion port 1 at the tip end thereof into the receiving port 2 at the rear end part of the preceding new pipe P, and is pushed into the existing pipe P ′. A leading sled K for reducing the insertion resistance is attached to the tip of the leading new pipe P.

  Since the existing pipe in this pipe-in-pipe construction method is one of the sheath pipes P ′, in this specification (including the description of “Claims”), the sheath pipe propulsion method shown in FIG. Unless otherwise specified, a construction method that pushes and inserts a new pipe P into a sheath pipe P ′ to form a double pipe structure, such as a pipe-in-pipe construction method, is generally referred to as a “sheath pipe construction method”.

On the other hand, in recent years, pipe lines are also required to have earthquake resistance. As a pipe joint structure having such earthquake resistance, for example, as shown in FIGS. 10 and 11, the insertion opening 1 can be expanded and contracted within a required range. (Can be inserted and removed). In this pipe joint, an insertion port 1 with a projection 3 is inserted into a receiving port 2 with a lock ring 5 through a rubber ring 6, and an end surface (flange) 2 a of the receiving port 2 and a push ring 9 are connected by a T bolt 7. By passing through and screwing in the nut 7a at the tip, the push ring 9 approaches the receiving end face 2a, and the rubber ring 6 is pushed in to improve the watertightness. Further, a flange 20 with a roller 24 is fitted on the outer peripheral surface of the insertion port 1 that has come out from the receiving port 2, and a spacing member 8 is interposed between the flange 20 and the push ring 9 (Patent Document 1). 10).
JP 2002-276284 A

In this pipe joint structure, during propulsion, the roller 24 of the flange 20 rolls on the inner surface of the sheath pipe P ′ to guide the pipe P, and as shown in FIG. The tip (projection 3) is maintained in the middle of the expansion / contraction allowance L. When the ground changes due to an earthquake or the like, with respect to the pulling-out force of the insertion slot 1, the insertion slot 1 is retracted (pulled out) by an extension allowance L _{1 in} which the projection 3 abuts against the lock ring 5. In addition to absorbing, the engagement between the projection 3 and the lock ring 5 prevents further withdrawal, and the insertion force of the insertion port 1 causes the insertion port 1 to contract or collapse due to the spacing member 8 contracting or crushing. The tip moves in the axial direction by a shrinkage allowance L ₂ that abuts against the inner end 2 of the receiving port ₂ , and further shrinkage is prevented by locking the tip and the inner end step ₂ b, and the ground Absorbs fluctuations and prevents joint damage.

In the propulsion method using this pipe joint structure, the pusher wheel 9 is movable in the axial direction with respect to the T-bolt 7, so that the propulsive force from the backward pipe P to the forward pipe P is It is transmitted to the previous pipe (preceding pipe) P through the insertion port 1, the flange 20, the spacing member 8, the push ring 9, the rubber ring 6 and the receiving port 2.
For this reason, if the propulsive force is large, the push ring 9 may be further pushed in, and the rubber ring 6 may have a pressure loss. Further, when the spacing member 8 contracts or collapses due to ground fluctuation such as an earthquake, there is a possibility that the push ring 9 is pushed in not a little and pressure loss of the rubber ring 6 occurs. This damage to the rubber ring 6 leads to deterioration of the water tightness of the joint part, which is a problem.

  As a means for preventing pressure loss of the rubber ring at the time of propulsion and when the insertion port 1 is pushed in, as shown in FIG. 10, a protective ring 4 is provided between the tip of the T bolt 7 and the spacing member 8 and the T bolt 7 is attached. The nut 4a is pressed against the end face of the receiving port 2 so that it cannot move in the axial direction, and the force from the spacing member 8 is transmitted to the preceding pipe P through the protective ring 4, the T bolt 7, and the receiving port 2, There is a technique that does not affect the rubber ring 6 (see Patent Document 1, paragraph 0030, FIG. 10).

  However, in this technique, the threading length of the T bolt 7 is standardized, and the nut 4a may not be screwed. That is, the standard T-bolt 7 must be newly threaded, which is complicated.

  Further, as shown in FIG. 11, the protection ring 4 has a U-shaped cross section, and the protection ring 4 is straddled between the spacing member 8 and the receiving end face 2a, and the push ring 9 is straddled. The end piece is applied to the end face of the spacing member 8 and the receiving end surface 2a, and the force from the spacing member 8 is transmitted to the preceding pipe P through the protective ring 4 and the receiving port 2 and is exerted on the rubber ring 6. There is a technique which does not exist (see Patent Document 1, paragraph 0030, FIG. 11).

  However, in this technique, the protective ring 4 protrudes outward (in the radial direction of the pipe P) from the push ring 9, and the roller of the flange 20 is used to prevent contact between the protective ring 4 and the sheath P '. 24 is projected further outward than the protective ring 4. If the protective ring 4 and the roller 24 protrude in this way, a gap with the inner surface of the sheath P 'is required, and if the sheath P' has a constant diameter, the diameter of the new tube P to be inserted therein. Becomes smaller. The new pipe P is preferably as large as possible in terms of transportation.

  An object of the present invention is to prevent pressure loss of the rubber ring 6 with a structure other than screwing the nut 4a into the T-bolt 7 without causing the protective ring 4 to protrude outward.

In order to achieve the above object, the present invention, like the U-shaped protective ring, transmits the propulsive force from the spacing member directly to the receiving end face and allows the transmission member to penetrate the push ring. It was.
In this way, if the propulsive force from the spacing member is transmitted directly to the receiving end face, there is no risk of pressure loss of the rubber ring due to the propulsive force and the pushing of the insertion port, and the water tightness of the rubber ring is improved. There will be no hindrance.
Further, if the transmission member penetrates the push wheel, it is not necessary to project the transmission member outside the push wheel 9.

  As a configuration of the present invention, a protrusion is provided on the outer peripheral surface of the distal end of the tube insertion opening, and a lock ring is provided on the inner surface of the tube reception opening. In the pipe joint structure of the two pipes in the propulsion method that newly installs the pipe line in the sheath pipe while being inserted into the joint, the insertion port is inserted into the receiving port via a rubber ring, and the tip of the insertion port is the inner surface of the receiving port When the insertion port is pulled out, the projection is locked to the lock ring to prevent further removal, and the insertion port is The required length from the point where the tip of the insertion port hits the back end step portion of the inner surface of the receiving port to the point where the projection is locked to the lock ring is movable, and the rubber ring is moved to the outer peripheral surface of the insertion port. It is pushed by the fitted push ring, and the bolt provided on the receiving end face penetrates the push ring. Then, a nut is screwed into the tip of the bolt, and when the nut is screwed in, the push ring approaches the receiving end surface and pushes the rubber ring, and a flange is provided on the outer periphery of the insertion port outside the receiving port. A spacing member is interposed between the press ring and the spacing member, and the tip of the insertion port is maintained at the middle of the required length by the spacing member, and the spacing member has a strength for transmitting a propulsive force. And the end face facing the push ring of the spacing member and the receiving end face that allow the insertion of the insertion opening into the receiving opening by contracting or crushing against a large compressive force such as an earthquake. In between, the structure which interposed the propulsive force transmission member which penetrates a push ring with a required space | interval over the perimeter in the meantime can be employ | adopted.

  The above-mentioned “a propulsive force transmission member penetrating the push ring is interposed between the end face of the spacing member facing the push ring and the receiving end face with a required interval all around the end face” means that each propulsion force is transmitted. Members are provided at equal intervals around the entire circumference, or a group of a plurality of equally spaced propulsion force transmitting members are equally spaced around the entire circumference as in the embodiments shown in FIGS. 3, 4, 7, and 8 to be described later. This refers to the intervention that was provided. The point is that the propulsive force is evenly transmitted to the entire circumference of the pipe by the propulsive force transmitting member.

  In this configuration, since the reaction force of the propulsive force and the pushing force is applied from the propulsive force transmitting member to the end face of the gap holding member facing the push ring, the gap holding member has the entire circumference of the end face as in the conventional case. It is preferable to apply a protective ring. For this reason, it is preferable that a propulsion force transmission member shall consist of the protection ring and the protruding member which penetrates a push ring from this protection ring, and contact | abuts to a receiving end surface.

  Further, the propulsive force transmission member and the spacing member slide on the outer peripheral surface of the insertion port in the circumferential direction, and the spacing is between the propulsion force transmission member and the spacing member or between the spacing member and the flange. If the holding material is designed to slide in the circumferential direction, the backward tube can rotate around its axis with respect to the preceding tube, which is effective for long-distance propulsion that may cause tube rolling. .

  In the present invention, as described above, the propulsive force from the spacing member is directly transmitted to the receiving end face by the member penetrating the push ring, so that the transmission member needs to protrude outward from the push ring. Nor. For this reason, it is not necessary to reduce the diameter of the new pipe inserted into the sheath by attaching this member.

An embodiment is shown in FIGS. 1 to 3, and this embodiment is a SII type joint structure of a ductile cast iron pipe P, and a projection 3 at the tip of the insertion port 1 and an inner surface of the receiving port 2 as in the prior art. A lock ring 5 is provided, and after inserting the insertion port 1 into the receiving port 2 through the rubber ring 6 and the backup ring 6a, the push ring 9 is applied to the rubber ring 6 and a T-bolt (clamping bolt). 7 is passed through the flange of the receiving end 2 end surface 2a and the push ring 9, and a nut 7a is screwed to the tip of the push ring 9 to fasten the rubber ring 6 to be sealed.
The pushing amount of the rubber ring 6 is adjusted by the screwing amount of the nut 7a. This push-in amount varies depending on the dimensional tolerance of the insertion port 1 and the receiving port 2 even for the pipes P having the same nominal diameter, and is appropriately set based on the tolerance.
The push ring 9 is formed with a long hole 10 extending in the circumferential direction over the entire circumference.

  An annular flange 20 is fitted on the outer periphery of the insertion port 1 outside the receiving port 2, and this flange 20 has an L-shaped cross-section and is divided into four equal parts or the like to form a saddle band. Fastening pieces 22 are provided at both ends of the piece 21, and ribs 23 are provided in the middle. A roller 24 is rotatably provided between the fastening pieces 22 and 22 of the adjacent divided pieces 21 and 21, and a bolt / nut 25 is inserted. By fastening the bolt / nut 25, a flange is provided. 20 is reduced in diameter and is pressed against the outer peripheral surface of the insertion port 1 (see paragraph 0027 of Patent Document 1).

A spacing member 8 is provided between the flange 20 and the push ring 9 and is a resin foam having a compressive stress of 1 to 30 kgf / cm ² (≈0.1 to 3 MPa) (more than 5 times that of a single resin). The elastic limit stress changes by changing the expansion coefficient) and the expansion ratio. Typical examples of these materials are polystyrene and polyurethane. The spacing member 8 has an annular shape, but may be divided in the circumferential direction, and may be intermittent. In short, it is sufficient to have strength against driving force.

A propulsive force transmitting member 30 is interposed between the end face 8a of the spacing member 8 facing the push ring 9 and the receiving end face 2a. As shown in FIGS. 2 and 3, the propulsive force transmission member 30 has a member 31 corresponding to the protective ring 4 applied over the entire circumference of the end surface 8 a of the spacing member 8. It consists of a projecting member 32 toward the receiving end face 2a at appropriate intervals around the periphery.
The size, projecting length, interval, etc. of each projecting member 32 may be appropriately determined in consideration of the size, interval, propulsive force transmission degree, etc. of the long hole 10 of the push ring 9, Each projecting member 32 is positioned symmetrically with respect to the center of the ring-shaped propulsion force transmitting member 30 so that force is uniformly applied from the projecting member 32 to the entire circumference of the receiving end surface 2a. preferable.

  Further, the propulsive force transmitting member 30 is also divided like the flange 20 and is formed into a ring shape by fastening both ends of the divided piece. The number of divisions is arbitrary. For example, as shown in FIG. 3, it is divided into two parts, as shown in FIG. Both members 31 and 32 may be integrally formed by casting, or the other member 32 may be joined to one member 31 by welding or the like.

The configuration of this embodiment is as described above. In the propulsion method shown in FIG. 9, the insertion port 1 of the pipe P is inserted into the receiving port 2 of the preceding pipe P in the same manner as in the prior art, and the SII joint Configure.
The flange 20, the spacing member 8, and the propulsive force transmission member 30 are fitted in the outer peripheral surface of the insertion port 1 in advance after the joint portion is configured (after assembly) or before the configuration. The shaped member 32 passes through the long hole 10 of the push ring 9 and comes into contact with the receiving end surface 2a.

In this state, the addition of thrust in the jack J, is inserted inserted port 1 to the position of the specified cylinder with dimension L ₂ of space holding member 8 comes into contact with the ring-shaped member 31 of the driving force transmitting member 30 in FIG. 2 It becomes a state shown, and is further propelled by the propulsive force of the jack J (see Patent Document 1, paragraphs 0028 to 0029 FIG. 7).
At this time, since the propulsive force transmitting member 30 resists the propulsive force and is kept constant, the distance between the push wheel 9 and the receiving end 2 end surface is kept constant. There is no effect.

  Further, in this propulsion, even if rolling occurs, the propulsive force transmitting member 30 and the spacing member 8 are not fixed to the outer peripheral surface of the insertion port 1, and the propulsive force transmitting member 30 and the spacing member 8 are not fixed. The gap holding member 8 slides in the circumferential direction between the gap holding member 8 and the flange 20, the pipe P and the preceding pipe P rotate relatively, and the pipe P is supported by one of the rollers 24. However, since it is possible to prevent the propulsive force from becoming excessive, it is effective for long-distance propulsion in which there is a concern about rolling. At this time, between the propulsive force transmission member 30, the spacing member 8 and the outer peripheral surface of the insertion port 1, between the propulsion member 30 and the spacing member 8, and between the spacing member 8 and the flange 20, A lubricant can be applied to the interface as appropriate (all or selectively). When the laying of the required length of the pipe P is completed, an air mortar or the like is placed between the sheath pipe P ′ and the new pipe P.

  The propulsive force transmitting member 30 may be any configuration as long as it passes through the push wheel 9 and transmits the propulsive force to the receiving end surface 2a without transmitting the propulsive force to the push wheel 9. For example, as shown in FIGS. Further, the projecting member 32 of the propulsive force transmitting member 30 may be constituted by a screw rod, and the screw rod 32 may be screwed into the ring-shaped member 31 and fastened and fixed by a nut 32a. In this case as well, it is divided in the same manner, and is formed into a ring shape by fastening both ends of the divided piece, for example, two divisions as shown in FIG. 7, four divisions as shown in FIG. Is also optional.

  The above embodiment is a case of the SII type joint. However, in the present invention, the rubber ring 6 such as the S type joint is pushed by the push ring 9 fitted to the outer peripheral surface of the insertion slot 1, and the push ring 9 The bolt 7 provided on the receiving end face penetrates, and a nut 7a is screwed into the tip of the bolt 7, and the push ring 9 approaches the receiving end face 2a and pushes the rubber ring 6 by the screwing of the nut 7a. Of course, it can be employed for various pipe joints.

Schematic perspective view of one embodiment XX sectional view of FIG. The perspective view of the propulsion force transmission member of the embodiment Perspective view of another example of propulsive force transmission member Schematic perspective view of another embodiment XX sectional view of FIG. The perspective view of the propulsion force transmission member of the embodiment Perspective view of another example of propulsive force transmission member Schematic of sheath tube propulsion method Cross section of the main part of the conventional example Cross-sectional view of the main part of another conventional example

Explanation of symbols

P 'sheath pipe (existing pipe)
P New tube 1 Insert 2 Receiving port 2a Receiving end surface 3 Protrusion 5 Lock ring 6 Water stop rubber ring 7 T bolt 8 Spacing retaining member 8a Spacing retaining member end surface 20 Flange 24 Roller 30 Propulsion transmitting member 31 Propulsion transmitting member 31 Ring-shaped member 32 Protruding member of propulsive force transmitting member

Claims (3)

A protrusion (3) is formed on the outer peripheral surface of the distal end of the insertion opening (1) of the tube (P), and a lock ring (5) is engaged with the inner surface of the receiving port (2) of the tube (P). In the propulsion method, the pipe (P) insertion port (1) is inserted into the receiving port (2) of the preceding pipe (P) and joined to the sheath pipe (P ′) with a new pipe line. In the pipe joint structure of the two pipes (P, P),
The insertion port (1) is inserted into the receiving port (2) with the rubber ring (6) interposed, and the tip of the insertion port (1) hits the back end step (2b) on the inner surface of the receiving port (2). When the insertion slot (1) is pulled out, the protrusion (3) is locked to the lock ring (5) and further slipping out is prevented. The opening (1) has a point that the protrusion (3) engages with the lock ring (5) from the point where the tip of the insertion opening (1) abuts the back end step (2b) of the inner surface of the receiving opening (2). The required length (L) is movable,
The rubber ring (6) is pushed by a push ring (9) fitted to the outer peripheral surface of the insertion opening (1), and a bolt (7) provided on the end face of the receiving opening (2) is attached to the push ring (9). A nut (7a) is screwed into the front end of the bolt (7), and the push ring (9) approaches the receiving end face (2a) by screwing the nut (7a). (6) Press
A flange (20) is provided on the outer peripheral surface of the insertion port (1) protruding from the receiving port (2), and a spacing member (8) is interposed between the flange (20) and the push ring (9). The tip of the insertion port (1) is positioned in the middle of the required length (L) by the spacing member (8),
The spacing member (8) has a strength to transmit a propulsive force, and contracts or collapses against a large compressive force such as an earthquake, and the insertion port (1) is inserted into the receiving port (2). Is acceptable,
Between the end face (8a) of the spacing member (8) facing the push ring (9) and the end face (2a) of the receiving port (2), the push ring has a necessary gap over the entire circumference between them. A pipe joint structure characterized in that a propulsive force transmitting member (30) penetrating (9) is interposed, and the propulsive force is not applied to the push wheel (9) by the propulsive force transmitting member (30).   A protective ring (31) applied over the entire circumference of the end surface (8a) facing the push ring (9) of the spacing member (8), and the protective ring (31). The pipe joint structure according to claim 1, characterized in that it comprises a projecting member (32) penetrating the push ring (9) from and in contact with the receiving end face (2a).   The propulsive force transmitting member (30) and the spacing member (8) slide on the outer peripheral surface of the insertion port (1) in the circumferential direction, and between the propulsive force transmitting member (30) and the spacing member (8). The pipe joint structure according to claim 1 or 2, wherein the spacing member (8) slides in the circumferential direction between the spacing member (8) and the flange (20). .

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