JP3470145B2 - Sheath tube type propulsion method and its thrust transmission device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-excavation propulsion method for burying fluid transportation pipes used for water supply, gas, sewerage, etc. underground, and a seismic resistant thrust transmission device suitable for use in this method. is there.

[0002]

2. Description of the Related Art As one construction method for burying a fluid transportation pipe such as a ductile cast iron pipe, there is a sheath pipe method. This method is a method of propelling a reinforced concrete pipe or a steel pipe as a sheath pipe, and inserting a ductile cast iron pipe or the like into the sheath pipe, and it is widely adopted because it does not require excavation.

A conventional pipe joint used in the sheath-type propulsion method is shown in FIG. 10, for example. This joint 100 is called a P II type joint,
The receiving port 101, the insertion port 102, the lock ring 103, the set bolt 104, the rubber ring 105, and the like.

FIG. 11 shows an outline of the above-mentioned conventional sheath-type propulsion method. In the existing pipe P'which is buried between the start pit S and the reaching pit R, a new pipe having a smaller diameter than this is installed. Tube P
Insert. A hydraulic jack J is installed at the start pit, the rear portion of the hydraulic jack abuts against the reaction force receiver H, and the front portion presses the new pipe P via the pushing angle B.
The new pipe P is sequentially joined by inserting the insertion opening 102 at the tip end thereof into the receiving opening 101 at the rear end portion of the preceding new pipe, and is pushed into the existing pipe. A leading sled K is attached to the front end of the new pipe.

The new pipes P, ... Are joined in the following manner. First, the lock ring 103 and the rubber ring 105
To the inside of the mouth. After that, the hydraulic jack J is operated, the insertion port 102 is inserted into the receiving port 101, and the set bolt is tightened. As a result, the succeeding new pipe is joined to the rear part of the preceding new pipe whose rear end faces the start pit. When the following new pipe is joined, press it with the hydraulic jack J,
A series of joined pipes is advanced toward the reaching pit.
The propulsive force of the hydraulic jack is
It is transmitted by contact with the end surface of the lock ring groove 107. In the figure, the new pipe is inserted into the existing pipe, but the method of inserting the new pipe by the pipe-in-pipe construction method into the sheath of the propulsion work is also performed.

Next, FIG. 12 shows an NS type joint which is slightly different from the above. This NS type joint has a socket 201, an insertion slot 202, a rubber ring 205, a lock ring 203, a lock ring centering rubber 204, It is composed of an insertion opening protrusion 208 and the like. When joining the NS type joint, the lock ring 203, the lock ring centering rubber 204 and the rubber ring 20 are joined.
5 is attached to the inner surface of the socket. After that, the hydraulic jack is operated to insert the insertion port 202 into the reception port 201. At the time of propulsion, the tip end of the insertion slot 202 has the rear end face 20 of the receiving slot 201.
The thrust is transmitted with the force up to 1a.

[0007]

In the case of the above-mentioned P II type joint, since the lock ring 103 and the end surface 107a of the lock ring groove 107 are in contact with each other as shown in the figure after the pipe-in is completed, The insertion opening 102 cannot move in the direction of entering the receiving opening 101. Therefore, there is a problem that the joint does not satisfy the performance as a seismic resistant pipe that needs to expand and contract in both directions. If a large pulling force acts on the joint due to an earthquake, etc., the lock ring 1
03 and the end surface on the opposite side of the lock ring groove 107 engage with each other to exert a separation preventing force. The S type ductile pipe, the S II type ductile pipe, and the NS type ductile pipe that are usually used as seismic resistant joints. Can withstand the pulling force of half the pipe.

Further, in the case of the NS type joint, when the propulsion is completed, the tip of the insertion slot 202 is in contact with the rear end face 201a of the receiving slot 201 as shown by the chain line in FIG. Therefore, when an earthquake occurs, it is possible to move in the pull-out direction and there is a margin for expansion, but it is not possible to move in the push-in direction. Therefore, N with the highest earthquake resistance performance
Even with S-type joints, since there is no expansion / contraction amount on the pushing side,
There is a problem that the performance as a seismic resistant tube cannot be fully exhibited.

As described above, none of the conventional ductile pipes for the propulsion method has the amount of expansion and contraction required for a seismic resistant joint, so that the joint portion is likely to be damaged by the occurrence of an earthquake. Therefore, an object of the present invention is to make it possible to embed a pipe in a state having a sufficient expansion / contraction amount as a seismic resistant joint.

[0010]

In order to solve the above problems, the present invention employs the following configurations. That is, the construction method according to the first aspect of the present invention is a sheath-tube-type propulsion construction method in which an insertion pipe connected to a pipe joint consisting of an insertion port and a receiving port is pushed into an existing sheath and the outer periphery of the insertion port is A thrust force transmitting member is provided that abuts the rear end of the receiving port to transmit the propulsive force and slips when a large pushing force is applied due to an earthquake to allow the insertion port to be pushed into the receiving port. The feature is that the tube is pushed in while transmitting the propulsive force of the insertion opening to the receiving opening via.

A thrust transmission device according to a second aspect of the present invention is a thrust transmission device attached to a pipe joint for connecting pipes by fitting the insertion port and the receiving port, A transmission member that is attached at a predetermined position and comes into contact with the rear end of the receiving port when propelling the pipe, and a transmission member that can transmit the propulsive force and is slippable when the pushing force due to an earthquake acts and is appropriate for the outer peripheral surface of the opening. It is characterized by including a fixing means for fixing with the strength of. If the transmission member is composed of a pair of semi-circular members, both of which are inserted, placed on the outer peripheral portion of the opening and fixed to each other by bolts, the installation at the construction site is easy.

Further, if the transmission member is provided with a sliding member (sledding) which projects in the radial direction of the pipe and is in sliding contact with the sheath pipe, the joint portion where the bending force acts most can be supported on the insertion pipe. Therefore, centering for supporting the insertion tube at the center of the sheath tube is easy, and it is not necessary to separately provide a centering member, which is preferable. If the sliding member is provided with a rotating roller that is swingable inward and outward and is biased in a direction projecting outward from the sliding member,
Since the roller rolls in contact with the inner surface of the sheath, it is possible to reduce resistance when the pipe is propelled.

According to the present invention, the propulsion force can be transmitted to the preceding pipe through the thrust transmission member during the propulsion when the pipe is inserted, so that the propulsion of the pipe can be efficiently performed. Also, after the completion of propulsion, the transmission member remains as it is, but when a large pushing force due to an earthquake acts, a slip occurs between the transmission member and the insertion opening, and the insertion opening moves in the insertion direction. Unreasonable force does not act on the pipe itself or the joint. Since the margin in the pull-out direction is the same as the conventional one, it is possible to obtain a buried pipe having excellent earthquake resistance.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described more specifically below based on the embodiments of the present invention shown in the drawings.

1 and 2 are partial cross-sectional views showing the structure of a pipe joint provided with a thrust transmission device according to the present invention.
The pipe joint 1 is an NS type joint that is usually used as a seismic joint for waterworks, and includes an insertion opening 2 and a receiving opening 3. The insertion port 2 is integrally formed with an insertion port protrusion 5 on the outer peripheral surface of the distal end portion of the ductile tube 4. If a large pulling force acts on the pipe joint due to an earthquake, etc.
The lock ring 17 described later is engaged with the lock ring 17 to prevent the insertion opening from coming out of the receiving opening. The insertion port projection 5 is provided in a ring shape on the entire outer peripheral portion of the insertion port 2.

The receiving port 3 is formed by expanding the diameter of the rear part of the ductile pipe 4 into a substantially funnel shape, and the groove 1 for mounting the rubber ring on the inner surface part thereof.
0 and a lock ring groove 12 are provided. An inward flange 13 is formed at the rear end of the receiving port 3, and the end surface thereof is formed as a flat surface 13a perpendicular to the axial direction. A rubber ring 15 for sealing is fitted in the groove 10, and a lock ring 17 which is expanded in one piece into the lock ring groove 12 is formed through a rubber ring 18 for centering the lock ring. Have been fitted.

The outer peripheral portion of the insertion opening 2 is in contact with the inward flange 13 of the reception opening 3 in a state where there is a predetermined pressing sill L between the tip of the insertion opening 2 and the rear end surface 3a of the reception opening 3. A thrust transmission device 20 that is in contact with and transmits the thrust is provided. The thrust transmission device 20 comprises a transmission member 25 and a fixing means for fixing the transmission member 25 to the outer peripheral surface of the insertion port 2, and as shown in FIG. 2, the semicircular members 25a, 25a are opposed to each other so that the bolts 26, 26 and the nuts. It is formed as a substantially annular body which is fastened and fixed by 26a. Overhanging pieces 25b, 25b are provided at both ends of the semicircular member 25a, and the bolts 26, 26 as fixing means are inserted into bolt holes provided in this portion. The transmission member 25 may have any shape as long as it is in close contact with and fixed to the outer peripheral surface of the insertion slot 2, and is most preferably a ring shape as shown in the figure.

A sled 30 having a polygonal shape in a side view is fixed to one end of the bolt 26 as a sliding member. As shown in FIG. 3, the sled 30 is formed as a hollow body that opens downward, and an arm 35 pivotally attached by a shaft 32 is provided in the hollow portion so as to be vertically rotatable. A roller 37 is rotatably supported at the tip of the arm 35, and an intermediate portion of the arm is directed downward by a pressing spring (coil spring) 39.
That is, the roller 37 is biased in the protruding direction.
The end face of the sled 30, which is a sliding member, is on the same plane as the end face of the front semicircular member 25a in the same direction, and in the state where the thrust transmission member 25 contacts the rear end face of the flange 13 of the receiver 3. The end surface of the sled also contacts the rear end surface of the flange 13. The material of each member of the thrust transmission device,
A metal material or the like having appropriate strength (for example, a steel material such as SS or FCD) can be used. Further, the roller (caster) may be one having an outer surface resin lining or rubber lining.

During the propulsion work of the pipe P provided with this thrust transmission member, the insertion port 2 and the receiving port 3 are provided as shown in FIG. 4 (a).
Then, the thrust transmission member 25 is inserted and attached to the outer peripheral portion of the opening 2 as shown in FIG. At this time, in a state in which a predetermined amount of pushing silo L (usually about 1% of the length of the pipe) remains between the distal end portion of the insertion opening 2 and the rear end surface 3a of the receiving opening 3,
The thrust transmission member 25 is attached so as to contact the rear end surface of the receiving port 3. In this case, all the work of joining the pipes and securing the amount of expansion and contraction of the pipes can be performed on the outer surface side of the pipes.
It can also be applied to small and medium diameter pipes with an aperture of less than 800 mm that cannot be put inside by an operator.

After joining the pipe P, the jack J is operated to push the pipe P into the sheath P '. At the time of this pushing, the thrust force applied to the rear end portion of the insertion slot 2 is transmitted to the preceding pipe through the thrust transmission member 25 and propelled. Therefore, the thrust transmission member 25 needs to be firmly inserted and fixed to the opening 2 so as not to slip due to this thrust. However, when a huge pushing force due to an earthquake acts, the insertion opening 2 must slip with respect to the transmission member 25, and therefore it is not preferable to fix the insertion member 2 by welding or the like.

While the insertion tube P is being pushed, since the rotating roller 37 of the sled 30 provided on the thrust transmission member 25 rolls on the inner surface of the sheath tube P'while supporting the insertion tube, the propulsion resistance is small. End Further, the roller 37 is a biasing spring 39.
In the direction of protruding from the sliding member 30, that is, FIG.
Since the insertion tube is biased downward, the coiled biasing spring 39 is bent by the weight of the insertion tube to hold the insertion tube near the center of the sheath tube. On the other hand, even if the roller 37 does not come into contact with the inner surface of the sheath by a large step or bend, the sled 30 makes contact with the inner surface of the sheath, so that there is no obstacle to the propulsion work.

Further, even if there is an obstacle such as a stone block S on the traveling path of the roller 37, it can be easily overcome by the sled 30 as shown in FIG. There is little risk of an increase in propulsion force or an unpromotable situation. Further, when the diameters of the sheath P'are different, as shown in FIGS. 7 (a) and 7 (b), the support bolt 2
By changing the length H (H ') of 6, it is possible to deal with it without exchanging other members, which makes it possible to reduce the number of parts and is economical.

In the state in which the propulsion of the pipe is completed, FIG.
As shown in FIG.
Is attached to the outer peripheral portion of the. On the other hand, when a large tensile force acts on the pipe joint due to an earthquake or the like, the pipe joint moves in the pull-out direction until the projection 5 of the insertion slot 2 contacts the lock ring 17, as shown in FIG. Therefore, it is possible to adapt to an external force in this direction. Furthermore, when a strong pushing force is applied due to an earthquake or the like, as shown in FIG.
A slip occurs between 5 and the insertion opening 2, and the insertion opening 2 is pushed into the receiving opening 3. At this time, the pushing margin is the distance L until the tip of the insertion slot 2 abuts on the rear end face 3a of the receiving slot 3, so that it can sufficiently cope with a normal earthquake. The thrust required to propel the pipe having a length of 30 m is about 0.5 t, and the pushing force due to the earthquake is much larger than this (for example, about 30 t). Instead, it is easy to determine the clamping force to slip due to an earthquake.

Next, FIGS. 8 and 9 exemplify an embodiment different from the above. In this embodiment, the sliding member (sledding) 30 'is formed as a plate, and the roller as described above is used. 37 is not provided. In this example, the sliding member 30 'always moves in contact with the inner surface of the sheath P'. In this way, the shape of the sliding member can be made appropriate. Although not shown, a sliding member is not provided,
It is also possible to provide the transmission member with only rollers that support the weight of the joint portion of the pipe and roll.

Further, FIGS. 13 and 14 exemplify the form of the transmission member different from the above. In the transmission member 125 shown in FIG. 13, one end of each of the semicircular members 126 and 126 divided into two has a pin 127. Is hinged on the other end, and the other end is fixed by a bolt 128 and a nut. With such a structure, the on-site installation is easier. Further, in the example shown in FIG. 14, a rubber lining 226 is applied to the inner surface of the transmission member 225. This has the advantage that slippage during transmission of thrust is unlikely to occur and scratches are less likely to occur on the insertion opening when slipping due to an earthquake or the like.

[0026]

As is apparent from the above description, according to the present invention, it is possible to transmit the propulsive force necessary for the insertion tube inserted into the sheath tube, and further, after the propulsion is completed, a large force due to an earthquake or the like is generated. When a pushing force is applied, a slip occurs between the thrust transmission member and the insertion opening, and the insertion opening is pushed into the receiving opening, so a sufficient amount of expansion and contraction is secured after burying, and excellent earthquake resistance. Has come to be obtained.

[Brief description of drawings]

FIG. 1 is a part (upper half) illustrating an embodiment of the present invention.
FIG. 4 is a front view of a pipe joint portion showing in section.

FIG. 2 is a left side view thereof.

FIG. 3 is a front view (a) and a side view (b) of a sliding member (sledding).

FIG. 4 is a partial cross-sectional front view (a) of a joint portion before joining and a front view (b) after joining with a thrust transmitting member attached.

FIG. 5 is an explanatory diagram when an obstacle is present.

FIG. 6 is a partial cross-sectional front view showing a joined state (a), an extended state (b) and a contracted state (c) of the joint portion.

FIG. 7 is an explanatory diagram when the diameters of the sheath tubes are different.

FIG. 8 is a partially sectional front view of an embodiment different from the above.

FIG. 9 is a side view of still another embodiment.

FIG. 10 is a sectional view of a conventional P II type joint.

FIG. 11 is an explanatory diagram of a pipe-in-pipe propulsion method.

FIG. 12 is a sectional view of a conventional NS type joint.

FIG. 13 is an explanatory view illustrating the structure of different transmission members.

FIG. 14 is an explanatory diagram showing still another example of the transmission member.

[Explanation of symbols]

1 Pipe fitting 2 outlet 3 mouthpiece 5 protrusions 7 flange 15 rubber ring 17 lock ring 18 Rubber ring for centering 20 Thrust transmission device 25 Thrust transmission member 30 Sliding member 37 Roller 39 spring

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhito Hanano 1-12-19 Kitahorie Nishi-ku, Osaka City, Osaka Prefecture Kurimoto Iron Works Co., Ltd. (56) Reference JP-A-11-218276 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16L 1/00 F16L 1/024 F16L 21/08

Claims (5)

(57) [Claims] 1. A sheath tube type propulsion method for pushing an insertion pipe connected to an existing sheath pipe by a pipe joint consisting of the insertion port and the receiving port, wherein a rear end portion of the receiving port is provided at an outer peripheral portion of the insertion port. A thrusting force transmitting member that abuts and transmits propulsive force and slips when a large pushing force due to an earthquake acts and allows pushing of the insertion port into the receiving port, and propels the insertion port through the thrust transmitting member A sheath-tube propulsion method characterized by pushing in the pipe while transmitting force to the receiving port. 2. A thrust transmission device attached to a pipe joint for connecting pipes by fitting the insertion port and the reception port, the thrust transmission device being mounted at a predetermined position on the outer peripheral surface of the insertion port, and receiving the port when propelling the pipe. A transmission member that comes into contact with the rear end portion of the rear end; and a fixing means that can transmit the propulsion force and that can be slipped when the pushing force due to an earthquake acts and that is fixed to the outer peripheral surface of the opening with appropriate strength. A thrust transmission device characterized by: 3. The transmission member comprises a pair of semicircular members,
The thrust transmission device according to claim 2, wherein the both are fixed to each other by a bolt so as to surround the insertion port. 4. The transmission member is provided with a sliding member that projects in the radial direction of the pipe and is in sliding contact with the sheath pipe.
Thrust transmission device described in. 5. The thrust transmission device according to claim 4, wherein the sliding member is provided with a rotating roller that is swingable inward and outward and biased so as to project outward from the sliding member.