JP2002039460A - Sealing construction method and sealing equipment for existing pipe joint part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability in sealing by forming an uniform sealing layer on a joint part. SOLUTION: A filler hole 15 of a sealing material is formed on an upper part of the joint part 12 of existing pipes 1 and 2, and a permanent magnet 40 is placed over the existing pipes 1 and 2. The existing pipes 1 and 2 are magnetized to form a magnetic path 22 from the existing pipe 1 to the existing pipe 2 across the joint part 12. In this condition, the sealing material mixed with a magnetic member is injected to the joint part 12 from a pipe 33 of an injection device 20. As the mixed magnetic member receives the attraction force from a magnetized tubular body, the sealing material 50 is also attracted to a tubular body side with the magnetic member. As a result, the sealing material injected to the upper part can be prevented from excessively flowing to a lower part, and the approximately uniform seal layer is formed over an inner periphery of the joint part 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a facility for sealing joints in existing gas pipes and water pipes buried underground.

[0002]

2. Description of the Related Art Gas pipes and water pipes buried underground need to be sealed to prevent leakage at joints of pipes. For this reason, various sealing methods have been conventionally proposed. For example, the outer periphery of the joint portion of the existing pipe is surrounded by a heat-shrinkable cover with a fastener, and a sealing material is interposed between the heat-shrinkable cover and the joint portion. A method of melting the joint to seal the joint is actually employed on site.

However, in the above-mentioned construction method, since the outer circumference of the existing pipe is covered with the heat shrinkable cover, it is necessary to excavate the ground deeply until the pipe buried in the ground is completely exposed. For this reason, there is a drawback that excavation work requires time and cannot be performed in case of urgent repair work.

Therefore, instead of the above-described method, a method is also used in which an injection hole is formed by externally piercing a joint portion of an existing pipe, and a sealing material is injected into the joint portion from the injection hole. According to this method, it is possible to excavate the ground until the upper surface of the pipe is exposed, and to inject the sealing material only by piercing the exposed joint portion. Can be shortened, and it is possible to respond even in case of emergency construction.

FIG. 9 shows an example of such a construction method. In the drawing, 1 is an existing gas pipe, 2 is an existing gas pipe connected to the gas pipe 1, and these are buried in the soil. Reference numeral 3 denotes a connecting portion for connecting the gas pipe 1 and the gas pipe 2, which comprises a bolt 6 inserted into the flange 4 of the gas pipe 1, a nut 7 fastened to the bolt 6, and a pressing wheel 5. I have. 8 and 10 are yarns made of a fibrous natural material, 9 is cement, and 11 is packing rubber. The yarns 8 and 10, the cement 9, and the packing rubber 11 are loaded by being pushed between the inner peripheral surface of the gas pipe 1 and the outer peripheral surface of the gas pipe 2 by the pressing ring 5.

Reference numeral 12 denotes a joint between the gas pipes 1 and 2, reference numeral 15 denotes a sealing material injection hole formed in the gas pipe 1 by a perforation device (not shown), and reference numeral 33 denotes a pipe for injecting the sealing material.
The injection hole 15 is formed at a position directly above the yarn 8, and the sealing material injected from the pipe 33 is impregnated into the yarn 8 and also flows into the joint portion 12, and hardens the joint portion 12. Seal over the inner circumference.

[0007]

However, in the method of FIG. 9, as shown in the cross-sectional view of FIG.
The sealing material 50 that has flowed into the tube 2 flows down to the lower part of the tube due to gravity, and the seal layer tends to become thicker as it goes down the tube. For this reason, there is a problem that the thickness of the sealing layer becomes uneven, and a sufficient sealing effect cannot be obtained in the upper part of the tubular body having a thin sealing layer.

The present invention has been made to solve the above problems, and has as its object to improve the reliability of a seal by forming a uniform seal layer on a joint portion.

[0009]

In order to solve the above-mentioned problems, a sealing method according to the present invention uses a sealing material mixed with a magnetic material as a sealing material, and applies the sealing material in a state where an existing pipe is magnetized. The injection is performed from the injection hole. As the magnetic material, for example, triiron tetroxide (Fe
₃ O ₄ ) powder can be used, and, for example, a two-component reaction-curable urethane-modified epoxy resin can be used as the sealing material.

In this manner, the magnetic material mixed in the sealing material receives an attractive force from the magnetized tube, and by this action, the sealing material injected into the joint portion is removed together with the magnetic material. It is drawn to the pipe body side, and the adhesive state with the pipe body is maintained even at the upper part of the existing pipe. For this reason,
Excessive downward flow of the sealing material injected from above is suppressed, and the thickness of the sealing layer is secured above the joint. As a result, a seal layer having a substantially uniform thickness can be formed over the inner periphery of the tube, and the reliability of the seal can be improved.

In order to magnetize the existing pipe, a magnetizing means such as a permanent magnet or an electromagnet is disposed above the existing pipe. In this case, it is preferable to arrange the magnetizing means over both existing pipes so that a magnetic path is formed from one existing pipe across the joint portion to the other existing pipe.

Further, the sealing equipment according to the present invention is provided with an injection device for injecting a sealing material mixed with a magnetic material, and the above-described magnetizing means. The injection device and the magnetizing means can also be integrated. According to this, since the injection device and the magnetizing means can be provided at the same time, workability is improved. Further, the magnetizing means can be used as a means for fixing the injection device to an existing pipe.

[0013] Further, in a sealing facility using an electromagnet as the magnetizing means, it is preferable to provide a control means for controlling energization of the coil of the electromagnet. The control means includes, for example, a variable resistor and a control unit. According to this, since the magnetic flux density of the magnetic path changes by controlling the current of the coil, the magnetic force at the joint can be adjusted to an optimum value.

When a control unit is provided as the control means, the control unit can control not only the current of the coil but also the injection of the sealing material. According to this, the injection operation of the sealing material can be automated.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. 1 to 4 show an example of a sealing method according to the present invention, and FIG. 1 is a view showing a state in which an injection hole for a sealing material is drilled at an upper part of a joint part of an existing pipe. In FIG. 1, reference numeral 1 denotes an existing pipe such as a gas pipe, and 2 denotes an existing pipe connected to the existing pipe 1, which are buried in the soil. A connecting portion 3 connects the existing pipe 1 and the existing pipe 2 and includes a bolt 6 inserted into the flange 4 of the existing pipe 1, a nut 7 fastened to the bolt 6, and a pressing wheel 5. I have. 8 and 10 are yarns made of a fibrous natural material, 9 is cement, and 11 is packing rubber. The yarns 8 and 10, the cement 9 and the packing rubber 11 are connected to the inner peripheral surface of the existing pipe 1 and the existing pipe 2 by the pressing ring 5.
Is loaded by being pushed between the outer peripheral surface of the main body. The above configuration is the same as that shown in FIG.

Next, the procedure of the sealing method according to the present invention will be described. First, after excavating the ground until the upper surfaces of the existing pipes 1 and 2 are exposed, as shown in FIG.
An injection hole 15 for the sealing material is pierced in the upper part of the second member 2 by a piercing device 13 such as a drill. Reference numeral 14 denotes a rotary blade provided at the tip of the punching device 13. Perforated injection hole 15
Communicates with the joint 12.

Subsequently, the sealing equipment shown in FIG. 2 is provided. The sealing equipment includes an injection device 20 for injecting a sealing material, and a permanent magnet 40 as a magnetizing means. In the injection device 20, 21 is a fixed lever, 22 is a movable lever, 23 is a support shaft of the movable lever 22, 24 is a rack that converts the rotation of the movable lever 22 into linear motion, 25 and 2
6 is a pair of plungers that move up and down with the rack 24,
27 is a connecting member for connecting the rack 24 and the plungers 25 and 26; 28 and 29 are cartridges storing a main agent and a hardening agent of a sealing material, respectively; 30 is a frame supporting the cartridges 28 and 29; , 29, a Y-shaped tube for supplying a hardening agent, 32 is a static mixer for mixing the main agent and a hardening agent supplied from the Y-shaped tube 31, and 33 is a joint sealing material for the joint portion 12 It is a pipe to guide to.

On the other hand, in the permanent magnet 40, 41 is a magnetic pole constituting an N pole, 42 is a magnetic pole constituting an S pole, and 43 is a U-shaped connecting portion made of a magnetic material connecting these magnetic poles 41 and 42. . Since the magnetic pole 41 and the magnetic pole 42 are in contact with the upper surfaces of the existing pipes 1 and 2, respectively, and are connected by the connecting portion 43, the permanent magnet 40 is disposed across the existing pipes 1 and 2. Become. As a result, the existing pipes 1 and 2 made of a magnetic material such as iron are magnetized by the permanent magnet 40, and a magnetic path 44 extending from the existing pipe 1 across the joint 12 to the existing pipe 2 is formed.

As described above, the existing pipes 1 and 2 are
In the state magnetized by the above, a sealing material is injected from the injection device 20 into the joint portion 12 through the injection hole 15. That is, when the fixed lever 21 and the movable lever 22 are gripped by hand and the movable lever 22 is rotated in the direction of arrow A in FIG. 2 around the support shaft 23, the rack 24 is lowered in the direction of arrow B. Along with this, the plungers 25 and 26 connected to the rack 24 by the connecting member 27 also descend in the arrow B direction. The lower ends of the plungers 25 and 26 are
A piston (not shown) is attached to the inside of each of the cartridges 8 and 29, and the seal material in the cartridges 28 and 29 is sent out to the Y-tube 31 by the movement of the piston.

The sealing material used herein is of a two-component reaction-curing type in which a base material and a curing agent are mixed, and for example, a urethane-modified epoxy resin is used. Then, a magnetic material is mixed in the base material or the curing agent of the sealing material. As the magnetic substance, for example, a powder of triiron tetroxide (Fe ₃ O ₄ ) can be used. The main agent and the curing agent sent to the Y-shaped tube 31 are mixed in the static mixer 32. The static mixer 32 contains a mixing element therein, and the main agent and the curing agent are mixed while passing through the mixing element.

The mixed sealing material is sent out to a pipe 33. The tip of the pipe 33 is inserted into the injection hole 15, and the sealing material is guided from the pipe 33 to the joint portion 12, and a part of the sealing material is impregnated in the yarn 8. FIG.
Is an enlarged view of the vicinity of the injection hole 15 and shows a state where the sealing material 50 is injected from the pipe 33.

When the sealing material 50 mixed with a magnetic material is injected into the joint 12 in a state where the existing pipes 1 and 2 are magnetized by the permanent magnet 40 in this manner, the gap of the joint 12 is filled with the magnetic material. , From magnetic pole 41 (N pole) to magnetic pole 4
Lines of magnetic force reaching 2 (S pole) are concentrated in the gap portion of the joint portion 12, and in this portion, the magnetic material mixed in the seal material 50 receives an attractive force from the magnetized tube. By this action, the sealing material 50 is also drawn toward the tube together with the magnetic material, and maintains the state of adhesion with the tube.
Even if the seal material 50 is directly injected into the joint portion 12 by forming the seal member 50 directly above the joint portion 12, it is possible to suppress the injected seal material 50 from excessively flowing downward.

As a result, as shown in FIG. 5A, the sealing material 50 flows down along the joint portion 12 while maintaining the thickness of the seal layer at the upper portion of the joint portion 12, and as shown in FIG.
As shown in (b), the inner circumference of the joint portion 12 is evenly distributed. For this reason, a thick portion and a thin portion of the seal layer do not occur as in the related art, and a uniform seal layer is formed.

When the sealing material 50 is cured and the sealing is completed, the pipe 33 is removed from the injection hole 15 and the injection hole 15 is sealed with a plug 51 such as a screw as shown in FIG. Then, the injection device 20 and the permanent magnet 40 are removed, and the soil is buried in the exposed existing pipes 1 and 2, thereby completing a series of operations.

If the viscosity of the sealing material 50 is too low,
Even if the suction force acts on the mixed magnetic material, only the resin flows down. Conversely, if the viscosity is too high, the flow down is insufficient and the sealing performance of the lower part of the tube is impaired. Also, if the curing time of the sealing material 50 is too short, the sealing material does not cover the entire periphery of the joint portion 12, and if the curing time is too long,
It takes time to remove the permanent magnet 40, and the operation is delayed. Therefore, it is necessary to appropriately select the viscosity and the curing time of the sealing material 50.

When the existing pipe is a gas pipe, the properties required for the sealing material used include, for example, the following. (1) Form a film even in raw gas shielded from air and moisture. (2) Small volume shrinkage after curing. (3) Excellent chemical resistance. (4) Flexible film after curing. (5) Excellent adhesion to gas pipes (iron pipes) (6) Relatively low viscosity and easy to reach gaps in joints

There are various types of such sealing materials. When the curing time is to be shortened (for example, about several minutes to 1 hour), a two-component reaction curing type is used, and when the curing time is extended ( For example, about one to three hours), a one-component type is used. As the two-component reaction curing type sealing material, in addition to the urethane-modified epoxy resin mentioned above, various types of epoxy resin, urethane resin, epoxy-modified urethane resin, urea-modified urethane resin, polysulfide resin, silicone, modified silicone, etc. Resin can be used. Further, as the one-component sealing material, acrylic rubber, acrylic resin, SBR, or the like can be used in the emulsion type, and chlorosulfonated polyethylene, acrylic, butyl rubber, or the like can be used in the solvent type.

On the other hand, as the magnetic substance mixed in the sealing material, in addition to the above-mentioned triiron tetroxide (Fe ₃ O ₄ ), diiron trioxide (Fe ₂ O ₃ ) and iron oxide (FeO) are used. Alternatively, a powder of iron, nickel, a nickel compound, cobalt, or the like may be used.

The mixing ratio of the sealing material and the magnetic substance powder is selected to be about 0.5 to 3: 1. For example, as a typical mixing, in the case of a urethane modified epoxy resin and triiron tetroxide,
1 to 1.5: 1. The viscosity of the mixture of the sealing material and the magnetic powder is approximately 2000 to 10000 mPa.
It is preferably in the range of s.

According to an experiment, a sealing material having a mixing ratio of urethane-modified epoxy resin and triiron tetroxide powder of 1 to 1.5: 1 and a viscosity of 3000 mPa · s was used. At 320 Tesla, adsorption power is 64
As a result of using the rare earth magnet of 00 g, it was confirmed that a film of the sealing material having a substantially uniform thickness was formed over the inner periphery of the joint portion.

FIG. 6 shows another embodiment of the sealing equipment.
An electromagnet 60 is used in place of the permanent magnet 40 shown in FIG. The electromagnet 60 includes an iron core 63 having magnetic poles 61 and 62 at both ends, and a coil 64 wound around the iron core 63. Reference numeral 65 denotes a power supply for energizing the coil 64, 66 denotes a power switch, and 67 denotes a variable resistor as control means for controlling a current flowing through the coil 64. Other configurations are the same as those in FIG.

Also in FIG. 6, since the magnetic poles 61 and 62 and the iron core 63 are arranged over the existing pipes 1 and 2,
When the power switch 66 is turned on and the coil 64 is energized,
A magnetic flux is generated in the coil 64, and the existing pipes 1 and 2 made of a magnetic material are magnetized, and a magnetic path 44 extending from the existing pipe 1 to the existing pipe 2 across the joint 12 as in FIG. .
In this case, by controlling the current of the coil 64 by the variable resistor 67, the magnetic flux density in the magnetic path 44 changes, so that the joint portion is changed according to the viscosity of the sealing material, the mixing ratio of the magnetic material, the diameter of the existing pipe, and the like. 12 can be adjusted to an optimum value.

FIG. 7 shows another embodiment of the sealing equipment.
An electric mechanism including a motor 70, a speed reducer 71, a feed screw 72, and a nut 73 is used instead of the manual operation mechanism including the levers 21 and 22 and the rack 24 in the injection device 20 of FIG. This electric mechanism is a cartridge 2
8 and 29 are mounted on a frame 30. The frame 30 is attached to an electromagnet core 63 and an insulating member 68.
Has been fixed through. For other configurations, see FIG.
Is the same as When the motor 70 is energized, the feed screw 72 rotates via the speed reducer 71, and the connecting member 27 fixed to the nut 73 descends in the direction B. As described above, the cartridge 2 is moved by the plungers 25 and 26.
The seal material in 8, 29 is sent out to the Y-tube 31.

According to the sealing device shown in FIG.
Since the and the electromagnet 60 are integrated, they can be simultaneously arranged on the existing pipe, and workability is improved.
In addition, when the coil 64 is energized, the electromagnet 60 itself is attracted and fixed to the existing pipes 1 and 2, so that the injection device 20 can be attached to the existing pipe without requiring any special fixing member. . That is, the electromagnet 60 can be used as fixing means of the injection device 20. The permanent magnet 40 shown in FIG.
When the injection device 20 is used, the same effect can be obtained by integrating the injection device 20 and the permanent magnet 40.

FIG. 8 shows another embodiment of the sealing equipment.
A control unit 80 for controlling the electromagnet 60 and the motor 70 shown in FIG. 7 is provided. The control unit 80 is attached to a part of the frame 30. Other configurations are the same as those in FIG. The control unit 80 has a function as a control unit that controls the current flowing through the coil 64, and automatically controls the magnitude of the current, the energization time, and the like. On the other hand, the control unit 80 also has a function of controlling the motor 70, and automatically controls the injection amount and the injection speed of the sealing material by the injection device 20.

According to the sealing device shown in FIG. 8, the injection device 20 and the electromagnet 60 can be provided simultaneously as in FIG. 7, so that the workability is improved. Further, since the control unit 80 controls the electromagnet 60 and the motor 70, the operation of injecting the sealing material can be automated.

In the above embodiment, a gas pipe is taken as an example of an existing pipe, but the present invention can be applied to an existing pipe such as a water pipe or a sewer pipe.

[0038]

According to the present invention, the sealing material containing the magnetic material is injected into the joint while the existing pipe is magnetized. Also, a seal layer having a sufficient thickness is formed, and the reliability of the seal can be improved.

[Brief description of the drawings]

FIG. 1 is a view showing a state in which an injection hole for a sealing material is formed in a sealing method according to the present invention.

FIG. 2 is a view showing a state in which a seal facility is provided.

FIG. 3 is an enlarged sectional view near an injection hole.

FIG. 4 is an enlarged sectional view showing a state in which an injection hole is sealed.

FIG. 5 is a sectional view of a joint portion.

FIG. 6 is a view showing another embodiment of the sealing equipment.

FIG. 7 is a view showing another embodiment of the sealing equipment.

FIG. 8 is a view showing another embodiment of the sealing equipment.

FIG. 9 is a sectional view showing a conventional sealing method.

FIG. 10 is a sectional view of a joint part in a conventional sealing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Existing pipe 2 Existing pipe 12 Joint part 13 Drilling device 15 Injection hole 20 Injection device 40 Permanent magnet (magnetization means) 44 Magnetic path 50 Seal material 60 Electromagnet (magnetization means) 63 Iron core 64 Coil 67 Variable resistance (control means) 70 Motor 80 Control unit (control means)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Naoto Hirata 19-18 Sakuradacho, Atsuta-ku, Nagoya City, Aichi Prefecture Inside Higashi Kokugas Co., Ltd. (72) Inventor Takashi Imagawa 19-18, Sakuradacho, Atsuta-ku, Nagoya City, Aichi Prefecture No. Toho Kousama Co., Ltd. No. 18 Inside Toho Gas Co., Ltd. No. 18 Inside Higashi Kunika Chemical Co., Ltd. (72) Inventor Akira Kade 7-6, Bashizashi-cho, Tennoji-ku, Osaka-shi, Osaka In-house Osaka Waterproof Construction Co., Ltd. (72) Inventor Katsuhisa Minami Tennoji, Osaka-shi, Osaka Esashi No. 7 No. 6 Co., Ltd.-cho, Osaka waterproof construction company F-term (reference) 3H025 EA03 EB13 EC01 ED03 EE04 EE05

Claims (8)

[Claims] 1. A method of sealing a joint by injecting a sealing material injection hole into an upper portion of a joint portion of an existing pipe and injecting a seal material from the drilled injection hole, wherein the existing pipe is magnetized. A sealing method for an existing pipe joint, wherein a sealing material mixed with a magnetic material is injected from the injection hole in the state. 2. A method of piercing an injection hole for a seal material above a joint portion of an existing pipe, and sealing the joint portion by injecting a seal material from the pierced injection hole. Means for arranging a magnetic path from one existing pipe across the joint to the other existing pipe, and injecting a sealing material mixed with a magnetic material from the injection hole. Sealing method for pipe joints. 3. The seal for an existing pipe joint according to claim 2, wherein the magnetizing means is a permanent magnet, and is disposed over one existing pipe and the other existing pipe joined thereto. Construction method. 4. The magnetizing means is an electromagnet, comprising an iron core and a coil wound on the iron core, wherein the iron core is disposed over one existing pipe and the other existing pipe joined thereto. The method for sealing an existing pipe joint according to claim 2, which is provided. 5. An apparatus for injecting a sealing material from an injection hole drilled at an upper portion of a joint portion of an existing pipe to seal the joint portion, and an injection device for injecting a sealing material mixed with a magnetic material. A magnetizing means disposed above the existing pipe and forming a magnetic path from one existing pipe across the joint to the other existing pipe; and a seal for the existing pipe joint part. Facility. 6. The sealing equipment for an existing pipe joint according to claim 5, wherein the injection device and the magnetizing means are integrated. 7. An equipment for injecting a sealing material from an injection hole drilled at an upper part of a joint portion of an existing pipe to seal the joint portion, and an injection device for injecting a sealing material mixed with a magnetic material. An iron core and a coil wound around the iron core, wherein the iron core is disposed over one existing pipe and the other existing pipe joined thereto, whereby the joint part is provided from one existing pipe. And a control means for controlling energization of a coil of the electromagnet to the other existing pipe. 8. The control unit, which is a control unit, controls energization of a coil of an electromagnet and controls injection of a sealing material by the injection device.
Sealing equipment for existing pipe joints described in (1).