JPS61268386A - Method for lining linner wall surface of pipe - Google Patents

Abstract

PURPOSE:To make the thickness of a lining film uniform, by injecting a lining material having flowability in a pipe to be treated to bring the interior of the pipe to be treated to a closed state by the lining material and generating pressure difference between both side surfaces of the lining material. CONSTITUTION:A lining material 10 is injected in a pipe 1 to be treated in an amount about 1.1-1.2 times a required calculation amount. After the completion of injection, an inlet flow amount control valve 5 is adjusted not only to supply pressurized fluid A in the pipe but also to adjust and open an outlet flow amount control valve 6. The lining material 10 injected in the pipe is allowed to advance toward the direction of an outlet end 1b at a predetermined speed by the pressure difference DELTAP between both sides of the lining material 10. The lining material 10 injected in the pipe and accumulated in a plug form is formed into a lining film 10b having a constant thickness (t). By this method, the coating thickness of the film can be easily controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a method for lining the inner wall surface of a pipe.
It is used for the rehabilitation of buried gas pipes and water pipes, as well as for the manufacture of lining pipes.

(Conventional technology) To rehabilitate buried gas pipes or water pipes, a sand jet flow (mixed fluid of abrasive material and air flow) is passed through the pipe to polish the inner wall surface of the pipe, and then the inner wall surface of the pipe is coated with epoxy resin paint, etc. The lining method is generally widely used.

As a method for lining the inner wall surface of a pipe with the paint or the like, the following methods (1), (2), and (2) have been widely used. That is, (1) paint particles are suspended in a conveying air flow, the mixed fluid is passed through the pipe at high speed, and the paint particles collide and adhere to the inner wall of the pipe during the flow, thereby forming a coating film on the inner wall of the pipe. Method of forming
No. 046, JP-A-54-127941, etc.),
■Supplying a mixed fluid of paint and air flow into the pipe line, causing paint particles to adhere and stack on the inner wall surface of the pipe inlet, and sequentially move the paint layer adhered and stacked on the inner wall surface of the pipe forward by the air flow in the mixed fluid. (Japanese Patent Publication No. 58-24195, Japanese Patent Publication No. 58-13226, etc.), ■ Two elastic objects (pigs) are placed at a distance in the pipe. After filling the space between both elastic bodies with paint, both elastic bodies are moved forward with the paint sandwiched between them by fluid pressure, etc.
Method of forming a coating film on the inner wall surface of a pipe (Unexamined Japanese Patent Publication No. 55-443
20, etc.).

The above methods (■, ■, and ■) are all dredging methods and have not been put to practical use in the rehabilitation of pipelines in buildings, factories, etc.

However, these methods still have many problems that need to be solved. For example, in method (2) above, since a large amount of paint particles are contained in the mixed fluid discharged from the end of the pipe,
Paint loss will be large. In addition, it is difficult to form a thick coating on large-diameter pipes because it takes a long time to form a coating.Furthermore, it is difficult to form a thick coating on large-diameter pipes. The problem is that it cannot be formed.

In addition, even in the method (2) above, the sliding properties of the elastic object are extremely poor, and as a result, it cannot be applied to pipelines with many curved parts due to the risk of clogging during work, and it is difficult to apply the method over the entire length of the pipeline. There is a problem that a uniform and thick coating film cannot be formed.

On the other hand, method (1) above is a much superior method in practice compared to methods (2) and (2), but (2) it is extremely difficult to reduce the coating thickness to one or more points on the inner wall of the pipe. Koto, 048
Large diameter pipes such as these increase the amount of air required and require a large capacity compressor, so there are restrictions from this point of view, and the thickness of the coating at the zero bend (elbow part) is lower than that of the straight pipe. Problems remain, such as the fact that it is extremely thin compared to the previous version.

The problem with θ is that, as shown in Fig. 7, the dynamic pressure of the air flow H (flow velocity approximately 20 to 80 m/sec) flowing inside the pipe has a component perpendicular to the pipe wall at the elbow. This occurs because the flow of the paint layer S does not flow along the pipe inner wall R at the elbow portion, but flies through the space 0 while being pierced from the pipe inner wall R. As a result, the coating film on the inner wall R of the pipe is only formed by collision and adhesion of paint particles in the air flow, and is extremely thin (approximately 115 mm thick) compared to the straight pipe portion. Incidentally, the flow phenomenon of the paint layer at the elbow portion as shown in FIG. 7 was first confirmed by the inventor of the present invention through a lining test.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned problems in the conventional method of lining the inner wall surface of pipes, namely: , It is difficult to apply to large diameter pipes, ■ It is extremely difficult to increase the thickness of the coating on the inner wall of the pipe (approximately 1.2 mm or more), ■ The thickness of the coating at the elbow part This system aims to solve the problem of extremely thin fluids, etc., and allows all types of pipelines from small diameters to large diameters to be processed with high efficiency without the need for large-capacity fluid supply equipment.
To provide a method for lining the inner wall surface of a pipe by which the entire length of the pipe including the elbow part can be lined to a relatively thick coating thickness of 1 to 1.5 years or more with a uniform thickness. This is the purpose.

(Means for solving the gate opening point) The present invention injects a fluid lining material into a pipe to be treated, substantially closes the inside of the pipe with the lining material, and at the same time, both sides of the lining material are The basic structure of the invention is to form a lining film by generating a pressure difference ΔP between them and causing the lining material to flow due to the pressure difference ΔP.

(Function) Into the pipe 1. The lining material injected into the pipe while blocking it is caused to flow at a constant speed due to the pressure difference ΔP between both sides of the lining material, and a lining film is formed on the inner wall surface of the pipe through which the lining material has passed. Go. The thickness of the lining film formed is determined by the moving speed and viscosity of the lining material, and the film thickness is controlled by controlling the moving speed.

The optimal lining material is a substance that has a relatively high viscosity, has little "sag" and is fluid.

After the lining film is formed, the film is dried by ventilation, etc., and it goes without saying that the inside of the pipe is thoroughly cleaned before lining treatment. The present invention will be specifically explained based on an embodiment of the present invention shown in FIGS.

FIG. 1 is an implementation system diagram of the present invention, and FIG. 2 is an explanatory diagram of coating film formation. In the diagram, 1 is a gas pipe, a water pipe,
2 is a fluid pressurizing device such as a compressor or pump, 3 is a pressure regulator, 4 is a flow meter, 5 is an inlet flow rate adjustment valve, 6 is an outlet flow rate adjustment valve, and 7 is a pipe to be treated such as a fixed length pipe. Lining material discharge valve, 8 lining material in the tank, 9 lining material tank, 10 lining material injected into the pipe,
11, 12, and 13 are valves, and 14 is a pressure regulator.

When lining the inner wall surface of the pipe, if the pipe to be treated 1 is an existing straight pipe, the pipe is first divided into appropriate lengths of about 30 to 30 mm, and the inlet end 1a and the outlet end (b) are opened. .

Further, when the pipe to be treated 1 is a small-diameter branch pipe, one inlet end 1a is opened for every 2 to 10 terminal fittings (valve, etc.) 15 as shown in FIG.

Next, as shown in FIG. 1, each device is connected, the valve 11 is opened, and the lining material IO is injected into the artificial end 1a of the tube to be treated 1. As a lining material IO, it has excellent layer-accumulating properties, is a highly viscous liquid or gel, and has fluidity, and has the characteristics necessary for a lining material (
Corrosion resistance, safety, etc.) are ideal. Specifically, high viscosity (10,000-40,000 cps) epoxy resin paint, high viscosity cement lining material, etc. are most suitable.

In this example, the viscosity was approximately 30,000 c.
ps epoxy resin paint is used as the lining material IO.

The amount of lining material 10 injected into the pipe to be treated 1 is calculated based on the length of the pipe, the thickness of the coating to be formed, the diameter of the pipe, etc., and is usually about 11 to 12 times the required calculated amount. The lining material 10 is injected. In addition, lining material 1 must be inserted into the pipe.
The required amount of lining material is injected so that the lining material is accumulated in the pipe as shown in FIG. 1 and the pipe is closed.

It is convenient to open the valve 13 and slightly pressurize the inside of the lining material tank 9 when injecting the lining material, since the lining material 10 can be injected more smoothly.

When the injection of the required amount of lining material IO is completed, the inlet flow rate adjustment valve 5 is adjusted to supply pressurized fluid A into the pipe, and the outlet flow rate adjustment valve 6 is adjusted and opened to reduce the pressure between both sides of the lining material 10. The lining material 10 injected into the pipe by the difference ΔP is caused to advance toward the outlet end 1b at a predetermined speed. Note that as the pressurized fluid A to be supplied into the pipe, gases such as air and nitrogen, water, etc. can be used, and in this embodiment, compressed air from a compressor is used.

When the pressurized fluid A is supplied into the pipe, the lining material 10 injected into the pipe and accumulated in a plug shape flows in the direction of the arrow in the form shown in FIG. 2, and forms a substantially constant thickness t on the inner wall surface of the pipe.
A lining film 1ob having the following properties is formed.

According to the test results, lining material 10 (viscosity 3 o,
oo.

cps, flow velocity of epoxy resin paint) U = 0.
When the flow rate is 3 to 3 trL/min, a coating film thickness of t = 5 to 1 mm can be obtained in a pipe with a diameter of 25 to 300 pots, and the pressure difference before and after the lining material 10 is △P. 05
~3Kg/crll.

In addition, when the pipe diameter was 25mm, the average coating thickness t of the lining material at this time was about 21rrIn.In this example, as shown in FIG. Tube to be treated 1
The movement speed of the lining material 1O is controlled by adjusting the pressure difference between the upstream and downstream sides of the lining material 1O traveling in the pipe by adjusting the flow rate regulating valves 5.6 provided on the inlet side 1a and the outlet side 1b of the pipe.
This controls the thickness of the coating film formed. However, the moving speed of the lining material 10 can be adjusted by any method, for example, by opening the outlet side and adjusting the flow rate or pressure of the pressurized fluid A applied from the inlet side, or by adjusting the flow rate or pressure of the pressurized fluid A applied from the inlet side. Of course, a method may also be used in which the pressure Pi is kept constant and the flow rate Qo of the outlet side fluid is adjusted.

Further, as shown in FIG. 4, a suction device 16 such as a vacuum pump may be provided at the outlet end 1b of the tube to be treated 1, and the device 16 may suck the lining material IO to make it flow. Supply of pressure fluid A/suction by suction device 16 may be used in combination.

Furthermore, in the embodiment, the inlet end 1a of the tube to be treated l
The required amount of lining material IO is injected at once, but as shown in FIG.
... may proceed at the same time. In addition, if lining materials can be injected into the main pipe from a plurality of branch pipes in the middle of the pipe, for example, a plurality of lining materials 10a, 10a, etc. can be moved at the same time as shown in Fig. 5. This allows extremely long pipelines to be treated at once.

FIG. 6 shows a case where the present invention is applied to a branch pipe. First, a predetermined amount of lining material 10 is applied to the inlet end 1a.
The pressurized fluid A causes the lining material IO to flow at a predetermined speed to the first branch point T1 by opening the valves 15a, 15b, and 15c. Next, when the lining material 10 reaches the first branching point T1 (the arrival time of the lining material IO is calculated from the pressure and flow rate of the fluid A, the pipe diameter, and the pipe length L1), the lining material IO branches into two directions. In order to be
Each end valve 15a.

The opening degrees of 15b and 15c are adjusted to adjust the speed of lining materials 10a and 10a flowing through each branch to a predetermined value, respectively. Note that the amount of lining material lO divided at the first branch point T1 tends to be larger in the straight pipe direction, so it is desirable to adjust the pulp 15a slightly.

Further, in this embodiment, the amount of lining material required for lining the inner wall of the pipe is determined by calculation, and a slightly larger amount of lining material lO than the calculated amount is injected into the inlet end 1a. However, when using a lining material that has a relatively short pipe length and a long curing time for small-diameter pipes, first inject enough lining material to approximately fill the inside of the pipe, and then , an end valve 15 a of each branch pipe,
15b and 1.5c may be sequentially opened to sequentially discharge the lining material injected by the pressurized fluid A. According to this method, if the lining material can be reused or used continuously, thick lining of the inner wall surface of the pipe can be performed extremely easily, highly efficiently, and at low cost.

(Effects of the Invention) In the present invention, a highly viscous lining material is injected into a pipe, and the lining material that has closed the pipe is made to flow at a predetermined speed using pressurized fluid A. As a result, the required flow rate of pressurized fluid A is significantly reduced compared to the conventional lining method, and energy consumption is significantly reduced, as well as the capacity of the fluid pressurizing device can be reduced, making it especially suitable for lining large diameter pipes. becomes easier.

In addition, since a high-viscosity lining material is used, a relatively thick coating film of about 1 to 5 thick coats can be easily formed on the inner wall surface of the pipe, and it can be easily applied even at curved parts of the pipe. The coating thickness does not change at all, and a uniform and thick lining film can be formed over the entire length of the pipe.

Furthermore, by adjusting the pressure difference between the upstream and downstream sides of the lining material flowing in the pipe and changing its movement speed, the coating thickness can be easily controlled, even on large diameter pipes or small diameter pipes. Even for diameter pipes, a lining film of a predetermined thickness can be reliably formed. Moreover, it becomes possible to improve the mechanical strength of the pipe by utilizing the thickness of the formed coating film.

In addition, there is no risk of clogging during operation even with small-diameter pipes, and even with large-diameter pipes, it is sufficient to inject as much lining material into the inlet end of the pipe as necessary to form a film. Therefore, there is almost no loss of lining material, and economical lining is possible.

[Brief explanation of the drawing]

FIG. 1 is an example of an implementation system diagram of the present invention, and FIG. 2 is an explanatory diagram of coating film formation. Figure 3 shows the inlet end 1a when lining a small diameter branch pipe.
This shows the arrangement state of the. FIG. 4 is an implementation system diagram according to another embodiment of the present invention. FIG. 5 is an explanatory diagram showing an example of injection of another lining material. FIG. 6 is an explanatory diagram of lining a small-diameter branch pipe. FIG. 7 is an explanatory diagram of the state of paint flow at the elbow portion of Japanese Patent Publication No. 58-24195. 1 Pipe to be treated 10 Lining material 10 b Lining film △P Pressure difference A Pressurized fluid patent applicant Japan Technology Development Center Co., Ltd. Representative Kiyonori Niino Mail 1z 16RHH81-268386 (Power procedure amendment (self-proposed)) 1986 August 19th, To the Commissioner of the Japan Patent Office, Ci1, Indication of the case, Patent Application No. 1,0-/θ'1100 No. 2, Title of the invention, Method of lining pipe inner wall surface 3, Relationship with the case of the person making the amendment Residence of the patent applicant Address: 3-7-1 Koraibashi, Higashi-ku, Osaka Name:
Japan Technology Development Center Co., Ltd. Representative Nii No
Ken Kiyoshi and 1 other person 4, Agent address: 6, Kitahama Chikaratano Building, 3-39 Kitahama, Higashi-ku, Osaka City, Subject of amendment: "Detailed description of the invention" column 7 of the description, Contents of the amendment (1) Description/ /page 4~. rth row r O, 3~3 r
Correct nAin J to "3-30tn/+ko". (2) Description//page 10th r) m/ux
Correct J by r10m/+in Jt.

Claims (8)

[Claims] (1) A fluid lining material (10) is injected into the pipe to be treated (1), the inside of the pipe to be treated (1) is substantially closed off by the lining material (10), and the lining material (10) A pressure difference (△P) is generated between both sides of the pipe, and the lining material (10) is caused to flow by the pressure difference (△P), thereby forming a lining film (10b). How to line the wall. (2) A method for lining an inner wall surface of a pipe according to claim 1, wherein a pressure difference (ΔP) is generated by the pressurized fluid (A) supplied from one side of the lining material (10). (3) A method for lining an inner wall surface of a pipe according to claim 1, wherein a pressure difference (ΔP) is generated by reducing the pressure in the inner space of the pipe on one side of the lining material (10). (4) Pressurized fluid (A) from one side of the lining material (10)
A method for lining an inner wall surface of a pipe according to claim 1, wherein a pressure difference (ΔP) is generated by supplying the lining material and reducing the pressure in the space on the other side between the lining materials. (5) A method for lining an inner wall surface of a pipe according to claim 1, wherein the lining material is injected between the inlet end of the pipe to be treated (1). (6) Lining material (1
0) is injected into the pipe inner wall surface according to claim 1. (7) Keep the pressure (Pi) of the pressurized fluid (A) supplied to one side of the lining material (10) constant, and adjust the flow rate (Qo) of the fluid discharged from the other side between the lining materials. Due to this, the pressure difference between both sides of the lining material (10) (
A method for lining a pipe inner wall surface according to claim 2, wherein ΔP) is adjusted. (8) The method for lining an inner wall surface of a pipe according to claim 1, wherein the lining material (10) is a high-viscosity epoxy resin lining material.