JPS61271070A - Method for lining inner wall surface of pipe - Google Patents

Abstract

PURPOSE:To line uniformly the inner wall surface of a pipe by inserting an elastic sliding body into the pipe to be treated, injecting a high-viscosity lining material into the rear part of the sliding body, generating a pressure differential between the front and the rear part of the lining material to move the sliding body. CONSTITUTION:In lining the inner wall surface of a pipe, an elastic sliding body 15 is inserted into a pipe 1 to be treated, a lining material 10 having high viscosity and fluidity is injected into the rear part of the sliding body 15 and the inside of the pipe 1 is practically blocked. Then a pressurized fluid is supplied by adjusting an inlet flow regulating valve 5, an outlet flow regulating valve 6 is adjusted and opened and a pressure differential DELTAP is generated between the rear part of the lining material 10 and the front part of the sliding body 15. The lining material 10 and the sliding body 15 are moved by the pressure differential. A comparatively large bore pipe, a pipe including an elbow part, etc., can be lined in uniform thickness.

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 relatively large-diameter buried gas pipes and buried water pipes, and 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.

Therefore, the method of lining the inner wall surface of the pipe with paint etc. is as follows: (1) suspending paint particles in a conveying air flow, passing the mixed fluid into the pipe at high speed, and lining the inner wall surface of the pipe during the flow; A method of forming a coating film on the inner wall surface of a pipe by colliding and adhering paint particles (JP-A-54-156046, JP-A-54-127941, etc.); Supplied into the pipe, paint particles are deposited and laminated on the inner wall surface of the pipe inlet, and the paint layer deposited and laminated on the pipe inner wall surface is sequentially flowed forward by the air flow in the mixed fluid to form a coating film on the pipe inner wall surface. How to
4195 Publication, Special Publication No. 58-13226, etc.),
■ After placing two elastic objects (pigs) at a distance in the pipe and filling the space between the two elastic objects with paint, the two elastic objects are moved forward with the paint sandwiched between them by fluid pressure, etc. A method of forming a coating film on the inner wall surface of a pipe (Japanese Unexamined Patent Publication No. 55-44320, etc.) has been widely used.

Methods (1), (2), and (2) above are all excellent construction methods, and are actually widely used 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,
The loss of paint will be large. Furthermore, since it takes a long time to form a coating on a large-diameter pipe, it is difficult to efficiently form a thick coating, and there is also the problem that the coating on the elbow portion inevitably becomes thin.

Also, in the method (2) above, the coating thickness on the inner wall surface of the pipe is
It is extremely difficult to achieve a R or more, a large-diameter pipe of 4B or more increases the amount of air required, and requires a large-capacity compressor, which is a constraint. Problems remain, such as the coating thickness on the elbow portion being extremely thin compared to the straight pipe portion.

On the other hand, although method (2) is an excellent method when applied to relatively large-diameter pipes, there are still problems to be solved. In other words, (1) a low-viscosity liquid paint is filled between two elastic pigs, and they are moved together in the pipe by fluid pressure, so that the paint that has been attached to the inner wall of the pipe by the rear pig may peel off or It is difficult to form a lining film of 1rIrln or higher even on straight pipe parts because the lining film is scraped off. ◎ At elbow parts, the film is scraped off significantly by the rear pig, so The lining film on the inner wall surface of the curved part is particularly thin, and since two pigs with the O-lining material sandwiched between them slide as a unit, the sliding properties are extremely poor, and there are many small diameter pipes and curved parts. It cannot be used for pipelines, ■ Because the lining material is scraped off by the rear pig, the lining film thickness does not change much even if the moving speed of the pig is changed, and it is difficult to adjust the film thickness. The problem remains.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned problems in the conventional lining of the inner wall of the pipe, namely: It is difficult to increase the thickness of the coating film, and it is difficult to apply it to large-diameter pipes from the viewpoint of work efficiency, paint loss, and securing an air supply source. In the method of moving materials, the lining film is extremely thin, it is almost impossible to control the film thickness, and it is easy to cause clogging accidents during work. can be,
All types of pipelines from small diameter pipes to large diameter pipes can be coated with high efficiency without the need for large capacity fluid supply equipment, and can be coated with a relatively thick coating thickness of 1 to 1.5 degrees or more, even at elbows. It is an object of the present invention to provide a method for lining the inner wall surface of a pipe by which the entire length of the pipe including the pipe can be lined to a uniform thickness.

(Means for Solving the Problems) The present invention involves inserting an elastic sliding body into a pipe to be treated, and injecting a highly viscous fluid lining material behind the sliding body to The inside of the pipe is made into a substantially occluded deaf, and then a pressure difference ΔP is generated between the front and back of the lining material, and the lining material and the sliding body are moved by the pressure difference ΔP, thereby forming a lining film on the wall inside the pipe. This is the basic structure of the invention.

(Function) The sliding body inserted into the pipe and the lining material injected while blocking the pipe are sequentially moved at a constant speed by the pressure difference ΔP between the front and rear of the lining material, and the lining material A lining film is formed on the inner wall surface of the pipe through which the lining material has passed.The thickness of the lining film that is formed is determined by the moving speed and viscosity of the lining material, and by controlling the moving speed, the film thickness can be adjusted. The optimal lining material is a material with relatively high viscosity, little sag, and fluidity.In addition, as a sliding body, it should have elasticity and reduce friction with the inner wall surface of the pipe. The one with the lowest resistance is better.

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 sufficiently polished before lining treatment. The present invention will be specifically described 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 figure, l 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, 14 is a pressure regulator, and 15 is a sliding body made of an elastic material.

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 500 ff1, and the inlet end 1a and outlet end 1b are opened.

Next, as shown in FIG. 1, connect each device, insert the sliding body 15 inward from the open end of the pipe 1, open the valve 11, and inject the lining material 10 to the rear of the sliding body 15. . The lining material 10 has excellent one-layer properties, is in the form of a high viscosity liquid or gel, has good fluidity, has little sagging, and has the characteristics necessary for a lining material (corrosion resistance, safety, etc.). The best option is Specifically, high-viscosity (10,000 to 40,000 cps) epoxy resin paint, high-viscosity cement-based lining material, etc. are optimal.

In this example, the viscosity was approximately 30,000 cp.
The epoxy resin paint of No. s is used as the lining material 10.

The sliding body 15 is made of a flexible and deformable soft elastic material such as rubber or plastic, and its outer diameter is selected to be approximately the same as the inner diameter of the tube 1 to be treated. The sliding body 15 is intended to prevent the highly viscous lining material 10 from sagging forward, and presses it forward along the pipe wall while maintaining a slight frictional resistance between it and the pipe wall. will be moved.

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 1.1 to 1.2 of the required calculation amount. Inject approximately twice as much lining material ■0. A necessary amount of lining material is injected into the pipe so that the lining material 10 is formed in one layer as shown in FIG. 1 and the pipe is closed. At this time, the valve 13 is opened and the lining material tank 9 is opened.
It is convenient to slightly pressurize the inside of the container, as this allows the lining material 10 to be injected more smoothly.

When the injection of the required amount of lining material 10 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 to open.
The lining material 10 injected into the pipe is advanced toward the outlet end 1b at a predetermined speed by the pressure difference ΔP between the rear side of the slider 15 and the front side of the sliding body 15. As the pressurized fluid A to be supplied into the pipe, air, a gas such as 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 stored in a plug shape flows in the direction of the arrow as shown in FIG. 2 while pushing the sliding body 15, and flows inside the pipe. Lining film 10 having a substantially constant thickness t on the wall surface
b is formed. At this time, since the sliding body 15 is present in front of the lining material 10, a large diameter pipe (for example, 5B
-15B), the lining material 10 sag forward and the differential pressure ΔP between the front and rear of the lining material 10 is not lost at all, and the lining material 10 can be moved very smoothly in the state shown in FIG. can be moved.

According to the test results, lining material 10 (viscosity 30ρ0
0 cps, flow velocity of epoxy resin paint) U = 0
．． When the speed is 3 to 3 m/min, a coating thickness of t = 4 to 1 can be obtained in a pipe with a diameter of 50 to 600 mm, and the pressure difference ΔP at the curved part of the lining material 10 is 1~4Kg
/ cI is about 71.

In this embodiment, as shown in FIG.
The movement speed of the lining material 10 is controlled by adjusting the flow rate regulating valves 5 and 6 provided on the inlet side 1a and the outlet side 1b, and adjusting the pressure difference between the upper and downstream sides of the lining material 10 traveling in 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 of adjusting the flow rate of the fluid on the outlet side while keeping the pressure constant may also be used.

Further, a suction device such as a vacuum pump may be provided at the outlet end 1b of the tube to be treated 1, and the lining material 10 and the sliding body 15 may be sucked and moved by the suction device.
Alternatively, supply of the pressurized fluid A and suction by a suction device may be used together.

Furthermore, in the embodiment, the inlet end 1a of the tube to be treated 1
The required amount of lining material 10 is injected at once, but as shown in FIG. , 10a, . . . may proceed simultaneously. In the case where the lining material can be injected into the main pipe and the sliding body can be taken in and out from the middle of the pipe, for example, from a plurality of branch pipes, etc., as shown in Fig. 3 (multiple lining materials 10a).

10a... and the sliding bodies 15a, 15a... can be moved at the same time, so that an extremely long pipe can be processed at one time (effect of the invention).

In the present invention, a sliding body is inserted into a pipe, and a highly viscous lining material is injected behind it, and the lining material that closes the pipe is moved at a predetermined speed by the pressure difference between the front and back. Therefore, even with large diameter pipes, there is no possibility that the lining material will sag forward and the differential pressure ΔP across the lining material will be lost.
, the lining material can be moved extremely smoothly.

In addition, when pressurized fluid A is used, the required flow rate of pressurized fluid A is significantly reduced compared to the conventional lining method, resulting in a significant reduction in energy consumption and a reduction in the size of the fluid pressurizing device. Capacity can be increased and lining of large diameter pipes becomes easier.

Furthermore, since a high viscosity lining material is used and a space is provided behind the lining material, a relatively thick coating film with a thickness of about 1 to 5 mm can be easily formed on the inner wall surface of the pipe. Moreover, the coating thickness does not change at all even at curved portions of the pipe, and a uniform and thick lining film can be formed over the entire length of the pipe.

Moreover, since only one sliding body is used, the lining material and the sliding body can be moved very smoothly, even though the viscosity of the lining material is much higher than in previous pigging methods.

Furthermore, by adjusting the pressure difference between the upper and lower flow rates 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, it is possible to reliably form a lining film of a predetermined thickness, and to improve the mechanical strength of the pipe by utilizing the thickness of the formed coating film.

In addition, even for large-diameter pipes, it is sufficient to inject the amount of lining material necessary to form a film into the pipe inlet end, so there is almost no loss of lining material, making it possible to line the pipe economically. becomes.

[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. FIG. 3 is an explanatory diagram showing an example of injection of another lining material. ■ Pipe to be treated 10 Lining material 10b Lining film 15 Sliding body ΔP pressure difference A Pressurized fluid patent applicant Japan Technology Development Center Co., Ltd. Representative Kiyonori Niino and 1 person Proceedings Amendment (Spontaneous) August 19, 1986 1.Display of the incident Patent application 1986-//3!77 No. 2
, Title of the invention: Method for lining inner pipe walls 3, Relationship with the amended case 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, Subject of amendment: "Detailed Description of the Invention" column 7 of the description, Contents of the amendment

Claims (7)

[Claims] (1) Slide body (15) with elasticity into the tube to be treated (1)
), and at the same time injecting a highly viscous fluid lining material (10) to the rear of the sliding body, the lining material (10) substantially closes the inside of the tube to be treated (1), and then By generating a pressure difference (ΔP) between the front and back of the lining material (10) and causing the lining material (10) and the sliding body (15) to flow, a lining film ( 10b) A method for lining a pipe inner wall surface. (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 of the lining material (10). (5) A method for lining an inner wall surface of a tube according to claim 1, wherein the sliding body (15) is inserted from a plurality of locations in the tube to be treated (1) and the lining material (10) is injected. (6) While keeping the pressure of the pressurized fluid (A) supplied to one side of the lining material (10) constant,
) The lining of the inner wall surface of the pipe according to claim 1, wherein the pressure difference (ΔP) between the front and back of the lining material (10) is adjusted by adjusting the flow rate of the fluid discharged from the other side. Method. (7) 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.