JPS60206623A - Method of repairing existing pipe and sealing tube used therefor - Google Patents

Abstract

PURPOSE:To line easily the inner surface of an existing pipe, by covering a lining tube, to which an adhesive has been applied, with a protective film, and spreading the lining tube in the existing pipe by pressing rollers while releasing the protective film. CONSTITUTION:An adhesive 3 is applied onto a lining tube 2, and a protective film 4 is placed thereon to produce a sealing tube 1. The tube 1 is inserted into an existing pipe, and while the protective film is being released, the lining tube 2 is forcibly joined onto the existing pipe inner surface by pressing rollers. The method can be applied to a newly laied pipe or a pipe arranged on the ground. Since the joining is carried out mechanically using pressing rollers in conformity with the inner diameter of the pipe, the joining reliability is high.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for repairing existing pipes and a seal tube used in the method. More specifically, it relates to a method of repairing an existing pipe by cutting a part of the pipe as it is laid and lining the inner surface of the pipe with a tube made of synthetic resin, and a seal tube suitable for the method. It is.

Pipes such as water pipes and gas pipes deteriorate over time after they have been installed, causing rust and scale to form on their inner surfaces, as well as limescale and dust adhering to these pipes, creating a complex structure that causes friction against the fluid flowing inside the pipes. An increase in the coefficient and a decrease in the cross-sectional area of the piping cause pressure loss, a drop in flow rate, and the generation of red water, completely impairing the functionality of the piping.

Moreover, underground pipes require a great deal of labor and expense, such as finding open holes, repairing pipes by excavating, replacing new pipes, and backfilling excavated parts. In such areas, problems such as long-term traffic obstruction and construction noise are occurring, making it increasingly difficult to replace new pipes.

To this end, in order to make effective use of the aging existing pipes and to reduce construction period, economy, and resource saving, we inserted polyethylene pipes with a slightly smaller diameter into the existing pipes, and created gaps between the existing pipes and the polyethylene pipes. There is a method of repairing a pipe by injecting cement milk into the pipe, and a method of cleaning the inside of an existing pipe, applying an adhesive to the inner surface of the tube, and then using air pressure to turn the tube upside down, so that the adhesive surface is continuous with the inner surface of the existing pipe. A method of repairing existing pipes by lining them with adhesive has been proposed.

However, the above-mentioned repair method of inserting a polyethylene pipe is
After repair, the pipe diameter becomes extremely small and sufficient flow cannot be obtained. Additionally, one construction area is limited due to expansion and contraction due to temperature changes. On the other hand, the tube inversion repair method uses only air pressure to invert the tube, so if the tube diameter is small, the wall thickness is large, or the tube is long, high air pressure is required to invert the tube. In some cases, it may not be possible to insert the In addition, this method requires turning the tube inside out, which limits the types of tubes that can be used.
It is not possible to select the optimal tube material for the fluid used. Therefore, there are problems with the material, wall thickness, flexibility, etc. of the tube, and unless the tube has rubber elasticity, it will buckle when inverted, making it impossible to provide a good lining.

The present invention has focused on such circumstances, and aims to solve the above-mentioned drawbacks of the conventional technology.It is an object of the present invention to solve the above-mentioned drawbacks of the conventional technology. It is characterized by not causing the occurrence of
The object of the present invention is to provide a method for repairing an existing pipe and a seal tube used in the method.

In other words, the present invention includes (a) a step of cutting an existing pipe at predetermined distances, removing and cleaning internal clutter and scale to prepare a base for adhesive, and (b) a lining made of synthetic resin or the like. A step of applying an adhesive to the outer surface of the tube, further covering the protective film, and inserting the integrated seal tube into the existing pipe, and (c) inverting the protective film of the seal tube and pulling it backward. The present invention relates to a method for repairing an existing pipe, which comprises a step of peeling off the lining tube and simultaneously compressing the inner wall of the lining tube to the inner wall of the existing pipe, and a seal tube used in the method.

With the above method, it is possible to repair old existing pipes by lining them with tubes. After lining, the inner surface of the repaired pipe becomes a smooth wall with less resistance, increasing flow rate and preventing internal corrosion and electrolytic corrosion.Furthermore, repair work is easy, reducing construction time and costs. It is possible to achieve this goal.

Examples Hereinafter, the configuration and effects of the present invention will be specifically explained based on the illustrated examples. However, the illustrated examples are merely representative examples, and various modifications may be made within the technical scope of the present invention. It is also possible to implement it with some changes. In the example,
Although the present invention is directed to underground existing pipes, it goes without saying that the present invention can be applied to above-ground pipes as well as newly installed pipes.

FIG. 1 is a perspective view of an embodiment of a seal chew used in the method of repairing an existing pipe according to the present invention.

The seal tube 1 is composed of a lining tube 2 having a tubular shape or a crushed shape, an adhesive layer 3 applied around the lining tube 2, and a protective film 4 covering the outside of the lining tube 2.

The lining tube 2 and the protective film 4 can be made of the same or different materials, but since the lining tube 2 comes into direct contact with the fluid, the material most suitable for the fluid used is selected and used. If the piping to be repaired is short or if there is no obstacle for inserting the seal tube l in above-ground piping, it may be a rigid body than the lining tube 2j, but usually it is It is preferably made of a flexible material because it is pushed out and crimped onto the inner wall of the tube, and then rolled up for storage and transportation. Furthermore, as will be described later, the protective film 4 applied to the outer periphery of the adhesive layer 3 is peeled off by being reversed or folded back, so it must be formed of a soft material. In addition, the protective film 4 has good releasability from the adhesive layer 3,
If necessary, it is coated with a type III agent, and it is preferable that the protective film 4 not crack in the longitudinal direction during construction.

Examples of materials for the lying tube 2 and the protective film 4 include polyolefin resins such as homopolymers such as polyethylene, polypropylene, polybutene-1, and poly-4-methylpentene-1, or copolymers thereof, and nylon. -6, polyamide resins such as nylon-66, nylon-11, and nylon-12, polyester resins such as polyethylene terephthalate, thermoplastic resins such as polyvinyl alcohol resins and polyvinyl chloride resins, elastic bodies such as natural rubber and synthetic rubber, Examples include stretchable woven or nonwoven fabrics coated with the thermoplastic resin or elastic material. Among these, polyethylene, nylon, polyvinyl chloride, etc.

Preferable in terms of corrosion resistance, price, and workability.

The adhesive used for the adhesive layer 3 is not particularly limited, but it needs to exhibit good adhesion to the pipe to be repaired and the selected material of the lining tube 2. There are various adhesives such as evaporation curing type, heat curing type, hot melt type, pressure sensitive type, water curing type, and two-component curing type.In the present invention, we use heat curing type, hot melt type, Water-curing adhesives, two-component curing adhesives, and the like are suitable, and the type thereof is appropriately selected depending on the material of the pipe to be repaired and the lining tube 2.

The method for repairing existing pipes according to the present invention will be described below with reference to the drawings.

a. Cutting process The method for repairing existing pipes of the present invention can be applied to both above-ground pipes and underground pipes.

The piping shown in Figure 2 is an example of an underground pipe. After cleaning the inner surface of the existing pipe ii and applying an adhesive base treatment, the lining is repaired by inserting a seal tube and press-fitting the lining tube to the inner wall of the pipe.

First, a shaft 12 is excavated at an appropriate distance from the existing pipework 1 to be repaired. Next, both ends of the existing pipe 11 exposed in the vertical shape 12 are cut by a certain dimension to remove the existing pipe 11.
Openings 13a and 13b are provided in the openings 13a and 13b. It is necessary to select locations for excavation and cutting of existing pipes where it is easy to insert the seal tube and clean the inside of the pipe.If there is an L-shaped pipe or T-shaped pipe, it is desirable to excavate and cut that part. .

b. Cleaning process After the openings 13a and 13b are provided, an auger 14 or the like is inserted into the repair section from the opening 13a on one side to the opening 13b on the other side depending on the state of the scale or confusion in the existing pipe 11. Perform preliminary cleaning. If the repair section is long,
Preliminary cleaning by pig washing is economical and preferred.

Next, depending on the state of the rust, the anchors and scale stuck inside the pipe are scraped off using a scraper, wire brush, etc., and the pipe is cleaned by washing with water. After this cleaning, sandblasting cleaning is performed by spraying high-pressure water and sand to complete the surface treatment. When using a water-soluble adhesive, a small amount of water may remain, but when using other adhesives, it is necessary to dry the inside of the existing pipe with a dryer.

Also, depending on the strength required for the repair work after repair, the material of the pipe to be repaired, the material of the lining tube and adhesive used, and other conditions, one of the above cleaning tasks may be omitted or added. It is possible.

C. Inserting the seal tube After cleaning the inside of the existing pipe, insert the wire rope 16 wound around the winch 15 from the opening 13b at the other end to the opening 13a.
Insert it toward. Next, the tip of the seal tube 1 let out from the reel 18 is attached to the chunk 17 at the tip of the wire rope 16 coming out of the opening 13a. This chunk 17 may have an appropriate structure. At this time, after fixing the rope 20 wound around another winch 19 to the chuck F, the winch 15 is hoisted to move the seal tube l and the rope 20 onto the existing pipe 11.
is inserted from the opening 13a to the opening 13b. Note that the rope 20 is used to pull out the protective film 4 from the opening 13a while peeling it off in the subsequent process. Preferably multiple copies.

l The seal tube l inserted into the existing pipe 11 is inserted into the opening 13 with both ends left slightly longer for terminal treatment.
Cut at a.

In this way, the tip of the seal tube l is connected to the opening 13. at the other end. Pull it out to b and slightly peel off the protective film 4 at the tip of the seal tube l. In this case, as shown in FIG. 1, the protective film 4 is torn into two pieces (or a plurality of pieces) in the longitudinal direction, and each piece is fixed to the rope 20. On the other hand, the end of the lining tube 2 is connected to the opening 13 of the existing pipe 11.
Fix it to b.

d. Lining process Next, in order to press and expand the inner surface of the lining tube 2 fixed to the opening 13b of the existing pipe 11, a pressure roller 21, which is given elastic force by a spring corresponding to the inner diameter of the existing pipe 11, is used. Using pneumatic pressure or the flexible shaft 22, the inside of the lining tube 2 is rotated by the rotation 1123, expelling air to avoid air pockets, and making the insertion speed of the pressure roller 21 and the peeling speed of the protective film 4 the same. The protective film 4 is pressed onto the inner wall of the existing pipe 11 through the opening 1 using the rope 20.
Pull it towards 3a. The adhesive layer 3 applied to the outer surface of the lining tube 2 in this manner is pressed against the inner wall of the existing pipe 11, and lining progresses one after another. It is desirable that the pressure roller 21 be rotated in the opposite direction and reciprocated two or three times to ensure complete adhesion.

e. Post-processing process After the lining is completed, connect the connecting pipe at the opening,
There is no problem in immediately applying fluid and further crimping using fluid pressure, but if there is sufficient curing time, attach flanges and pressure gauges to the openings at both ends of the lining section to apply internal pressure and maintain it for a long period of time. It is desirable to allow the adhesive to completely cure.

Further, if the material of the lining tube is made of polyolefin such as polyethylene, a hot melt type adhesive is used as the adhesive. In that case, it is necessary to use a heated pressure roller or to use a heat source necessary for bonding, such as steam heat or hot air, in combination.

After curing, connect the pipes at the cut openings 13a and 13b, and if it is a buried pipe, apply anti-corrosion treatment (wrapping with jute or anti-corrosion tape) to the outer surface of the connecting pipe through which fluid passes, backfill the excavated part, and as needed. The construction work will be completed by restoring the pavement surface.

Other Embodiments 1 A variation of the method described above is the use of a two-part reactive adhesive. In that case, after cleaning the inside of the existing pipe, a curing agent or main agent of a two-component reactive adhesive such as an epoxy resin is sprayed onto the inner wall of the existing pipe 11 using a spray nozzle or the like. On the other hand, on the outer surface of the lining tube 2,
The adhesive M3 is formed by applying the main agent or hardening agent of the adhesive (that is, the one that is the opposite of the one applied to the existing pipe 11), and the protective film 4 is placed on top of the adhesive M3 to form an integrated seal tube l. is manufactured and inserted into the existing pipe 11. The lining tube 2 is crimped onto the inner wall of the existing pipe 1, and the base material and the curing agent are reacted to form a strong bond, using the same method as described above.

Other Embodiment 2 In addition, in another modified method, when removing rust and scale inside the existing pipe 11, the rust is not completely removed and the remaining rust and scale are left as they are, and then polyurethane It is also possible to spray resin, resin mortar, or the like onto the inner wall of the existing pipe 11 to fix rust and foreign matter and create a base condition for easy adhesion, and then perform the same repair work as described above.

In each of the above repair methods, tubes made of synthetic resin or the like may be coated with adhesive at the construction site, covered with a protective film to create an integrated seal tube, and inserted into the existing pipe one after another. It is preferable to manufacture the integrated seal tube elsewhere, fold it, and wind it around a reel or the like for use because it is advantageous in terms of construction time, construction time, and cost.

In the method of repairing an existing pipe using tube lining of the present invention, the material of the seal tube to be used can be arbitrarily selected according to the type of fluid in the pipe, and
Alternatively, hoses can be used, so unlike traditional lining work, only a thin coating can be formed, or peeling due to pinholes, swelling of the coating, etc.
No damage to the lining occurs, and if the repair method according to the present invention is carried out, the pipe can be used permanently.

In addition, in the method for repairing existing pipes of the present invention, since adhesive can be applied to the outer surface of the tube in the foreground, it is possible to select and control the adhesive, and when gluing, the adhesive is mechanically applied using a pressure roller. Since it is crimped, the adhesion is highly reliable. In addition, since a tube with almost the same diameter as the existing pipe is inserted, the flow rate of the repaired pipe increases by the difference between the rough surface of the steel pipe before repair and the frictional resistance (flow velocity coefficient) of the used tube after repair. Problems such as easy generation do not occur, a desired flow rate can be secured semi-permanently, and corrosion and generation of red water can be effectively prevented.

Furthermore, the method of repairing existing pipes of the present invention is effective not only for buried pipes but also for newly installed pipes and above-ground pipes, and there is no inconvenience such as reinforcing the pipe rank due to increased weight of the pipe, and it is practical. It is a useful repair or lining method.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a seal tube used in the method of the present invention, FIGS. 2 to 4 are schematic longitudinal sectional views of steps showing an embodiment of the method of the present invention, and FIG. FIG. 3 shows the seal tube insertion step, and FIG. 4 shows the lining step. DESCRIPTION OF SYMBOLS 1... Seal tube, 2... Lining tube 3... Adhesive layer, 4... Protective film 11...
Existing pipe 12... Vertical, 13&, 13b, -, opening, 14-... Auger 15
．． 19... winch, 16... wire rope 17.
...Chuck, 18...Reel 20...Rope,
21... Pressure roller 22... Flexible shaft, 23... Rotating machine Patent applicant Japan Petrochemical Co., Ltd. Same as above Agent of Pond Engineering Co., Ltd.
Attorney Mae Hajime Shima Procedural Amendment May 4, 1980 Commissioner of the Patent Office Kazuo Wakasugi 2. Name of Invention Method for repairing existing pipes and seal tubes used in the method 3. Case of the person making the amendment. Relationship Patent applicant name: Japan Petrochemical Co., Ltd. (1 idiot) 4, agent address: Kawamura Building 6, 7-11-7 Ueno, Taito-ku, Tokyo
, Number of inventions increased by amendment None 7, Subject of amendment

Claims (7)

[Claims] (1) A method for repairing wide pipes consisting of the following steps (a) to (c): (b) cutting the existing pipes at predetermined distances, removing and cleaning internal clutter and scale; (b) A step of applying an adhesive to the outer surface of a lining tube made of synthetic resin, etc., and inserting an integrated seal tube covered with a protective film into the existing pipe. and (c) a step of crimping the lining tube onto the inner wall of the existing pipe by inverting and peeling off the protective film of the seal tube while pulling it backward, and simultaneously pushing and expanding the inner wall surface of the lining tube. (2) In step (a) above, after applying a base treatment for adhesive, apply a curing agent or main agent of a two-component reactive adhesive such as epoxy resin to the inner wall of the existing pipe, and in step (b) above.
Claim 1, wherein a seal tube is used in which a main ingredient or a curing agent of a two-component reactive adhesive is applied to the outer surface of the lining tube as an adhesive, and a protective film is provided and integrated. Method of repairing existing pipes as described in . (3) In the above step (a), after removing the clutter and scale inside the existing pipe, polyurethane resin or resin mortar is sprayed onto the inner wall of the existing pipe to fix the remaining rust and scale. A method for repairing an existing pipe according to claim 1, which comprises performing a surface treatment. (4) Existing pipe made of a flexible material and consisting of a lining tube in the shape of a tubular or crushed tubular material, an adhesive layer formed on the outer periphery of the lining tube, and a protective film applied to the outside of the adhesive layer. Repair seal tube 6 (5) The seal tube according to claim 4, wherein the flexible material is a thermoplastic resin. (6) The seal tube according to claim 5, wherein the thermoplastic resin is made of any one of polyolefin resin, polyamide resin, and polyvinyl chloride resin. (7) The seal tube according to claim 4, wherein the protective film is made of a material that is easily torn in the longitudinal direction of the lining tube.