JP2000094520A - Method for lining inside of pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of an existing pipe while the improvement of work efficiency being attempted. SOLUTION: In a method for lining the inside of a pipe in which while a lining cylinder A being inserted into an existing pipe B, the inner and outer surfaces of the lining cylinder are inverted in turn from the tip side in the insertion direction, and the inner surface B1 of the existing pipe is lined, while the lining cylinder of a thermoplastic resin is being heated and softened, the inner and outer surfaces of the cylinder are inverted in turn from the tip side in the insertion direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe lining for lining the inner peripheral surface of an existing pipe by inserting the lining pipe into an existing pipe and inverting the inner and outer surfaces of the lining pipe in order from the front end side in the insertion direction. Concerning the construction method.

[0002]

2. Description of the Related Art Conventionally, in the above-mentioned in-pipe lining method, a lining tube which can be freely bent and deformed at room temperature and is capable of self-holding its deformed state is radially folded and deformed at room temperature, and is inserted into an existing pipe. In order to maintain the shape of the inverted lining tube along the inner peripheral surface of the existing pipe in order to maintain the shape of the inverted lining cylinder in the inner circumference of the existing pipe, Glued to the surface.

[0003]

Therefore, in order to improve workability by easily reversing the inner and outer surfaces of the lining tube which is folded and deformed in the radial direction, it is necessary to use a thin lining tube. There is a drawback that it is difficult to increase the durability of the existing pipe, and conversely, if a thick lining pipe is used to increase the durability of the existing pipe, it will be difficult to reverse the inner and outer surfaces of the lining pipe, so workability There is a drawback that it is difficult to improve.

Further, in order to bond the lining cylinder to the inner peripheral surface of the existing pipe, a preparation work such as applying an adhesive in advance to the inner peripheral side of the lining cylinder before reversing is necessary. There is a disadvantage that it is difficult to improve workability.

The present invention has been made in view of the above circumstances, and has as its object to improve the durability of existing pipes while improving workability.

[0006]

According to a first feature of the present invention, the lining tube is inserted into the existing tube while the inner and outer surfaces of the lining tube are sequentially inverted from the leading end side in the insertion direction. Is an in-pipe lining method for lining the inner peripheral surface of the pipe, wherein the inner and outer surfaces are sequentially inverted from the front end side in the insertion direction while the lining cylinder formed of a thermoplastic resin is heated and softened.

In other words, since the lining tube formed of a thermoplastic resin that cures at room temperature is heated and softened, its inner and outer surfaces are sequentially inverted from the front end side in the insertion direction. It can be easily inverted.

Accordingly, the durability of the existing pipe can be improved with the thick lining cylinder while improving the workability. In particular, according to the pipe lining method according to the present invention,
In addition to rehabilitating the existing pipe, by making the lining pipe thick enough, the lining pipe itself can secure the same strength as the new pipe.
The existing pipe can also be renewed using the lining pipe as a new pipe.

A second aspect of the present invention is characterized in that heated and pressurized steam is supplied between a lining tube portion before inversion inserted into the existing pipe and a lining tube portion after inversion,
The point is that, while softening the lining cylinder, the inner and outer surfaces thereof are sequentially inverted from the front end side in the insertion direction.

That is, while the lining tube is softened by the heating and pressurized steam supplied between the lining tube portion before inversion inserted into the existing pipe and the lining tube portion after inversion, the inner and outer surfaces of the lining tube are inserted in the insertion direction. Since the inversion is performed in order from the side, after the inverted lining tube is deformed into a shape along the inner peripheral surface of the existing pipe, the temperature of the lining tube can be returned to normal temperature and hardened.

Therefore, it is possible to maintain the shape of the lining cylinder along the inner circumference of the existing pipe without bonding the lining cylinder to the inner circumference of the existing pipe. Preparation work such as applying an adhesive in advance on the inner peripheral side of the lining cylinder is not necessary, and workability can be further improved.

In particular, a lining tube having a diameter smaller than the inner diameter of the existing pipe is folded flat in the radial direction, and is inverted while being inserted into the existing pipe, and the inverted lining cylinder is shaped along the inner peripheral surface of the existing pipe. Therefore, the workability can be more easily improved also in this point because the heat-pressurized steam can be used to expand in the radial direction.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] FIG. 1 shows a lining of an inner peripheral surface B1 of a gas pipe B in order to repair or prevent a gas leak caused by corrosion of a gas pipe B buried underground, which is an example of an existing pipe. The lining structure of the gas pipe B lined with the cylinder A is shown.

The lining tube A is formed of a polyethylene resin (crosslinked polyethylene obtained by crosslinking polyethylene having a density of 0.92 g / cm ³ and a melt index of 1.0 g / 10 minutes (method according to JIS K6760)) which is an example of a thermoplastic resin. Both ends of the inner peripheral surface B of the gas pipe B are connected to the inner peripheral surface B of the gas pipe B by the expanding-diameter urging ring C mounted inside the lining cylinder A.
1 to seal between the lining tube A and the gas pipe B.

Further, the lining tube A before being attached to the gas pipe B has an outer diameter substantially equal to the inner diameter of the gas pipe B in a state where the inner and outer surfaces are reversed in the gas pipe B as described later. The lining tube A before being attached to the gas pipe B is heated and softened, and is folded in the radial direction as shown in FIG. Then, as described later, the folded lining tube A
Is wound around a drum 2 so that the end sealed by the clip 1 is finally fed out, and the drum 2 is supported in a casing 3.

Hereinafter, a pipe lining method according to the present invention will be described with reference to FIGS.

As shown in FIG. 3, the section T
Pits D1 and D2 are excavated at both ends of
The gas pipe B is opened in D2, and the casing 3 is temporarily placed in one pit D1. The drum 2 is wound around a lining tube A having a length corresponding to the length of the lining target section T.

Next, the pay-out end of the lining tube A is heated and softened by heating steam, and as shown in FIGS. 4 and 5, the inner and outer surfaces of the soft-feed end are manually inverted. Then, the casing 3 is temporarily fixed to an end of the gas pipe by a jig 4, and the casing 3 is air-tightly connected to an open end of the gas pipe B by a connecting portion 3 a provided on the casing 3 as shown in FIG.

Next, as shown in FIGS. 7 and 8, a heated and pressurized steam P is supplied into the casing 3 and the lining tube portion before the inversion inserted into the gas pipe B and the lining tube portion after the inversion. In the state where the heated and pressurized steam P is supplied, the lining tube A wound around the drum 3 is softened by the heat of the steam P, and the softened lining tube A is compressed by the pressure of the steam P. The lining tube A is inserted into the gas pipe B, and the inner and outer surfaces of the lining tube A are sequentially inverted from the distal end in the insertion direction.

Then, as shown in FIG. 9, the lining tube A is inverted over the entire length of the section T to be lined, and the lining tube A is deformed into a shape along the inner peripheral surface of the gas pipe B, and then naturally cooled. Then, the end of the lining tube A, which is sealed with the clip 1, is cut in accordance with the opening end of the gas pipe B, and the casing 3 and the jig 4 are removed, as shown in FIG. Gas pipe B with enlarging ring C
Lining cylinder A and gas pipe B
Seal between

[Second Embodiment] As shown in FIG. 10, a wire 5 is inserted inside a lining tube A folded radially, and one end of the wire 5 is fixed with a clip 1 so that a drum 2 is fixed together with the lining tube A. When the lining tube A is inserted into the gas pipe B and the inner and outer surfaces thereof are turned over, the wire 5 is pulled in the insertion direction as shown in FIG. The inner and outer surfaces of the lining tube A may be reversed while the lining tube A is inserted by the pulling force of the wire 5. Other configurations are the same as those of the first embodiment.

[Other Embodiments] <1> The in-pipe lining method according to the present invention is intended not only to rehabilitate the existing pipe, but also to ensure the thickness of the lining pipe so that the lining pipe itself can secure the same strength as the new pipe. May be made sufficiently thick and the lining tube may be used as a new pipe to replace an existing pipe. <2> The in-pipe lining method according to the present invention is to soften a lining pipe made of a thermoplastic resin having a smaller diameter than the inner diameter of an existing pipe, fold it flat in the radial direction, and invert the lining pipe while inserting it into the existing pipe. Then, the inverted lining cylinder may be radially expanded with heated and pressurized steam and then naturally cooled so that the shape of the inverted lining cylinder can be maintained along the inner peripheral surface of the existing pipe. <3> The pipe lining method according to the present invention may be applied not only to existing gas pipes but also to existing water pipes and sewer pipes. <4> In the pipe lining method according to the present invention, in addition to the polyethylene resin as the thermoplastic resin, a lining cylinder formed of a thermoplastic polyester resin such as polyethylene terephthalate (PET) may be used. The type of the plastic resin is not particularly limited. <5> The in-pipe lining method according to claim 1, wherein an adhesive is applied in advance to the inner peripheral side of the lining cylinder before inversion,
The lining cylinder may be cured to a shape along the inner peripheral surface of the existing pipe by cooling while the outer peripheral face of the lining cylinder after inversion is adhered to the inner peripheral face of the existing pipe with the adhesive.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part.

FIG. 2 is a perspective view of a main part.

FIG. 3 is an explanatory view of a lining method.

FIG. 4 is an explanatory view (perspective view) of a lining method.

FIG. 5 is an explanatory view of a lining method.

FIG. 6 is an explanatory view of a lining method.

FIG. 7 is an explanatory view of a lining method.

FIG. 8 is an explanatory view of a lining method.

FIG. 9 is an explanatory view of a lining method.

FIG. 10 is a perspective view of a main part showing a second embodiment.

FIG. 11 is an explanatory view of a lining method showing a second embodiment.

[Explanation of symbols]

 A Lining cylinder B Existing pipe B1 Inner peripheral surface P Heated and pressurized steam

Claims (2)

[Claims] 1. An in-pipe lining method in which a lining pipe is inserted into an existing pipe, and the inner and outer surfaces of the lining pipe are sequentially inverted from the tip end side in the insertion direction to line the inner peripheral face of the existing pipe. An in-pipe lining method in which the lining tube formed of a plastic resin is heated and softened while its inner and outer surfaces are sequentially inverted from the front end side in the insertion direction. 2. A heating and pressurizing steam is supplied between a lining tube portion before inversion inserted into the existing pipe and a lining tube portion after inversion to soften the lining tube while removing the inner and outer surfaces thereof. 2. The in-pipe lining method according to claim 1, wherein the pipe lining is reversed in order from the distal end in the insertion direction.