JPS6021789B2 - Leak prevention method for existing buried pipes, etc. - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention prevents leakage accidents in existing buried pipes such as gas pipes, especially in curved pipes such as small pipes and elbows where lining devices cannot be inserted. Regarding how it can be prevented.

[Conventional technology]

If there are cracks in existing underground pipes, such as gas pipes or water supply pipes, or if the joints of the pipes are poorly sealed, the gas or water flowing inside the pipe may leak from the cracks. Conversely, in sewer pipes, groundwater intrudes into the pipes.

Therefore, repair work must be carried out to prevent such leakage. The inventor of the present invention previously developed an apparatus for forming a coating film on the inner surface of a pipe in order to prevent leakage during the above-mentioned repair work, and disclosed the details thereof in Tokugan No. 151727/1983.

This device not only can completely and reliably seal areas where there is a risk of leakage, but it can also form a coating film of uniform thickness on the entire inner surface of the tube, completely preventing leakage and preventing leakage. It is also possible to aim at reinforcement and correction. [Problems to be solved by the invention] However, since the related devices and methods, including this device, perform work while moving the lining device inside the pipe, large diameter pipes and medium diameter pipes are In any case, it could hardly be used for leak prevention work on pipes with curved pipes such as small hollow pipes or elbow pipes.

The present invention is intended to solve the above problems, and its purpose is to provide a uniform coating film on the entire inner surface of not only large diameter pipes but also small diameter pipes or bent pipes in which it is impossible to insert a lining device. The object of the present invention is to provide a method that can completely prevent leakage.

[Structure of the invention]

The present invention forms an air flow that flows at high speed inside the buried pipe, and uses the air flow to transport the adhesive and apply it to the inner surface of the pipe sequentially from the front of the pipe, and then hardens the adhesive. A reinforcing aggregate made of short fibers such as glass fiber is first conveyed by the above-mentioned high air flow, and the reinforcing aggregate is sequentially adhered to the upper surface of the adhesive from the front inside the pipe to form a leak-preventing coating film. This relates to leakage prevention methods for existing buried pipes, etc.

〔Example〕

The present invention will be specifically explained below with reference to an embodiment shown in the attached drawings.

This embodiment shows a case where the construction method according to the present invention is applied to a branch pipe 3 used for supplying gas from a main pipe 1 to each house 2, as shown in FIGS. 1 and 2.

As shown in the figure, the branch pipe 3 has a diameter significantly smaller than that of the main gas pipe 1, and also has a bent pipe portion such as an elbow.

The lining device that enables the construction method of this embodiment essentially separates the house-side end of the branch pipe 3 from the meter 50, and connects the same end to various equipment installed in the lining car 4 through a piping route (described later). A sandblasting tank 5 filled with sand for descaling, a main agent tank 6 and a curing agent tank 7 each filled with a main agent and a curing agent that are mixed to form an adhesive, the main agent tank 6 and the curing agent tank 7.
Discharge pumps 8 and 9 that feed the main agent and curing agent from the pipe to the branch pipes.
, a reinforcing aggregate tank 1 filled with reinforcing aggregate (for example, short fibers such as glass fiber) used to increase the strength of the adhesive.
0, a drain separator 12, and a generator 13.

These various devices are connected to the house-side end of the branch pipe 3 via the required piping route, and at the same end there is a flexible pipe with a first union 18 attached to the tip to facilitate connection with the pipe. A hose 19, a union 20 attached to the other end of the flexible hose, a three-way valve 21 for supplying accelerated air with a built-in ejector, a three-way valve 22 for paint inflow connected to one end of the three-way valve, an on-off valve 23, and piping connections. A joint 25 configured by connecting metal fittings 24 in series is attached.

Next, referring to each piping system, 30 is a first air pressure feeding path that feeds compressed air from the compressor 11 to the sandblasting tank 5 via the drain separator 12, and 31 is a first air pressure path that connects one end to the material discharge port 5 of the sandblasting tank 5.
a and the middle of the first air pressure feeding path 30, and connect the pond end to the joint 2.
5, a sand pressure feeding path removably connected to the piping connection fitting 24; 33 and 34 are the main agent tank 6 and the curing agent tank 7;
The main agent and curing agent are fed to the paint inflow three-way valve 22 of the joint 25 by the discharge pump 8, and from the middle, a main agent pressure feeding path and a hardening agent pressure feeding path are integrated in the mixer 35, and 36 is a compressor 11. A second air pressure passage 37 supplies compressed air from the reinforcing aggregate tank 1 to the reinforcing aggregate tank 1 via the drain separator 12;
a and the second air pressure feeding path 36, and a reinforcing material feeding path whose tip can be detachably connected to the piping connecting fitting 24; This is an accelerated air pressure feeding path that feeds the air through the insparator 12 to the first three-way valve 21 having an internal ejector mechanism.

Regarding other components in the lining device having the above configuration, 40 is a cut-out valve provided at the material outlet 6a of the sandblasting tank 5, and 41 is similarly provided at the material outlet 10a of the reinforcing aggregate tank 10. 42 is a stop valve installed above the three-way valve 22 for inflowing paint; 43 is a three-way valve for inflowing accelerated air; 2
A stop valve 44 installed above the reinforcing aggregate pumping path 37 is installed in the middle of the reinforcing aggregate pumping path 37, and a three-way ejector for pumping compressed air from the second air pumping path 36 via an ejector into the reinforcing aggregate pumping path 37. It is a valve.

Next, a method for preventing leakage of the branch pipe 3 using the lining device having the above configuration will be described.

The timing of lining the branch pipes is before the rust prevention work on the W main pipe, after lining the low main pipe (after the paint film has hardened), and after excavating the N branch pipe extraction part and lining the branch pipe independently of the main pipe. However, in this example, we will explain the case where this is done before the rust prevention work on the main pipe. Furthermore, an adhesive having the following properties was used. Compounding ratio: Main agent: hardening agent = 100 to 100 100〆94 (weight ratio) (capacity ratio) First, as shown in FIG. 1, the house side end 3a of the branch pipe 3 is separated from the meter 50.

After separation, necessary piping is connected to the separation end 3a of the branch pipe 3 using a joint 25 in the form shown in FIG. Next, the compressor 11 is operated to move the compressor as shown by the arrow (Fig. 31).
, the sand is pumped to the sandplast tank 5 and the sand pressure feeding path 31, and the sand is continuously fed to the branch pipe 3 via the joint 25, and the mirror removal work in the branch pipe 3 is performed. Accelerating air can also be sent to the joint 25 and the branch pipe 3 through the pipe 38, thereby increasing efficiency in forming a uniform high-speed flow as described later. After the rust removal is completed, the stop valve 40 stops the supply of sand, and the first air pressure feeding path 5a continues for the required time.
Only compressed air is supplied to the branch pipe 3 through the path of → sand pressure feeding path 3 → joint 25 → branch pipe 3, and residual sand is completely removed.

Furthermore, a uniform pressure-feeding air flow is formed inside the branch pipe by the air pressure-feeding circuit. Next, while holding the air pressure feeding circuit and the acceleration air circuit, the discharge pumps 8 and 9 are driven, the stop valve 42 is opened, and the adhesive is applied to the joint 2.
5 into the branch pipe 3 in a mist or granule form (Fig. 4). As a result, the adhesive is sequentially applied to the inner surface of the branch pipe 3 from the front of the pipe, and the same application is applied over the entire length of the pipe. This is done while forming a constant coating thickness over a period of time, and when the adhesive falls into the main pipe 1, the operation of the discharge pumps 8 and 9 is stopped, and the stop valve 42 is closed.

Note that whether or not the adhesive has reached the tip of the branch pipe 1 is determined by a television camera device 50 used when lining the main pipe 1, as shown in FIG. However, a television camera device exclusively for the branch pipe 3 may be separately provided on the lining car 4. In addition, the same detection is caused by changes in the pressure of the pressure gauge installed in the compressor 11 (the pressure increases as the length of the applied coating film in the branch pipe increases, and the pressure reaches its maximum value when the coating film reaches the final machine). However, the same maximum value becomes a constant value of L, and when this constant value is reached, the discharge pumps 8, 9, etc. can be stopped. This is effective when it is not possible to insert a television camera, etc.

After forming a post-adhesive coating over the entire length of the branch pipe 3 (the adhesive that is the coating has not yet hardened), connect the reinforcing aggregate pumping path to the connecting fitting 24 of the joint 25 as shown in FIG. And the second
Compressed air is supplied to the reinforced bone tank 10 and the reinforced bone village pressure feed path 37 via the air pressure feed path 36, and the three-way valve 44
Using the ejector effect, the reinforcing aggregate is brought into the branch pipe 3 from the reinforcing aggregate 10 through the pressure feed path 37 and the joint 25. Note that even at this point, accelerated air is being fed into the branch pipe 3 from the accelerated air pressure feeding path 38. In this way, the reinforcing aggregate will be bonded to the top of the adhesive from the front of the branch pipe 3 from the inside of the pipe, and a coating film with a sufficient and uniform thickness will be formed over the entire length of the branch pipe 3, and Since the coating film is similarly formed on the curved pipe portion, leakage of gas from the branch pipe 3 can be completely stopped. In addition, the formation state of the said coating film is shown in FIG. 7 to FIG. 10.

Moreover, FIGS. 11 and 12 show the case where adhesive and reinforcing aggregate are further formed in multiple layers as required, while FIG. 13 shows the state of the coating film formed in the case of the police inspector. As shown, the adhesive and reinforcing aggregate can also fill eyelets 60 and threads 61.

〔Effect of the invention〕

5 As described above, the leakage prevention method according to the present invention has the following effects.

A desired lining can be easily formed not only on large diameter pipes but also on pipes with many bends such as small pipes and elbows where it is not possible to insert a lining device.

(b) Since the coating material can be formed in a laminated state, the strength can be extremely increased.

C. Small holes or recesses in threaded portions can also be filled with the adhesive and reinforcing base material, which also has a reinforcing effect.

Ni Compressa's air is heated, so the paint film can be dried with hot air at the same time, significantly shortening the drying time.

This means that gas can be passed through the gas pipe immediately after leakage prevention work is completed. E.5 It can also be effectively used for gas piping and water supply pipes in buildings.

It also has excellent crack resistance due to earthquakes, etc.

G. The degree of lamination can be determined depending on the condition of the pipe (degree of damage). H. Similar effects can be achieved with one-component adhesives.

[Brief explanation of drawings]

Figure 1 is a plan view of the construction state when the leak prevention method according to the present invention is applied to a gas branch pipe, and Figure 2 is a plan view of the construction state when the leak prevention method according to the present invention is applied to a gas branch pipe.
-1 longitudinal cross-sectional view, Figures 3 to 5 are explanatory diagrams of the piping system in each work process of the lining device used in the above construction method, Figure 6 is an enlarged explanatory diagram of the joint, and Figures 7 to 13
The figure is an explanatory diagram of a coating film formed by adhesive and reinforcing aggregate on the inner surface of a branch pipe. In the diagram, 1...main pipe, 3...branch pipe, 6...
...Base agent tank, 7...Curing agent tank, 1
0...Reinforced aggregate tank. Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure Ship chart N Ship Figure 3 Figure 4 Figure 5 Figure 6 Figure 13

Claims (1)

[Scope of Claims] 1. An air flow flowing at high speed is formed inside the buried pipe, and the air flow transports an adhesive to apply it to the inner surface of the pipe sequentially from the front of the pipe, and then the adhesive is applied to the inner surface of the pipe. Before curing, a reinforcing aggregate made of short fibers such as glass fiber is conveyed by the high-speed air flow, and the reinforcing aggregate is sequentially adhered to the top surface of the adhesive from the front inside the pipe to form a leak-preventing coating. A leakage prevention method for existing buried pipes, etc., characterized by forming 2. An air flow is created that flows at high speed inside the buried pipe, and the air flow transports the adhesive and applies it to the inner surface of the pipe sequentially from the front of the pipe.Then, before the adhesive hardens, it is applied to the glass fiber. A reinforcing aggregate made of short fibers such as , etc. is conveyed by the high-speed air flow, and the reinforcing aggregate is bonded to the top surface of the adhesive sequentially from the front inside the pipe, and then the adhesive is conveyed again to bond the reinforcing aggregate to the top surface of the reinforcing aggregate. A leak prevention method for existing buried pipes, etc., characterized in that a leak prevention coating film is formed by applying and sequentially repeating this process.