JP2000080889A - Propulsion method and pipe joint for use therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-boring propulsion method for burying a fluid- transporting pipeline for use in city water, gas, sewage, etc., and a quake- resistant propulsion pipe joint suited for use therein. SOLUTION: In a pipe propulsion method, a rubber ring 18 for sealing a gap between the inner peripheral surface of a faucet 3 and the outer peripheral surface of a spigot 2 is provided as a pipe joint 1 therebetween, and a lock ring 17 on the inner peripheral surface of the faucet 3 and a spigot projection 5 engaging the lock ring 17 are provided so that when a large extracting force works on the joint 1 in an earthquake or the like, extraction of the spigot 2 from the faucet 3 is prevented. Further, a thrust-transmitting collar 25 that can be crushed after propulsion is finished is interposed between a flange 7 provided on the outer peripheral part of the spigot 2 and the end of the faucet 3 to secure a sufficient amount of expansion and contraction of the joint even after the propulsion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-cutting propulsion method for burying a fluid transport pipe used for water supply, gas, sewerage and the like underground, and a seismic pipe fitting suitable for use in the method. .

[0002]

2. Description of the Related Art There is a pipe-in-pipe method as one method of embedding a fluid transport pipe such as a ductile cast iron pipe. This method is a method of inserting a new pipe into an existing old pipe, and is widely used because it does not require digging.

[0003] A pipe joint in a conventionally employed pipe-in-pipe method is, for example, as shown in FIG. This joint 100 is called a PII type joint, and has a receiving port 101, an insertion port 102, a lock ring 103,
It is composed of a set bolt 104, a rubber ring 105 and the like.

FIG. 10 shows an outline of the above conventional pipe-in-pipe method, in which a new pipe P having a smaller diameter is installed in an existing pipe P ′ buried between a starting pit S and a reaching pit R.
Insert A hydraulic jack J is installed in the starting pit. The rear part of the hydraulic jack abuts against the reaction force receiver H, and the front part presses the new pipe P via the push angle B.
The new pipes P are sequentially joined by inserting the insertion port 102 at the front end thereof into the receptacle 101 at the rear end of the preceding new pipe, and are pushed into the existing pipe. A leading sled K is attached to the tip of the new tube at the head.

The joining of the new pipes P,... Is performed as follows. First, the lock ring 103 and the rubber ring 105
To the inside of the socket. Thereafter, the hydraulic jack J is operated, the insertion port 102 is inserted into the receiving port 101, and the set bolt is tightened. Thereby, the succeeding new pipe is joined to the rear part of the preceding new pipe whose rear end faces the starting pit. When the subsequent new pipe is joined, press with hydraulic jack J,
A series of joined rows of pipes are advanced toward the destination shaft.
The driving force of the hydraulic jack is determined by the lock ring 103,
It is transmitted by the contact with the end face of the lock ring groove 107. In the figure, a new pipe is inserted into the existing pipe. However, a method of inserting a new pipe into the pipe by the pipe-in-pipe method is also performed in the same manner.

Next, FIG. 11 shows a propulsion method using a UF type ductile tube slightly different from the above. The UF type ductile tube for the propulsion method includes a receiving port 201 and an insertion port 20.
2. It is composed of a rubber ring 205, a lock ring 203, a set bolt 204, a pressing ring 208, a bolt 209, a connecting rod 210, a mortar lining 206, an exterior concrete 211, and the like. When joining the UF type ductile pipe, first, the lock ring 203 is mounted in the lock ring groove 207 on the inner surface of the receiving port with the lock ring 203 expanded. Next, after inserting the insertion hole into the receiving port by the propulsion jack, the set bolt 204 is tightened, and the lock ring 203 is attached to the lock ring groove 207. Then, the rubber ring 205, the press ring 208, and the connecting rod 210 are attached from the inner surface side, and the bolt 2
Tighten at 09. Finally, mortar is filled into the bolt portion on the inner surface of the receiving port.

The UF type ductile pipe is pressed into the starting tunnel S by the propulsion jack J from the starting pit S as described above, or is propelled to the destination pit R while excavating by the leading conduit. The driving force at this time is transmitted through the engagement between the lock ring 203 and the lock ring groove 207.

[0008]

In the case of the PII type ductile pipe for the pipe-in-pipe method described above, after the pipe-in is completed, the lock ring 103 and the end face of the lock ring groove 107 are in contact with each other as shown in FIG. Has become
The insertion port 102 cannot move in a direction to enter the reception port 101. For this reason, there is a problem that the joint does not satisfy the performance as an earthquake-resistant tube that needs to expand and contract in both directions. If a large pulling force acts on the joint due to an earthquake or the like, the lock ring 103 and the lock ring groove 1
07 engages to exert a departure preventing force, and can withstand half the pull-out force of S-type ductile tubes, SII-type ductile tubes, and NS-type ductile tubes commonly used as seismic joints. .

In the case of the UF type ductile tube,
When the propulsion is completed, the lock ring 203 is in the lock ring groove 207. When an earthquake or the like occurs in this state and a pushing force or a pulling force acts on the joint, the joint part functions as a detachment prevention joint that is rigidly connected, and thus does not have a joint expansion / contraction amount necessary for the earthquake-resistant joint. Furthermore, since the joint is joined from the inner surface of the pipe, there is a problem that only a pipe having a nominal diameter of 700 mm or more, which is put into the pipe by an operator, can be joined. In addition, UF
The applicable diameter of the ductile tube is Φ700 to 2600 mm.

[0010] As described above, none of the conventional ductile pipes for the propulsion method has the necessary amount of expansion and contraction as a seismic joint, and therefore, there is a high possibility that the joint will be damaged by the occurrence of an earthquake. Therefore, an object of the present invention is to bury a pipe in a state having a sufficient amount of expansion and contraction as a seismic joint.

[0011]

In order to solve the above problems, the present invention employs the following configuration. That is, the propulsion method according to the present invention is a propulsion method for burying underground while connecting pipes, and a collar capable of transmitting propulsion force between an insertion port and a receiving port of the pipe and capable of crushing after burying. Interposed,
The propulsion force is transmitted to the preceding pipe via the collar, while the propulsion is performed, and after the propulsion is completed, the collar is crushed so that the insertion port and the reception port are connected to each other so as to be expandable and contractable.

Further, the pipe joint according to the present invention is a pipe joint for connecting a pipe by fitting an insertion port and a reception port, and seals a gap between an inner peripheral surface of the reception port and an outer peripheral surface of the insertion port. A rubber ring is provided, a lock ring is provided on the inner peripheral surface of the receiving port, and an insertion projection that engages with the lock ring to prevent the insertion port from deviating, and a flange provided on the outer peripheral portion of the insertion port and a receiving end are further provided. A collar for transmitting a propulsive force that can be crushed after the propulsion is completed is interposed between the propulsion unit and the propulsion unit.

As the collar for transmitting the propulsion force, for example, a lime-based material containing calcium oxide (CaO) as a main component, which expands by hydration in a concrete annular body, or 3CaO.3Al ₂ O _3. CaSO ₄ , C
It is conceivable to bury a static crushing agent containing a calcium-sulfo-aluminate (CSA) compound containing aSO ₄ and CaO as main components.

According to the present invention, the propulsion force can be transmitted to the preceding pipe through the collar for transmitting the propulsion force during the propulsion work, so that the propulsion of the pipe can be effectively performed. Also, after the propulsion is completed, by crushing the collar for transmitting the propulsion force, it becomes possible to expand and contract by the amount of the collar in the fitting portion between the insertion port and the receiving port,
It has a function as an earthquake-resistant joint.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically based on embodiments of the present invention shown in the drawings.

FIG. 1 is a sectional view showing the structure of a pipe joint according to the present invention. This pipe joint 1 is an NS type joint usually used as a seismic joint for water supply. Mouth 3 The insertion port 2 has an insertion port projection 5 integrally provided on the outer peripheral surface of the distal end portion of the ductile tube 4. When a large pull-out force acts on the pipe joint due to an earthquake or the like, the insertion port projection 5 and a lock ring 17 described later engage with each other to prevent the insertion port from coming out of the receiving port. The insertion port projection 5 is provided in a ring shape over the entire outer peripheral portion of the insertion port 2. A flange 7 is integrally provided at a position on the rear side of the insertion port 2. 8, ...
These are backup ribs provided at appropriate intervals on the back surface of the flange 7. These flange 7 and reinforcing rib 8
Is made of metal and fixed on the outer peripheral surface of the insertion port 2 by welding or the like.

The receiving port 3 is formed by enlarging the rear portion of the ductile tube 4 in a substantially funnel shape, and has a groove 1 for mounting a rubber ring on the inner surface thereof.
0 and a lock ring groove 12 are provided. An inward flange 13 is formed at the rear end of the socket 3, and the end face thereof is formed as a plane 13 a 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 and singly formed in the lock ring groove 12, is inserted through a rubber ring 18 for centering the lock ring. It is fitted. 19 is an interior material and 20 is an exterior concrete.

A thrust transmitting collar 25 is interposed between the flange 7 of the insertion port 2 and the inward flange 13 of the receiving port 3. The propulsion force transmitting collar 25 is formed as an annular integral body as shown in FIG. 2, and is made of a material having appropriate brittleness and rigidity, such as concrete and ceramics. The collar 25 has an appropriate space (L) at its middle part in the thickness direction along the circumferential direction.
, An insertion hole 26 penetrating back and forth is formed, and the insertion hole is filled with a static crushing agent 27. The relationship between the diameter d of the insertion hole and the hole interval L is preferably, for example, about L = 8d.

The static crushing agent 27 is capable of crushing the collar after the propulsion is completed. This non-explosive demolition agents, and those of the lime mainly composed of calcium oxide _{(CaO), 3CaO · 3Al 2} O 3 · CaSO 4, Ca
There are two types: calcium-sulfo-aluminate (CSA) based on SO ₄ and CaO. Lime-based CaO undergoes a hydration reaction to produce fine colloidal calcium hydroxide Ca (OH) ₂ . This Ca (OH) ₂ grows into a long and anisotropic hexagonal plate-like crystal with the passage of time. This causes the crystal pressure to press against, and an inflation pressure to the constraint wall is generated.
Also, in the case of the CSA type, since it grows into needle-like crystals called ettringite by a general hydration reaction as shown below, an expansion pressure to the constraining wall is generated similarly to the lime type. . These inflation pressures act on the filling holes,
By generating a compressive stress in the periphery around the hole,
Tensile stress is generated in a direction perpendicular to this.

[0020]

Embedded image

A crack is generated when the tensile stress exceeds the tensile strength of the driving force transmitting collar, and furthermore, the expansion of the static crushing agent causes the propagation of the crack. For this reason, a large number of cracks are formed in the circumferential direction and the axial direction of the driving force transmitting collar, and crushing is performed. As described above, since the two types of main components, both of the lime type and the CSA type, have the effect of crushing the propulsion transmitting collar, either of the components may be used. Further, components other than these two types may be used as long as the object of the present invention is achieved. In the case of the pipe-in-pipe method, debris due to this crushing falls off in this gap because there is a gap between the sheath pipe (outer pipe) and the propulsion pipe (inner pipe), and the insertion port 2 and the receiving port 3 Is removed from between. For this reason, the joint can be contracted by an amount separated by the collar 25. In the case of the propulsion method, the compression strength of the propulsion force transmitting collar 25 is close to zero, so that the joint can be contracted by that much.

The hydration reaction for crushing the collar for transmitting the propulsion force is performed, for example, by stirring the static crushing agent and water before the propulsion work and filling the static crushing agent into the static crushing agent insertion hole, without reacting with water. After the propulsion, it can be realized by a method of reacting with moisture contained in the soil of the ground around the pipe. When urgently required, water may be injected into this portion with a pipe or the like. The static crushing agent is a component similar to the swelling agent generally used for expanded concrete, and promotes crushing of concrete or the like by containing the swelling agent in excess. In addition, this static crushing agent is generally used for crushing rocks and concrete accompanying construction work, and can crush concrete and the like without generating vibration, noise, stepping stones, etc. Moreover, since it does not contain harmful components, no adverse effect on the tubular body is expected.

The insertion shape of the static crushing agent may be any shape other than that shown in the drawings as long as the purpose of crushing the propulsion transmitting collar and securing the expansion and contraction amount of the joint can be achieved. . Also, as shown in the illustrated example, the color 2
The method is not limited to the method in which the static crushing agent is filled in the hole drilled in 5,
The collar itself may be made of concrete containing a static crushing agent as an admixture. In this case as well, after completion of the propulsion, a reaction can be caused by water contained in the soil around the pipe, and the pipe can be crushed by a method of securing the joint expansion and contraction amount.

The method of installing the joint 1 will be described below. First, as shown in FIG. 3A, a propulsion force transmitting collar 25 is deposited on the outer peripheral portion of the insertion port 2. On the other hand, the rubber ring 15 and the lock ring 17 are attached to predetermined positions of the receiving port 3, and the insertion port 2 is inserted into the receiving port 3. Thereafter, the pipe whose insertion port 2 is inserted into the receiving port 3 is sequentially inserted into the sheath by the hydraulic jack in the case of the pipe-in-pipe method, and sequentially inserted while excavating by the leading pipe in the case of the propulsion method. . In the state shown in FIG. 3B, the collar 25 is clamped between the flange 7 of the insertion port 2 and the inward flange 13 of the receptacle 3, and the propulsive force of the hydraulic jack is reduced by the propulsive force transmitting collar 25. To the preceding tube.

Since the static crushing agent is set so as to expand after the end of propulsion and crush the propulsion transmitting collar 25, the expansion causes the collar 25 to crack as shown in FIG. 3 (c). As a result, the compressive strength of the collar becomes substantially zero, and the amount of expansion and contraction of the joint is ensured by the front and rear width of the collar. When a pipe is inserted into a sheath, the cracked propulsion force transmission collar falls off as a fragment because there is a gap between the sheath and the inner peripheral surface of the inserted pipe as described above. . FIG. 3D shows a state in which the propulsion force transmission collar has fallen and the pushing amount L1 ′ of the joint has been secured.

FIG. 4 shows the amount of expansion and contraction of the joint of the present invention. There is a margin of L1 or L1 'in the direction in which the joint 1 is pushed in, and there is a margin of L2 in the direction in which the joint 1 is pulled out. When a pull-out force acts on the joint, the lock ring 17 engages with the projection 5 to prevent the joint from falling off. These relationships are
L1 ′ ≧ L1 = L2. Therefore, for example, it is also easy to secure a specified pushing allowance of 1% of the pipe length and a drawing allowance of 1% of the pipe length.

Next, FIG. 5 shows an embodiment different from the above. In this embodiment, the propulsion force transmitting collar 25 is formed at the same time when the pipe is manufactured. Since the outer surface of the ductile cast iron tube is not smooth, in this case, there is a possibility that the concrete collar is less likely to come off from the outer surface of the tube. Therefore, it is preferable to apply a smoothing agent 28 such as a resin paint on the outer surface of the pipe on which the collar is to be mounted in advance, and then drive concrete in the color on the smoothing agent 28. Thereby, the outer surface of the tube is smoothed, and the fragments easily come off from the outer surface of the tube when the collar is crushed, so that the joint expansion and contraction amount is secured. As the resin paint,
For example, an epoxy resin, a polyurethane resin, a fluororesin, or the like can be used.

FIG. 6 shows a further different embodiment. In this joint, a lock ring 37 is fitted in a lock ring groove 32 provided on the rear end side of the receiving port with respect to the rubber ring 15. An insertion projection 35 with which this engages is formed at an intermediate portion between the lock ring and the rubber ring. The lock ring 37 is fixed by a set bolt 38.
The rubber ring 15 is fitted in the rubber ring groove 30. Other parts are substantially the same as those in the embodiment of FIG.

In this embodiment, since the rubber ring 15 is disposed on the back side of the lock ring 37, when the propulsion force transmitting collar 25 is crushed, the fragments are less likely to enter the sliding contact portion of the rubber ring, so that the sealing is not performed. Sex is not impaired.

FIG. 7 shows still another embodiment. In this joint, a mixing prevention ring 40 is interposed between the end face of the receiving port 3 and the driving force transmitting collar 25. The mixing preventing ring 40 prevents the fragments from entering the receiving port when the driving force transmitting collar 25 is crushed. The mixing prevention ring 40 is preferably made of a material that makes it difficult for fragments of the propulsion transmission collar to enter the interior of the receiving port. For example, a rubber ring or a resin ring is suitable.

FIG. 8 shows different forms of the static crushing agent inserted into the propulsion transmitting collar. In this embodiment, the static crushing agent 27 is obliquely inserted between the outer peripheral surface side and the inner peripheral surface side of the thick portion of the propulsion transmitting collar. For this reason, the crushed concrete fragments will surely fall off, and the joint expansion and contraction amount can be more reliably secured.

In the above-described embodiment, the driving force transmitting collar is crushed by a static crushing agent. However, the driving force transmitting collar can transmit a sufficient driving force during propulsion. After the propulsion is completed, any material can be used as long as it can be crushed to secure the amount of expansion and contraction of the joint. It should be provided. For example, a method is also conceivable in which a gas pipe (air hose or the like) is arranged to the position of the propulsion force transmitting collar, and after the propulsion is completed, the collar is blown off with a compressed gas (air) or the like.

[0033]

As is apparent from the above description, according to the present invention, the propulsion force can be transmitted to the pipe joint used in the propulsion method, and the propulsion is crushed and removed from the joint after the propulsion is completed. Since the collar for force transmission was interposed, sufficient expansion and contraction was secured after burial, making it extremely effective as a seismic joint.

[Brief description of the drawings]

FIG. 1 is a sectional view of a pipe joint according to the present invention.

FIG. 2 is a sectional view (a) and a front view (b) of the driving force transmitting collar.

FIG. 3 is an explanatory view of a joint joining method.

FIG. 4 is a sectional view of the joint after the collar is crushed.

FIG. 5 is a sectional view of a joint showing a different embodiment.

FIG. 6 is a cross-sectional view of a joint showing still another embodiment.

FIG. 7 is a cross-sectional view of a joint showing a further different embodiment.

FIG. 8 is a sectional view (a) and a front view (b) of a collar different from the above.

FIG. 9 is a sectional view of a conventional PII type pipe joint.

FIG. 10 is an explanatory diagram of a propulsion method.

FIG. 11 is a sectional view of a conventional UF type pipe joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe joint 2 Insertion port 3 Reception port 5 Projection 7 Flange 17 Lock ring 18 Rubber ring 25 Propulsion transmission collar 27 Static crushing agent

Claims (4)

[Claims] 1. A propulsion method for burying underground while connecting pipes, wherein a collar capable of transmitting propulsion force between the insertion port and the receiving port of the pipe and capable of being crushed after burying is interposed. A propulsion method in which propulsion is transmitted while transmitting propulsion force to a preceding pipe via a collar, and after completion of the propulsion, the collar is crushed so that an insertion port and a reception port are connected to each other so as to be extendable. 2. A fitting for connecting a pipe by fitting an insertion port and a receiving port, wherein a rubber ring for sealing a gap between the inner peripheral surface of the receiving port and the outer peripheral surface of the insertion port is provided. A lock ring and an insertion projection that is engaged with the lock ring to prevent the insertion opening from being displaced are provided on the inner peripheral surface of the mouth, and furthermore, a propulsion is provided between the flange provided on the outer periphery of the insertion opening and the receiving end. A pipe joint having a collar for transmitting propulsion force that can be crushed after completion. 3. A lime based color containing calcium oxide (CaO) as a main component, or 3CaO.3Al ₂ O _3.
The pipe joint according to claim 2, wherein the pipe joint is formed of a brittle material containing CaSO ₄ , a calcium-sulfo-aluminate-based (CSA-based) compound containing CaSO ₄ and CaO as main components. 4. The collar is a concrete annular body.
Formed, with calcium oxide (CaO) mainly in place
Lime-based or 3CaO.3Al _Two O_Three ・ C
aSO_Four , CaSO_Four And CaO as the main component
Csium sulfo aluminate (CSA) compounds
2. A static crushing agent containing embedded therein, etc. is embedded.
Or the pipe joint according to 2.