JPH0361791A - Repairing method for pipe - Google Patents

Abstract

PURPOSE:To simply repair the broken position of a pipe in a short time by pressing the porous section of a repairing sheet impregnated with a thermosetting synthetic resin adhesive to a pipe wall to be repaired, then heating a planar heating element, and hardening the synthetic resin. CONSTITUTION:Flexible electric wires are woven on both side edge sections of a woven fabric, a conducting paint is coated, and a planar heating element stuck with vinyl chloride films on both faces is formed. A mat-shaped nonwoven fabric made of glass fibers and polyester fibers is laminated and stuck on one face with a synthetic rubber adhesive to form a repairing sheet. A thermosetting epoxy resin adhesive is impregnated on the nonwoven fabric portion of the repairing sheet, the nonwoven fabric portion is closely stuck on the inner wall face of a concrete sewer pipe with cracks, the repairing sheet is stuck on the whole inner wall face, and it is supported by a cylindrical rubber balloon from the inside. The planar heating element is excited and heated for about 1hr to harden the adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for repairing damaged parts of pipes such as sewer pipes buried underground.

(Prior Art) Underground pipes are deformed due to uneven earth pressure and may sometimes break, while sewer pipes may leak and cause further damage.

Conventionally, such damage to underground piping has been dealt with by digging back up from above ground, repairing the damaged area, and then backfilling. However, this method increases cost and man-hours,
Various methods have been proposed for repairing pipes from inside without digging up the pipes.

Among them, the method of sealing by leaking grouting agent from inside the pipe through the damaged part and solidifying the damaged part and the surrounding earth and sand outside the pipe consumes a large amount of materials but requires a lot of man-hours. Although it is economical as it requires a relatively small amount, it has the disadvantage that it takes a long time for the grout to solidify.

In response to this, a method has been proposed in which a tubular lining material made of thermosetting synthetic resin is introduced into the pipe, and hot water or the like is pressurized into the tube to press and harden the lining material onto the inner wall of the pipe. Although this method allows construction to proceed in a relatively short period of time, complete repair cannot be expected unless the diameter of the piping and tube match, and construction management is difficult as hot water must be reheated and circulated. Since it is not easy, it has the disadvantage that it is not economical for small-scale construction.

(Problems to be Solved by the Invention) Considering the above-mentioned shortcomings of the prior art, the present invention aims to provide a method that can easily and quickly repair damaged parts of piping.

(Means for Solving the Problems) The piping repair method of the present invention that can achieve the above-mentioned objects uses a repair sheet made by laminating a nonwoven fabric on one side of a flexible sheet heating element. The non-woven fabric part is impregnated with a thermosetting synthetic resin adhesive, and the repair sheet is pressed against the wall surface of the repaired area of the pipe so that the non-woven fabric part comes into close contact with the wall, and then the planar heating element is made to generate heat. It is characterized by curing the adhesive.

The repair sheet used in the method of the present invention has a base having essentially the same configuration as a conventionally known planar heating element, for example, each side edge has flexible parts. It may be configured by arranging electric wires and providing a flexible sheet-like conductive heating section between these electric wires. Then, a nonwoven fabric is bonded to one surface of such a substrate and laminated. The nonwoven fabric used here must be able to retain liquid impregnation, and in particular must not be attacked by a liquid thermosetting synthetic resin adhesive, and must not be damaged by the adhesive with the sheet heating element. It suffices if the material is free from scratches.

The thermosetting synthetic resin adhesive used in the present invention is
Any material that is liquid when used and can be impregnated into a nonwoven fabric, and can be thermoset and adhered to the piping to be treated is sufficient; for example, an appropriate material such as epoxy resin, urethane resin, or polyester resin may be selected. It can be used.

When repairing piping by the method of the present invention, a repair sheet is appropriately selected depending on the size and shape of the damaged area, and then a thermosetting synthetic resin adhesive is impregnated and held in the nonwoven fabric portion. The sheet prepared in this way is introduced into the pipe, and the non-woven fabric portion is brought into close contact with the area that requires repair, covering all the areas requiring repair. An appropriate method can be used, such as pressing the backing plate with a tool or the like.

If the area requiring repair extends around the entire circumference of the pipe, use a repair sheet that is longer than the circumference of the inner wall of the pipe and attach it so that the edges overlap. Preferably, a plurality of sheets may be successively joined and pasted so that their edge portions overlap each other.

In this way, when the repair sheet is pasted on the inner surface of the pipe and is compressed, electricity is applied to the planar heating element to generate heat.
The adhesive hardens and adheres to the inner wall surface of the pipe and fills the damaged part of the pipe, completing the repair.

Cracks and holes in the repaired pipes will be filled with synthetic resin adhesive, and a synthetic resin plate reinforced with non-woven fabric will be formed along the inner wall of the pipe, so that other unrepaired pipes can be repaired. This has the advantage of increasing the strength compared to the other parts. Furthermore, the planar heating element not only functions to heat the repaired area, but also functions as a template when curing the synthetic resin, and further functions as a coating material to protect the surface of the repaired area. This is effective in further extending the service life of the repaired area.

(Example) A planar heating element was prepared by weaving flexible electric wires into both side edges of a woven fabric having a width of about 1 m, applying a conductive paint thereto, and then adhering vinyl chloride films to both sides. And this one side is made of glass fiber and polyester fiber with a thickness of about 6 mm.
A repair sheet was obtained by laminating and adhering the matte nonwoven fabrics using a synthetic rubber adhesive.

The non-woven fabric part of this repair sheet is impregnated with a thermosetting epoxy resin adhesive, and the non-woven fabric part is brought into close contact with the inner wall surface of the cracked concrete sewer pipe, so that the repair sheet covers the entire circumference of the inner wall surface. was attached and supported from the inside with a cylindrical rubber balloon.

Next, electricity was applied to the planar heating element to heat it to about 60°0 and hold it for 1 hour to cure the adhesive.

After removing the balloon, immediately conduct a water leak test.
We confirmed that the cracks were completely repaired.

(Effects of the Invention) The pipe repair method of the present invention can repair damaged parts of buried pipes, etc. from the inside using a simple construction method, and is characterized by being economical regardless of the scale. .

Furthermore, since the surface of the repaired area is smooth and reinforced, it has the advantage that it is less likely to be damaged than an unrepaired area.

hand Continued Supplementary Positive book (spontaneous) December 22, 1999

Claims (1)

[Claims] A repair sheet made by laminating a nonwoven fabric on one side of a flexible planar heating element is impregnated with a thermosetting synthetic resin adhesive, and the nonwoven fabric is applied to the wall surface of the part of the pipe that requires repair. A method for repairing piping, which comprises pressing the repair sheet so that they are in close contact with each other, and then causing the planar heating element to generate heat to cure the adhesive.