JP2001009909A - Lining construction method for inner surface of pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make even a lining cylinder reduced in wall thickness expansible and deformable without bursting the same so as not to leave folding marks as wrinkles and to make it hard to generate folding marks in the parts of the lining cylinder inserted in an existing pipe along the bent pipe part thereof as wrinkles. SOLUTION: A lining cylinder B made of a thermoplastic resin folded in its diameter direction to be deformed is inserted in an existing pipe and deformed by the heating fluid S2 introduced into the lining cylinder under pressure so as to be expanded in its diameter to line the inner peripheral surface of the existing pipe. In this lining construction method of the inner surface of a pipe, the lining cylinder inserted in the existing pipe is heated and a pig 8 for expanding the diameter of the lining cylinder is inserted in the lining cylinder and the heating fluid is introduced into the lining cylinder to deform the same so as to expand the diameter thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a lining tube made of a thermoplastic resin, which has been folded and deformed in a radial direction, is inserted into an existing pipe, and the lining tube is expanded and deformed with a heating fluid press-fitted inside. The present invention relates to a pipe lining method for lining the inner peripheral surface of an existing pipe.

[0002]

2. Description of the Related Art In a conventional in-pipe lining method, an inner peripheral surface of an existing pipe is lined by expanding and deforming a folded and deformed lining cylinder only with a heating fluid pressed into the inside thereof.

[0003]

For this reason, in order to expand and deform the lining tube so that the fold marks do not remain as wrinkles, the heating fluid must be press-fitted with a high pressure.
In the case of a lining tube that is thin and has a low bending stiffness in the state of being folded and deformed, and therefore can be easily inserted into the existing pipe, there is a risk that the lining tube may burst at a place where the inner diameter is large such as a joint. is there. Further, as shown in FIG. 7, when a lining tube B which is provided with a bent portion 1 bent toward the inside of the tube body and folded and deformed is inserted into an existing tube A provided with a bent tube portion b, Bent tube part b
The lining tube portion B2 inserted along the curved portion b is bent along the curved tube portion b in a state of being pressed against the inner peripheral surface 20 on the side where the radius of curvature of the curved tube portion b is smaller. If the bent portion 1 is pressed in a state where the depth direction of the portion 1 is in contact with the inner peripheral surface 20 of the pressed portion, the bent portion 1 is difficult to expand, and when the diameter is expanded and deformed, the folding mark becomes wrinkled and tends to remain. The present invention has been made in view of the above circumstances, and even with a thin lining tube which is easy to insert into an existing pipe, there is no fear of rupture, and a diameter expansion deformation such that a folding mark does not remain as a wrinkle remains. Even when the lining tube is inserted into an existing pipe having a bent pipe portion and the diameter of the lining tube is expanded and deformed, the folding trace becomes a wrinkle in the lining tube portion inserted along the bent pipe portion. The purpose is to make it difficult to remain.

[0004]

According to a first feature of the present invention, a lining tube made of a thermoplastic resin, which is folded and deformed in a radial direction, is inserted into an existing pipe, and the lining tube is press-fitted inward. This is an in-pipe lining method for expanding and deforming the fluid with a fluid, and lining the inner peripheral surface of the existing pipe, by heating a lining pipe inserted into the existing pipe and inserting a pig for diameter expansion inside the pipe, and The point is that the diameter is expanded by the heated fluid. [Function] Since the lining tube inserted into the existing pipe is heated and the diameter-enlarging pig is inserted into the inside, the softened fold is forcibly pushed and expanded with the diameter-expanding pig, and the lining tube is heated by the heating fluid. To expand the diameter. [Effect] Accordingly, the lining cylinder can be expanded and deformed without pressurizing the heating fluid at a high pressure as in the related art, so that even a thin lining cylinder which can be easily inserted into an existing pipe can burst. Without fear, it can be expanded and deformed so that the fold marks do not remain as wrinkles, and the fold can be forcibly pushed and expanded with the expanding pig, so the existing pipe with a bent pipe part is provided. Even when the lining tube is inserted into the tube and the diameter of the lining tube is expanded, it is difficult for the lining tube portion inserted along the bent tube portion to remain as a wrinkled folding mark.

A feature of the invention according to claim 2 is that the diameter-enlarging pig is mounted inside from one end side of the lining cylinder, and the heating fluid is pressed into the inside of the lining cylinder from one end side thereof. . [Operation] The diameter-expanding pig mounted inside the lining cylinder can be moved toward the other end of the lining cylinder by the pressure of the diameter-enlarging heating fluid press-fitted from one end of the lining cylinder. [Effect] By using the heating fluid for expanding and deforming the lining cylinder, the diameter-enlarging pig can be moved along the inside of the lining cylinder, and the operation can be simplified.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, portions denoted by the same reference numerals as those of the conventional example indicate the same or corresponding portions. FIG. 1 shows an example of an existing pipe, in which an inner peripheral surface is lined with a lining tube B in order to repair or prevent a gas leak of an existing city gas metal pipe A buried underground which is an example of an existing pipe. 1 shows a lining structure of a certain city gas pipe A, wherein the pipe A is provided with a straight pipe part a and a bent pipe part b having an inner diameter larger than the straight pipe part a. The lining tube B is extruded with a medium-density polyethylene resin as an example of a thermoplastic resin.

FIG. 2 shows the lining tube B before the diametrically expanding deformation, in which a bent portion 1 is formed at one place by bending a polyethylene No. 3 pipe for gas (JIS) inward along the longitudinal direction. The lining tube B, which has been folded and deformed in the radial direction in advance, is inserted into the pipe A, and expanded and deformed with steam as a heating fluid press-fitted inside the lining cylinder B. The peripheral surface is lined.

The in-pipe lining method for inserting the folded and deformed lining cylinder B into the pipe A over a predetermined lining section and lining the inner peripheral surface thereof will be described with reference to FIGS. I do. As shown in FIG. 3 (a), at both ends of the lining section, the first pit D1 and the second pit D2 are excavated, and the lining tube B that is folded and deformed is wound around the reel 2 and the inside of the lining tube B. A work vehicle 5 equipped with a boiler 4 for supplying steam through a steam supply pipe 3 is made to stand by near a first pit D1, and a work vehicle 7 provided with a winch 6 is made to stand by near a second pit D2. , D2, the pipe A exposed is cut, and a towing wire W is inserted therethrough using a wire passing tool or the like, and one end of the towing wire W is connected to the take-up drum of the winch 6 and the other end thereof. Is connected to the tip of the lining tube B wound on the reel 2.

The lining tube B is wound around a reel 2 with its winding side base communicating with the steam supply pipe 3 so as to be able to be fed out to the reel 2. The lining tube B is supplied by the steam supplied through the steam supply pipe 3. While heating, wind the tow wire W by driving the winch 6,
The pipe is drawn into the pipe A, and the lining tube B is inserted through the entire length of the pipe A in the lining section as shown in FIG.

Next, the both ends of the lining tube B are cut, and the ends thereof are expanded in a substantially circular shape, and as shown in FIG. 3 (c), a first end for pig insertion is cut into the cut end on the first pit D1 side. 1 jig C1
At the same time, a second jig C2 for inserting a pig is attached to the cut end on the second pit D2 side. As shown in FIG. 4 (a), the first jig C1 and the second jig C2 for inserting the pig are provided in a cylindrical container 9 for accommodating the pig 8 for expanding the diameter.
An extruding tool 10 for manually pushing out the inside diameter-enlargement pig 8 from the outside toward the lining cylinder B side, and a steam inlet for introducing steam from the lining cylinder B side to the storage position of the diameter-enlargement pig 8 The end of the cylindrical container 9 on the opening side is tightly connected and fixed to the lining tube B with a band 12 in an airtight manner.

At the end of the lining tube B on the first pit D1 side, a first jig C1 accommodating a diameter-enlarging pig 8 in a cylindrical container 9 is attached, and the lining on the second pit D2 side is provided. At the end of the tube B, there is provided a second
Attach the jig C2 and install the steam inlet 1 of the first jig C1.
1, the steam supply pipe 14 of the boiler 13 is connected to the steam supply port 14 of the boiler 13 and the steam inlet 11 of the second jig C2.

Next, the steam inlet 11 of the first jig C1
The inside of the lining tube B is set at 0.
While pressurizing to about 5 to 0.6 kgf / cm ² , the outer surface temperature of the pipe A is set to 85 ° C. over the entire length of the lining section.
After heating to about 86 ° C., as shown in FIG. 4B, the expanding pig 8 in the cylindrical container 9 is extruded by the extruding tool 10, and from one end side of the lining tube B to the inside thereof. Installing.

Next, as shown in FIG. 5A, the first jig C
The steam S2 of about 130 ° C., which was press-fitted into the lining cylinder B from the steam inlet 11 of the first, the inside of the lining cylinder B closer to the first jig C1 than the diameter-enlarging pig 8 was 1.2 to 1.5 k.
gf / cm ² , the pressure and the diameter of the pig 8
With the differential pressure from the pressure that decreases with the temperature decrease in the lining cylinder B on the second jig C2 side, the diameter-enlarging pig 8 is moved toward the second jig C2 while the lining cylinder B is moved. While being inserted inside, the lining tube B is expanded and deformed, and as shown in FIG.
Then, the steam is introduced into the second cylindrical container 9 to stop the introduction of steam from the steam inlet 11 of the first jig C1.

Next, as shown in FIG. 6A, the second jig C
6 is pushed out by an extruder 10 and attached from one end side of the lining tube B to the inside thereof. As shown in FIG. Tool C2
The steam S3 of about 130 ° C., which was press-fitted into the lining tube B from the steam introduction port 11 of the above, 1.2-1.5 kg in the lining tube B closer to the second jig C2 than the diameter-enlarging pig 8.
f / cm ² , the pressure and the diameter of the pig 8
Of the lining cylinder B while moving the diameter-enlarging pig 8 toward the first jig C1 with a pressure difference from the pressure that decreases with the temperature decrease in the lining cylinder B on the first jig C1 side. At the same time, the lining tube B is expanded and deformed so that the pig 8 for expanding the diameter is inserted into the cylindrical container 9 of the first jig C1.

Next, although not shown, air for cooling is supplied to the steam inlet 11 of the second jig C2 instead of the steam S3, so that the inside of the lining tube B is 1.2 to 1.5 kgf.
The lining tube B was cooled while maintaining the order of / cm ^2,
As shown in FIG. 1, after being mounted on the inner peripheral surface of the pipe A in a state where the folding mark is wrinkled and hard to remain over the entire length of the lining tube B, the first jig C1 and the second jig C2 are provided. From the lining tube B.

[Other Embodiments] In the in-pipe lining method according to the present invention, the lining cylinder inserted into the existing pipe is preliminarily expanded with a heating fluid press-fitted inside, and then a diameter-expanding pig is inserted inside the lining pipe, and the lining cylinder is deformed with the heating fluid. Is also good. 2. In the in-pipe lining method according to the present invention, the diameter-enlarging pig attached to the inside of the lining tube may be pulled by a wire or the like, and inserted through the entire length of the lining tube. 3. The in-pipe lining method according to the present invention may use a lining tube made of a thermoplastic resin in which a plurality of circumferential portions are radially folded and deformed. 4. In the in-pipe lining method according to the present invention, the lining cylinder may be expanded and deformed with a heated liquid such as hot water into which the lining tube is press-fitted. 5. In the in-pipe lining method according to the present invention, the lining cylinder whose diameter has been deformed may be bonded to the inner peripheral surface of an existing pipe. 6. The in-pipe lining method according to the present invention may use a lining tube made of a thermoplastic resin other than a polyethylene resin, such as a polyolefin resin. 7. In the pipe lining method according to the present invention, the inner peripheral surface of an existing liquid pipe such as a water pipe or a sewer pipe other than the gas pipe may be lined.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a lining structure.

FIG. 2 is a perspective view of a lining cylinder before diameter expansion deformation.

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

FIG. 4 is an explanatory view of a pipe lining method.

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

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

FIG. 7 is an explanatory view of a conventional in-pipe lining method.

[Explanation of symbols]

 8 Pig for expanding diameter A Existing pipe B Lining cylinder S2 Heated fluid S3 Heated fluid

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Claims (2)

[Claims] A lining tube made of a thermoplastic resin, which has been folded and deformed in a radial direction, is inserted into an existing pipe, and the lining cylinder is expanded and deformed by a heating fluid press-fitted inside, thereby forming an inner peripheral surface of the existing pipe. An in-pipe lining method for heating a lining tube inserted into the existing pipe, inserting a diameter-expanding pig inside the lining pipe, and expanding and deforming the pipe with the heating fluid. 2. The in-pipe lining method according to claim 1, wherein the diameter-enlarging pig is mounted inside from one end of the lining tube, and the heating fluid is pressed into the inside of the lining tube from one end thereof.