JPS5851961A - Finishing of paint film on inside wall of pipe and container - Google Patents

Abstract

PURPOSE:To prevent the formation of pinholes and to make it possible to simply remove a clogging substance coming into a branch pipe part, by generating negative pressure in a pipe to be lined or a container to be painted to simply remove air bubbles present in the coating applied to the inside wall surface thereof. CONSTITUTION:Joints at both ends of a pipe 1 to be lined is detached and a blind joint 2 is attached to the opening part 3 at one end thereof and a suction apparatus 6 is attached to the opening part 4 at the other end thereof through a connecting metal fitting 5. This apparatus 6 is operated to generate negative pressure in the pipe 1 to be lined to suck air bubbles generated to the surface of a coating A to defoam said coating. In addition, a lining material B which enters a branch pipe 1' and clogs the same is also drawn out to the direction of the apparatus by pressure difference. When the blind joint 2 is opened at this time, the lining material B as the clogging substance can be taken out rapidly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for removing coating properties on the inner wall surfaces of pipes such as water pipes and gas pipes, and on the inner wall surfaces of containers such as pressure tanks.
It is particularly effective in coating the inner walls of existing pipes such as buried pipes and pipes inside buildings. Steel pipes are often used for water and gas pipes.

However, after many years of use, water pipes have developed rust, causing red water to flow out and a decrease in the amount of water flowing through the pipes. In recent years, as a countermeasure against this problem, rust prevention work has been taken to remove scale such as rust inside these pipes and then line the inside with epoxy resin or paint to suppress the formation of rust and extend the life of the pipe. . Its workability is as follows:
- The method described in 147042, etc. In other words, attach a high-speed rotating spray nozzle to the tip of the hose, insert it into the pipe to be lined, and while spraying the lining material, gradually pull the pipe back toward the front from the end of the tube. Limb lining can be done by lining the inner surface, or by applying lining material in a mist or bubbles to high-speed airflow as described in Japanese Patent Applications 53-65501, 1987-756, and 1987-115329. Many methods are used, such as passing it through a pipe to form a coating film.

However, when lining or painting with these methods, air is drawn into the paint film, which causes air bubbles to form and pinholes to form when the paint film dries and hardens and the temperature rises.

Because these pinholes lead to the so-called early reoccurrence of the problem, the industry spent a huge amount of research and testing money trying to remove the air that causes these pinholes, but no solution was found.

On the other hand, if the pipe to be lined has branches or branch pipes, accidents often occur in which the lining material gets into the pipes and causes blockages, resulting in huge costs for rework. The present invention is a method invented to meet the strong demands of the industry and solve these problems quickly and inexpensively.

The details of the present invention will be explained below with reference to the drawings.

In FIG. 1, (1) is a pipe to be lined. This is, for example, a water pipe or waste pipe that is laid underground or inside a building, and has branches or bends in the middle, and the inner surface is coated with a lining coating using the well-known method mentioned above. ing. A blind (2) is attached to the opening (3) created by removing the joints at both ends of the pipe to be lined (1), and a vacuum is connected to the opening (4) at the other end through the connecting fitting (5). Suction devices such as pumps and suction blowers (6
) is the installation.

Now, when this suction device (6) is operated to suck, a negative pressure is generated inside the pipe to be lined, and air bubbles generated on the coating surface are drawn out and foamed.

Also, the lining material gets into the branch pipe (1) and the branch pipe (1)
The lining material (b) blocking the is also pulled out in the direction of the suction device (6) due to the pressure difference. At this time, Mekura (2
), the lining material that is the blockage can be removed quickly.

As described above, according to the method of the present invention, it is possible to degas the coating surface easily and inexpensively, and also to remove blockages that have entered branch pipes and the like.

A similar effect can also be achieved by coating the inner wall surface of the tank.

[Brief explanation of drawings]

FIG. 1 is a flowchart illustrating an embodiment of the method according to the present invention. FIG. 2 is a partially enlarged view of the lining coating surface. FIG. 3 is a high-pressure fluid as described in claim (6) as a power source. This is an example of a device. Blank (3) (4) is the opening (5) is the connection fitting
(6) is a suction device (7) is a ring-shaped nozzle chamber (8)
(c) The main body of the suction device powered by high-pressure fluid (3) is the lining coating (c) is the blockage such as lining material (a) is the high-pressure fluid (Ol is the suction air patent applicant Kane Kura Fujii C\α) t-Suction Proceedings Amendment Letter dated October 12, 1980 To the Commissioner of the Patent Office (To the Patent Office Examiner) 3. Person making the amendment

Claims (7)

[Claims] (1) A method of coating the inner wall surfaces of pipes and containers, which is characterized by creating a negative pressure inside the pipe to be lined and the container to be coated, thereby removing air bubbles in the coating film applied to the inner wall surfaces and sealing pinholes. Membrane finishing method. (2) A pipe inner wall surface that is characterized by creating a negative pressure inside the pipe to be lined, thereby sucking out the paint that has entered the inside of the pipe branching from the pipe to be lined, thereby eliminating blockages in the branch pipes, etc. Paint film finishing method. (3) A method for finishing a coating film on an inner wall surface of a pipe or an inner wall surface of a container, characterized in that a vacuum pump is used as the negative pressure suction device used in claim (1) or (2). (4) Coating the inner wall surface of a pipe or the inner wall surface of a container characterized in that a blower is used as the negative pressure suction device used in claim (1) or (2)! Finishing method. (5) A method for finishing a coating film on an inner wall surface of a pipe or an inner wall surface of a container, characterized in that a nutsch pump is used as the negative pressure suction device used in claim (1) or (2). (6) Coating on the inner wall surface of a pipe or inner wall surface of a container, characterized in that a device powered by high-pressure fluid is used as the negative pressure suction device used in claim (1) or (2).” Second method. (7) A method for forming a coating film on an inner wall surface of a pipe and an inner wall surface of a container, characterized in that the coating material according to claim (1) or (2) is an epoxy resin.