JP2000343607A - Technique for lining inside of pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily enlarge diameter and deform a lining pipe so that a folding trace does not remain as a wrinkle in such a state that the part of the lining pipe inserted into the part easily undergoing a large enlargement of diameter and deformation as compared with the inside diameter of the straight pipe part of an existing pipe is hardly ruptured. SOLUTION: In the technique for lining the inside of a pipe, a lining pipe B made of thermoplastic resin is folded in the direction of diameter, deformed and inserted into an existing pipe A and enlargement of diameter and deformation of the lining pipe are performed by a heated fluid forcibly fed to the inside and lining on the inner peripheral face of the existing pipe is performed. Enlargement of diameter and deformation of the lining pipe inserted into the existing pipe are performed by the heated fluid while regulating elongation in the peripheral direction.

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, a bent pipe section or a straight pipe section in which a straight pipe portion is connected to an existing pipe by an elbow having an inner diameter larger than the inner diameter of the straight pipe portion. Even if the connecting part connected by a sleeve with an inner diameter larger than the inner diameter of the lining is provided, there is no particular restriction on the amount of radial expansion deformation of the bent pipe part or the lining tube part inserted in the connecting part. The diameter is expanded by the pressurized heating fluid.

[0003]

In the in-pipe lining method, it is desirable that the lining cylinder be expanded and deformed so that the folding traces do not remain as wrinkles. However, according to the above-described conventional in-pipe lining method, when the folded lining tube is expanded and deformed with a high-pressure heating fluid so that the fold mark does not remain as a wrinkle, as shown in FIG. In addition, although the lining cylindrical portion B1 inserted into the straight pipe portion a is restricted in its diameter expansion deformation by contact with the inner peripheral surface of the straight pipe portion a, the inner diameter of the elbow 1 and the sleeve 2 is smaller than that of the straight pipe portion a. The lining tube portion B2 inserted into the bent tube portion b or the lining tube portion B3 inserted into the connection portion c is larger than the inner diameter, and the lining tube portion B3 is greatly expanded and deformed as compared with the lining tube portion B1 inserted into the straight tube portion a. Since the thickness of the lining tube B is easily reduced and the lining tube B is liable to be ruptured, the lining tube B has a disadvantage in that it is difficult to expand and deform the lining tube B so that the folded trace does not remain as wrinkles. In particular, since the lining tube portion B2 inserted into the bent tube portion b before the diameter expansion and deformation is applied to the tube wall on the side where the radius of curvature is larger, the pulling force acts in the tube longitudinal direction, so that the wall thickness is increased while the wall thickness is reduced. There is a problem that the diameter is easily deformed and the possibility of rupture is increased. The present invention has been made in view of the above situation, and in a state in which the lining tube portion inserted into a portion of the existing tube that is easily expanded and deformed to be larger than the inner diameter of the straight tube portion is less likely to burst, and the lining tube is An object of the present invention is to make B easily expandable and deformed so that its folding mark does not remain as wrinkles.

[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. An in-pipe lining method for lining the inner peripheral surface of the existing pipe by expanding and deforming the pipe with a fluid, wherein the lining pipe inserted into the existing pipe is expanded with the heating fluid while restricting the elongation in the circumferential direction. The point is to deform the diameter. [Operation] The lining tube inserted into the existing pipe is expanded and deformed by the heating fluid while restricting its circumferential expansion, so that it expands greatly compared to the inner diameter of the straight pipe section such as a bent pipe section or a connection section. Even if the lining tube portion inserted in the portion that is easily deformed in diameter is expanded and deformed by a high-pressure heating fluid, the amount of expanded deformation of the lining tube portion can be regulated. [Effect] Since the amount of diametric deformation of the lining tube portion inserted into a portion where large diametric deformation easily occurs can be regulated,
The lining tube B is less likely to become thinner, and in particular, the lining tube portion inserted into the bent tube portion is less likely to become thinner. It is easy to expand and deform so that the fold marks do not remain as wrinkles.

According to a second feature of the present invention, the lining tube inserted into the existing pipe is formed of a weft along a circumferential direction of the tube and a warp along the longitudinal direction of the tube, the expansion being smaller than that of the lining tube. In other words, the lining cylinder is made to penetrate into a heat-resistant net or cloth tubular body having heat resistance to regulate the circumferential extension of the lining cylinder. [Action] Without special processing on the lining cylinder,
The expansion in the circumferential direction of the lining cylinder part inserted into a part that is easily expanded and deformed larger than the inner diameter of the straight pipe part when expanding and deforming,
It can be regulated by a weft thread along the circumferential direction of the heat-resistant net or cloth cylinder. [Effect] A lining tube similar to the conventional one can be used, and, for example, when lining the inner surface of an existing pipe only in a straight pipe portion where there is no large-diameter deformable portion such as a bent pipe portion or a connection portion, Efficient construction can be performed as necessary, such as construction without using a body.

A feature of the invention according to claim 3 is that the warp is formed of a yarn having a larger elongation than the weft. [Operation] While the circumferential extension of the lining cylinder is regulated by the weft yarn, the extension in the cylinder longitudinal direction can be allowed. [Effect] Since it is possible to restrict the elongation in the circumferential direction of the cylinder while allowing the deformation along the longitudinal direction of the cylindrical wall of the side of the lining cylindrical portion inserted into the curved pipe portion where the radius of curvature is large, the radius of curvature is small. Wrinkles along the circumferential direction of the tube are not easily generated on the side wall of the tube, and the cross-sectional shape of the lining tube in the bent tube portion is hardly flattened, so that the flow path cross-sectional area can be easily secured.

[0007]

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. The lining structure of a certain city gas pipe A is shown. The pipe A is provided with a bent pipe portion b connecting the straight pipe portions a with the elbow 1 and a connection portion c connecting the straight pipe portions a with the sleeve 2. 2 has an inner diameter larger than the inner diameter of the straight pipe section a.
The lining tube B is extruded with a medium-density polyethylene resin as an example of a thermoplastic resin, and is inserted into the tubular body 3 made of heat-resistant net and attached to the inside of the pipe A. is there.

FIG. 2 shows a lining tube B mounted inside a pipe A in a state where the pipe A is removed. The lining tube B has a cylindrical shape having substantially the same diameter over the entire length. It is mounted in a state where its shape is restrained by the cylindrical body 3. The tubular body 3 is composed of a natural fiber such as cotton and hemp, which has a smaller elongation than the lining tube B, a synthetic fiber such as vinylon fiber and aramid fiber, a carbon fiber, a glass fiber and the like. And a net formed by knitting with a warp yarn 6 extending along the longitudinal direction of the tube made of urethane fiber, polyethylene fiber, polypropylene fiber, or the like having a greater elongation than the weft yarn 4, and having a circumferential length of a straight pipe portion a. The length is substantially the same as the length of the inner circumferential side in the circumferential direction. FIG. 3 shows the lining tube B before the diametrically expanding deformation. The lining tube B is folded and deformed in the radial direction in advance and enters the cylindrical body 3.

The lining tube B is inserted into the pipe A over a predetermined lining section, and the lining tube B is expanded and deformed with steam as a heating fluid press-fitted inside, so that the inner peripheral surface of the pipe A is deformed. The in-pipe lining method for lining will be described with reference to FIGS. As shown in FIG. 4A, pits D1 and D2 are provided at both ends of the lining section.
A work vehicle 11 equipped with a reel 4 wound around a lining tube B folded and deformed and a boiler 10 for supplying steam through a steam supply pipe 9 inside the lining tube B is placed near one pit D1. While waiting, the work vehicle 8 having the winch 7 is moved to the other pit D
2 Wait near. Then, the pipe A exposed in each of the pits D1 and D2 is cut, and the towing wire W is inserted using a wire passing tool or the like, and one end of the towing wire W is connected to the winding drum of the winch 7. At the same time, the other end is connected to the end of the lining tube B wound on the reel 4 together with the cylindrical body 3.

The lining tube B is wound on the reel 4 so as to be able to be fed out to the reel 4 with the end portion on the feeding side hermetically closed, and the base portion on the winding side is communicated with the steam supply pipe 9. . Then, while heating the lining tube B with steam supplied through the steam supply pipe 9,
The towing wire W is taken up by driving the winch 7, and the lining tube B is pulled into the pipe A together with the tubular body 3 as shown in FIG.
As shown in (b), the lining tube B is inserted through the entire length of the pipe A in the lining section together with the tubular body 3.

Next, steam at a temperature of about 130 ° C. is supplied to the inside of the lining cylinder B through the steam supply pipe 9 and pressurized to a pressure of about 1.7 kgf / cm ² , and FIG.
When the lining tube B is expanded and deformed and then cooled in a pressurized state, as shown in FIGS. 1 and 2, the lining tube portion B1 inserted into the straight pipe portion a is expanded in diameter. The amount of deformation is regulated by the contact with the inner peripheral surface of the pipe, and the folded trace is attached along the inner peripheral surface of the pipe without wrinkling and remains, and the straight pipe section a such as a bent pipe section b or a connection section c is formed. Lining tube part B inserted in a part that is larger than the inner diameter and is easily expanded and deformed
2, B3, the elongation in the circumferential direction is restricted by the weft thread 5 along the pipe circumferential direction of the tubular body 3, the amount of diameter expansion deformation is regulated, and as a result, the elbow 1 and the inner peripheral surface of the sleeve 2 Gap 1 between
It is mounted in a state where the fold marks do not remain as wrinkles across the two. Further, the lining tubular portion B2 inserted into the bent pipe portion b allows the warp 6 having a large elongation to deform the cylindrical wall 13 having a large radius of curvature along the longitudinal direction of the tube wall 13 while allowing the warp 6 to expand in the circumferential direction of the cylinder. Wrinkles along the circumferential direction of the tube wall 14 on the side with the smaller radius of curvature are less likely to occur, and the cross-sectional shape of the lining tube B in the bent tube portion b is less likely to be flat, and the flow path is cut off. Easy to secure area.

[Other Embodiments] The in-pipe lining method according to the present invention comprises a natural fiber such as cotton or hemp, which has a smaller elongation than a lining tube, a synthetic fiber such as vinylon fiber or aramid fiber, a carbon fiber, a weft along a circumferential direction of a glass fiber or the like, The lining tube is inserted into a cloth tube woven with a warp yarn extending along the length of the tube, which is made of urethane fiber, polyethylene fiber, polypropylene fiber, etc., which has greater elongation than the weft, and regulates the circumferential expansion of the lining tube. May be. 2. The in-pipe lining method according to the present invention comprises a mesh or cloth tubular member formed by arranging a weft having a smaller elongation than a lining tube in a spiral shape along the circumferential direction of the tube and forming the weft and a warp along the longitudinal direction of the tube. Put the lining tube into your body,
The extension of the lining cylinder in the circumferential direction may be restricted. 3. In the in-pipe lining method according to the present invention, a weft yarn having a smaller elongation than the lining tube is bonded in advance in a spiral shape to the peripheral surface of the folded and deformed lining tube in a circumferential direction of the tube, and the lining is formed by the weft yarn. The extension of the cylinder in the circumferential direction may be restricted. 4. In the in-pipe lining method according to the present invention, a weft yarn having a smaller elongation than the lining tube is embedded in advance in a spiral shape along the circumferential direction of the tube within the thickness of the folded and deformed lining tube. The extension of the cylinder in the circumferential direction may be restricted. 5. 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. 6. 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. 7. 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. 8. 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. 9. 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 showing a mounted state of a lining tube.

FIG. 3 is a perspective view of the lining cylinder before the expansion deformation.

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 conventional pipe lining method.

[Explanation of symbols]

 A Existing pipe B Lining cylinder 3 Cylindrical body 5 Weft 6 Warp

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B29K 23:00 105: 08 B29L 9:00 23:00 F term (Reference) 3H025 EA01 EB23 EC03 ED01 3H111 AA02 BA15 CC02 CC22 DA11 DA26 DB27 4F211 AD16 AG03 AG08 AG12 AM32 SA13 SC03 SD04 SD11 SD23 SG01 SH18 SJ01 SP15 SP21

Claims (3)

[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. A pipe lining method in which a lining tube inserted into the existing pipe is expanded and deformed by the heating fluid while restricting circumferential expansion. 2. A heat-resistant net formed by forming a lining tube inserted into the existing pipe with a weft yarn extending along the circumferential direction of the tube and a warp yarn extending along the longitudinal direction of the tube, the elongation being smaller than the lining tube. 2. The in-pipe lining method according to claim 1, wherein the lining pipe is penetrated into a cloth body to restrict circumferential expansion of the lining pipe. 3. The in-pipe lining method according to claim 2, wherein the warp yarn is constituted by a yarn having a larger elongation than the weft yarn.