JPH0521736B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is used for lining pipes mainly buried underground, such as gas pipes, water pipes, sewer pipes, power lines, communication lines, etc. It concerns a method for doing so.

When lining this type of pipe, a flexible cylindrical lining material whose inner surface is coated with adhesive is inserted into the pipe while being turned over using fluid pressure, and the inside-out lining material is applied to the inner surface of the pipe using the fluid pressure. This is done by pressing and bonding.

In this method, both the pipe line and the lining material have airtightness, and the adhesive area is large, so a reaction-curing adhesive that does not contain volatile components is used as the adhesive. Since the reaction rate of the reaction-curing adhesive increases with heat, it is preferable to heat the interior of the lining material to accelerate curing and complete adhesion at an early stage.

Prior Art Conventionally, in this type of pipe lining method, the method of heating and accelerating the curing of the adhesive is to send a heat medium such as hot air, pressurized steam, or hot water into the lining material inserted into the pipe. There is a known method of heating it by heating it. However, with these methods, it is difficult to uniformly heat the entire length of a long pipe, and curing tends to be uneven.

Therefore, as a method of uniformly heating the entire length of the pipe and curing the adhesive evenly over the entire length,
A method described in Japanese Patent Publication No. 60-21529 is known. This method involves forming a coating layer on the inner surface of a cylindrical fabric at the free end of a flexible lining material whose inner surface is coated with a thermosetting adhesive, and forming a large number of fine leakage holes along its entire length. The lining material is inserted into the pipeline while being reversed so that the inside becomes the outside by fluid pressure, and the hose is inserted into the lining material, and the reversed lining material is applied to the fluid pressure. The lining material is crimped onto the inner surface of the pipe via the adhesive, and then pressurized steam is fed into the hose while maintaining the lining material crimped onto the pipe, and the pressurized water vapor is transferred from the leak hole to the hose. The adhesive is allowed to leak between the adhesive and the lining material, and the adhesive is heated and cured through the lining material.

Problems to be Solved by the Invention However, in this method, since the surface of the hose is made of cylindrical fabric, when the hose is inserted into the lining material that is pressed against the inner surface of the pipe, the inner surface of the lining material and the hose may come into contact with each other. The frictional resistance is large, and a large amount of force is required to insert the hose, and
A large tension is applied to the inserted hose. Therefore, especially at the bend in the pipe, the hose is strongly pressed inward by the bend, flattening the hose, and preventing the passage of heat medium.

FIG. 2 shows this state, where the pipe line 1
A lining material 2 is pressure-welded to the inner surface of the pipe line 1 through a reaction-curing adhesive such as an epoxy resin.
Two continuous bent portions 3a and 3b are formed in the. Note that this condition is not a particularly special condition in various underground pipeline systems, but is a condition that frequently occurs when pipelines are laid around underground obstacles.

When the hose 4 is inserted into such a conduit, the hose 4 extends along the inside of the bent portions 3a, 3b as shown in the drawing, and the tension of the hose 4 causes the portion along the inside of the bent portions 3a, 3b to is lining material 2
It is pressed so hard that it becomes flat and flat, making it impossible for the heating medium to pass through it. Therefore, even if the heat medium is sent from the left side in the drawing, the heat medium is blocked at the bent portions 3a and 3b, and a sufficient amount of heat medium is not sent into the hose 4 on the right side. Therefore, a sufficient amount of heat medium leaks into the lining material on the left side of the bent portions 3a and 3b of the conduit, and the adhesive is sufficiently heated, and the adhesive can be cured quickly.
Little or no heat medium is supplied into the lining material to the right of a and 3b, making it impossible to promote curing of the adhesive.

In particular, since the hose 4 has a cylindrical fabric 5 made of fibers on its outer surface and a synthetic resin coating layer 6 formed on its inner surface, when the hose 4 is flattened at the bent portions 3a and 3b, On the inner surface of the hose 4, the coating layers 6 are pressed against each other, and it is almost impossible for the heat medium to pass therethrough.

The present invention has been made in view of the above circumstances, and provides a method for lining a pipe by promoting the curing of an adhesive by the method described above, in which the hose is not blocked at the bent portion of the pipe. It is an object of the present invention to provide a method in which a heat medium is spread over the entire length of the lining material, and the adhesive can be uniformly cured by uniformly heating the lining material over its entire length.

Means for Solving the Problems According to the present invention, a lining material is brought into pressure contact with the inner surface of a pipe via a reaction-curing adhesive, and a synthetic resin coating layer is provided on the outer surface of a cylindrical fabric within the lining material. A flexible air leak pipe formed by forming a large number of fine leak holes in the coating layer is inserted, and fluid pressure is applied within the lining material to bring the lining material into pressure contact with the inner surface of the pipe. While maintaining the temperature, a gaseous heating medium is pressurized into the leakage pipe to cause the heating medium to leak from the leakage hole, and the heat of the heating medium accelerates the curing of the adhesive, thereby attaching the lining material to the pipe. It is characterized by being adhesive.

In the present invention, an air leak pipe is used in which the inside and outside surfaces of the hose are reversed in the conventional method described above, and a coating layer is formed on the outer surface of the cylindrical fabric. The injected heating medium is spread over the entire length of the leakage pipe, making it possible to heat the entire pipe evenly.

Effect In the present invention, since the air leak pipe 7 has the coating layer 5 on its outer surface, the air leak pipe 7
When inserted into the lining material 2 that is pressed against the inner surface of the pipe, the frictional resistance between the leakage pipe 7 and the lining material 2 becomes small, allowing the pipe to slide smoothly and be inserted with a small force.

Therefore, the force required to insert the air leak pipe 7 is small, and the tension applied to the air leak pipe 7 in the inserted state is small.

Therefore, at the bent portions 3a and 3b of the conduit 1, the leakage pipe 7
a, 3b, but its bent portion 3
A and 3b are not strongly pressed as in the prior art example.

Further, since the cylindrical fabric 5 is provided inside the air leak pipe 7, the air leak pipe 7 is connected to the bent portion 3 of the pipe line 1.
Even in the flattened state at a and 3b, the heat medium can pass through between the fibers of the cylindrical fabric 5.

Therefore, in the present invention, when the air leak pipe 7 is inserted into the lining material 2 in the pipe line 1, the air leak pipe 7
Since no internal pressure is built up in the bending portions 3a and 3b, the leakage pipe 7 is flattened. Here, when a heat medium is sent from the left side of the air leak pipe 7 in the figure, the air leak pipe 7 on the left side of the bent portion 3a expands due to the pressure of the heat medium, and the heat medium is transferred to the fibers of the cylindrical fabric 5 at the bent portion 3a. Proceed through the space.

The heat medium passing through the bent part 3a causes the air leak pipe 7 between the bent part 3a and the bent part 3b to swell, and the internal pressure of the air leak pipe 7 before and after the bent part 3a causes the air leak pipe 7 of the bent part 3a to expand. is expanded, and the heating medium can freely flow through the swollen portion of the leakage pipe 7.

Then, when the heat medium can freely flow between the bends 3a and 3b, the air leak pipe 7 along the bends 3b is also expanded in the same way, and the heat medium flows through this part. be able to pass through.

Finally, the heat medium passes through the bent portions 3a and 3b, can flow to the right in the figure, spreads over the entire length of the air leak pipe 7, and passes through the leak hole of the air leak pipe 7 to the air leak pipe 7 and the lining material. 2 and heats the lining material 2 to harden the adhesive.

Hardening of the Invention According to the present invention, even when there is a complicated bend in the pipe system, the air leak pipe is not blocked at the bend, and by feeding a heat medium into the air leak pipe, the bend The heating medium can flow through the leakage pipe, including the parts, and the heating medium spreads over the entire length of the leakage pipe. By heating the heat medium leaking from the leak pipe, the adhesive can be uniformly cured over the entire length of the pipe.

Therefore, there is no possibility that the adhesive will harden locally or that it will not harden sufficiently, and the hardening will not be uneven. Therefore, the pipe line and the lining material can be bonded quickly and reliably.

[Brief explanation of drawings]

FIG. 1 is a central vertical sectional view showing a state in which a heating medium is introduced into an air leakage pipe according to the present invention, and FIG. 2 is a central longitudinal sectional view showing a state in which a heating medium is introduced into an air leakage pipe by a conventional method. It is a front view. DESCRIPTION OF SYMBOLS 1... Pipeline, 2... Lining material, 5... Cylindrical fabric, 6... Covering layer, 7... Air leakage pipe.

Claims (1)

[Claims] 1 The lining material 2 is pressed onto the inner surface of the pipe line 1 via a reaction curing adhesive, and the lining material 2 is
A flexible air leakage pipe 7 formed by forming a synthetic resin coating layer 6 on the outer surface of the cylindrical fabric 5 and a large number of fine leakage holes in the coating layer 6 is inserted into the lining material 2. A gaseous heat medium is pressurized into the leakage pipe 7 to cause the heat medium to leak out from the leakage hole while maintaining the state in which the lining material 2 is in pressure contact with the inner surface of the pipe line 1 by applying fluid pressure to the leakage pipe 7. A method for lining a pipe line, characterized in that the lining material 2 is bonded to the pipe line 1 by promoting curing of the adhesive using the heat of the heating medium.