JP2712050B2 - Inversion lining method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reversing lining method applicable to sewerage, waterworks, oil supply pipes and any other existing pipes, and more particularly to an improvement in the adhesion of synthetic resin pipes to existing pipes. is there.

[Prior art] In recent years, for the purpose of reinforcing the strength of existing pipes such as sewers and waterworks, countermeasures against corrosion, countermeasures against water leakage and infiltration, and improvement of flow rate, etc., a synthetic resin is lined on the inner surface of an existing pipe, or a synthetic resin is The reversal lining method of forming is in the limelight.

For example, the method disclosed in Japanese Patent Publication No. 55-43890 and Japanese Patent Application Laid-Open No. 64-85738 discloses a method in which a needle felt layer is impregnated with a liquid thermosetting resin such as epoxy or polyester, and a lining material is subjected to fluid pressure in an existing pipe. And then press the inner lining material against the inner surface of the existing pipe by fluid pressure.
This is a method of curing a thermosetting resin and lining a synthetic resin on the inner surface of an existing pipe.

The method disclosed in JP-A-64-16633, JP-A-64-16634, or JP-A-63-285395 discloses a method in which a small-diameter thermoplastic plastic pipe is inserted into an existing pipe. In this method, a thermoplastic pipe is heated and pressurized from the inside to expand it, and is brought into close contact with the inner surface of the existing pipe.

Furthermore, in the method disclosed in European Patent EPO184366A1, a thin synthetic resin plate wound spirally is inserted into an existing pipe while being spirally formed by a winding machine (tube making machine), and then the lining material and the existing pipe are inserted. The space is filled with grout material.

[Problems to be Solved by the Invention] In the lining material used in the conventional reversing method represented by Japanese Patent Publication No. 55-43890, when the liquid thermosetting resin impregnated in the needle felt layer is reversed in the existing pipe. It moves in the felt layer by uneven pressing force acting in the circumferential direction of the inversion surface. For this reason, a difference occurs in the resin impregnation amount in the cross-sectional direction of the felt layer, and there is a disadvantage in that in addition to the thickness variation, the strength varies.

In particular, when a long lining material is used, it is necessary to wind or fold it after the impregnation process in order to store a soft lining material impregnated with the liquid resin. At this time, the thickness of each portion of the lining material varies due to the difference in its own weight or the pressing force, and an environmental pressure difference is applied to the liquid resin. When the synthetic resin pipe is formed of the lining material in such a state, the thickness and the strength also vary.

Further, it is very difficult to impregnate the liquid resin uniformly over the entire length of the flexible pack, and usually, a variation of ± 15% occurs, and a uniform synthetic resin tube cannot be formed.

Also, if there are gaps such as gaps, gaps, cracks, etc. in the existing pipes' technical pipes and joints, the liquid resin around these gaps oozes into the gaps due to the pressing force of the existing pipes after reversal, and In addition to the decrease in strength, the liquid resin has a disadvantage that the viscosity decreases before gelation due to heating and flows out together with the underground infiltration water, resulting in a porous impregnated layer, which significantly reduces the strength.

In addition, the lining material impregnated with the thermosetting resin is inverted and then heat-cured and molded, but the total time of heating time and cooling time during heat curing is, for example, 300 mm in diameter, 6 mm thick lining material. It takes about 15 hours when using polyester resin. In addition, even a quick-drying epoxy resin takes about 6 to 8 hours, and has a disadvantage that the working time is long. This is also due to the fact that heat is stored in the existing pipe and surrounding soil during the long heating and holding period, and the cooling rate becomes slow.

Further, as described in JP-A-64-16633, JP-A-64-16634 or JP-A-63-285395, a thermoplastic resin processed into a smaller cross-sectional shape than the existing pipe diameter is used. In order to heat, soften, and expand the pipe, the difference in elongation under the same pressure due to the difference in resin temperature is large, and when the pipe is heated, it becomes in an indefinite state and has a small self-expanding force. Therefore, it is necessary to uniformly heat both the circumferential direction and the longitudinal direction of the existing pipe and the resin pipe under the same pressure. However, in practice, there are disadvantages in that the heating temperature varies, wrinkles occur in the resin pipe, the pipe thickness varies, and a gap is formed between the pipe and the existing pipe.

Furthermore, if only the thermoplastic resin is inverted and inserted into the existing pipe in a softened state, the lining material that is not inverted and inserted will extend due to the reversal propulsion force (tension) and the weight of the lining material. The tube thickness becomes uneven. Further, if the lining is applied to a protrusion such as a solid deposit or a weld at the bottom of an existing pipe, or a deviation or a loss of a joint, the lining is extremely thin, and in some cases, the lining is broken.

Also, as shown in JP-A-63-285395, when a pipe softened on the inner surface of a curved pipe is forcibly extended and crimped with a pig from a small diameter, the outer pipe becomes thinner than other parts. There were disadvantages.

Furthermore, as disclosed in European Patent EPO184366A1, the method of inserting a pipe into an existing pipe while making it is impossible to insert the pipe into an existing pipe with significant meandering, etc., or the diameter of the pipe must be reduced. There is a disadvantage that the cross-sectional area decreases greatly with respect to the pipe diameter.

The present invention has been made in order to solve such disadvantages, and proposes a reversing lining method capable of securely adhering a synthetic resin pipe having a uniform pipe thickness to an existing pipe inner surface without using an adhesive or the like. The purpose is to do so.

[Means for Solving the Problems] A reversal lining method according to the present invention comprises a resin pipe formed of a thermoplastic resin and having a shape changed so as to have a small cross-sectional area, and a guide tube made of a heat-resistant film tube connected to a tip end. And a covering tube made of a heat-resistant film tube that covers these components. The tip of the lining material is inverted and fixed in an annular shape to form an inversion portion, and the lining material is inverted into the existing pipe while continuously supplying a heating pressure fluid at a temperature that maintains the softened state of the resin pipe to the inversion portion. It is characterized in that it is inserted, the inserted lining material is cooled while pressing the inserted lining material against the inner surface of the existing pipe, and then the coated tube is pulled out.

[Action] In the present invention, a resin pipe formed of a thermoplastic resin as a lining material, having a shape changed so as to have a small cross-sectional area, and having a leading end connected to a guide tube made of a heat-resistant film tube, and a heat-resistant film covering the same. A reversing part is formed at room temperature by using a lining material composed of a tube and a covering tube, and reversing the tip of the lining material and fixing it in an annular shape.

By inverting and inserting the lining material into the existing pipe while continuously supplying a heating pressure fluid at a temperature that maintains the softened state of the resin pipe to the inversion section, the softened resin pipe is integrally inverted with the coated tube having high tensile strength. .

The inverted and inserted resin pipe is cooled while being pressed by the coating tube to form a synthetic resin pipe having a uniform thickness on the inner surface of the existing pipe. Thereafter, the coated tube is pulled out.

[Embodiment] FIGS. 1 and 2 are process diagrams showing a reverse lining method according to an embodiment of the present invention. In the figure, 1 is an existing pipe,
2 is a lining material.

The lining material 2 is made of a thermoplastic resin and has a shape changed so as to reduce the cross-sectional area;
Guide tube 4 and resin pipe 3
And a covering tube 5 that covers the guide tube 4. As shown in FIG. 3 (a), this lining material 2 is made of a thermoplastic synthetic resin such as vinyl chloride, polyethylene, polypropylene, polybutene or the like at a ratio of 90 to 100% with respect to the inner diameter of the existing pipe 1. Extrusion molding to an outer diameter, and a cylindrical resin pipe 3a having a length equal to or longer than the existing pipeline length
To form Next, the resin pipe 3a is softened in a heating atmosphere having a softening temperature, for example, a heating temperature of 80 to 140 ° C. in the case of vinyl chloride, and the cross-sectional area is already established by a mechanical method such as a molding roller or an extrusion slit. FIG. 3 (b)
A flat or bent resin pipe 3 as shown in (c) and (d) is formed. After forming the resin pipe 3 having a reduced cross-sectional area, the heat deformation temperature under load is higher than the softening temperature of the thermoplastic resin at the tip while maintaining the softened state. For example, the heat deformation temperature under load is 160 ° C. (4.6 kgf / cm ^2). ) Is connected to a guide tube 4 formed of a film of nylon or 135 ° C. (4.6 kgf / cm ² ) polyester or a film containing reinforcing fibers. Thereafter, the resin pipe 3 and the guide tube 4 are covered with a covering tube 5 formed of the same film as the guide tube 4, and the lining material 2 as shown in FIG. 4 is formed.

The guide tube 4 has a length of 1 to 5 m according to the burying depth of the existing pipe 1, and the covering tube 5 has a length equal to or longer than the existing pipe length.

At the rear end of the lining material 2 thus formed,
After connecting the tow rope 23 longer than the total length of the
As shown in Fig. 5, work is made into a circular roll or a folded shape with 23 inside, and then cooled and stored.

Reference numeral 6 denotes a heating and heat-retaining tank. The heating and heat-retaining tank 6 has a heating fluid supply port 7 for supplying a heating fluid such as hot air or steam, a ventilator 8 for discharging the heating fluid, and a lining material outlet 9.

Reference numeral 10 denotes a reversing pressure vessel. The reversing pressure vessel 10 includes an arc-shaped groove 11 provided at a connection portion with the heating and heating tank 6 and a lining material insertion portion 15 including a guide roller 12, a seal plate 13, and a tension roller 14, A fluid supply port 18 provided through a lining material outlet 16 provided in a cylindrical shape at the tip and a valve 17
Having.

Next, an operation when the synthetic resin pipe is lined on the inner surface of the existing pipe 1 by the apparatus configured as described above will be described.

First, as shown in FIG. 1, the guide tube 4 and the coating tube 5 at the end of the lining material 2 are drawn out from the lining material outlet 9 with respect to the guide roller 12 of the heating and keeping tank 6, as shown in FIG. The lined material 2 is stored in the heating and keeping tank 6. The heating and holding tank 6 is installed in a construction place close to the existing pipe 1, for example, near the manhole 19 when the existing pipe 1 is a sewer pipe.

Next, the lining material insertion portion 15 of the reversing pressure vessel 10 is fixed to the lining material outlet 9 of the heating and heat retaining tank 6.

Then, while passing the ends of the guide tube 4 and the coating tube 5 which have been drawn out in advance through the sealing plate 13 and the tension roller 14 of the reversing pressure vessel 10, the lining material insertion portion 15 of the reversing pressure vessel 10 is taken out of the heating and heat retaining tank 6. Fix to outlet 9. Then, the distal ends of the guide tube 4 and the coating tube 5 are pulled out from the inversion pressure vessel 10, and the guide tube 4 is inverted so that the guide tube 4 is on the outside, and is fixed in an annular manner to the lining material outlet 16 with a steel band or the like. An inversion section 20 is formed. When forming the reversing part 20, the tip of the lining material 2 is composed of the guide tube 4 made of a flexible heat-resistant film hose and the covering tube 5, so that the reversing part 20 is easily formed in a normal temperature atmosphere. be able to.

In this state, the guide hose 21 is placed over the lining material outlet 16 and fixed to the lining material outlet 16 as shown in FIG. 1, and the tip 21a of the guide hose 21 approaches the inlet of the existing pipe 1 And install it.

Thereafter, a heating pressurized fluid having a temperature for softening the resin pipe 3 is supplied from the heating fluid supply port 7 of the heating and heat retaining tank 6 to maintain the resin pipe 3 in a flexible state. Then, a propulsion heating fluid 22 having a temperature for keeping the resin pipe 3 in a softened state is continuously supplied from the fluid supply port 18 of the inversion pressure vessel 10. The supply of the propulsion heating fluid 22 causes the reversing portion 20 of the lining material 2 to advance in the guide hose 21, pull out the resin pipe 3 connected to the rear end of the guide tube 4 from the heating and holding tank 6, and insert the resin pipe 3 into the guide hose 21. Reverse and insert. The length of the guide tube 4 is adjusted in advance so that the connection point between the inverted guide tube 4 and the resin pipe 3 is within the guide hose 21.

As the propulsion heating fluid 22 is supplied to the reversing pressure vessel 10, the reversing part 20 of the lining material 2 is connected to the existing pipe 1 as shown in FIG.
The reversing part 20 is inserted into the existing pipe 1 by the pressure difference between the inside and outside.
Proceed inside. When the reversing part 20 advances in the existing pipe 1, the lining material 1 before inversion is pushed from both sides by the pressure of the propulsion heating fluid 22, and therefore proceeds without expansion and expansion. In addition, the resin pipe 3 of the reversing part 20 receives the pressure of the propulsion heating fluid 22 via the coating tube 5 having tensile strength and is reversed integrally with the coating tube 5, so that the thickness variation due to the elongation at the time of the reversal is reduced. Can be prevented. Furthermore, since the resin pipe 3 after the reversal expansion has a slightly smaller diameter of 90 to 100% of the diameter of the existing pipe 1, it can be lined on the inner surface of the existing pipe 1 with a small extension distance.

When the reversing part 20 of the lining material 2 advances to the middle of the existing pipe 1, the traction rope attached to the rear end of the lining material 2
23 is pulled out to the inversion pressure vessel 10, and thereafter the inversion portion 20 is supported by the tension of the traction rope 23. And the reversing unit 20
After proceeding to the end of the existing pipe 1, natural cooling or forced cooling by supplying a cooling fluid is performed while maintaining the pressure inside the lining material 2 at a level that can prevent the lining material 2 from hanging down by its own weight. Then, the temperature of the lining material 2 is reduced to 40 ° C. or less, and the resin pipe 3 is cured to form a synthetic resin pipe.

Thereafter, both ends of the synthetic resin tube are cut. As a result of this cutting, the coated tube 5 having no adhesive property to the resin pipe 3 sags at the bottom of the resin pipe 3 as shown in FIG.
By pulling out the covering tube 5, a self-standing synthetic resin tube over the entire length of the existing tube 1 is completed.

In the above embodiment, the case where the guide tube 4 is connected to the tip of the resin pipe 3 has been described.
The guide tube 4 may be connected to the entire distal end of the resin pipe 3 and the covering tube 5 covering the resin pipe 3.

When the guide tube 4 is not connected, the distal end portions of the resin pipe 3 and the coating tube 5 are heated and softened, and are fixed to the liner outlet 16 of the reversing pressure vessel 10 in a ring shape. It may be formed.

[Effects of the Invention] As described above, the present invention draws a guide tube and a coating tube joined to the tip of a resin pipe from a heating and heat retaining tank, and inverts and fixes them to a lining material outlet of an inversion pressure vessel. Since the lining material can be easily connected to the reversing pressure vessel in a normal temperature atmosphere to form the reversing portion, the lining material can be easily connected to the reversing pressure vessel, and the danger of high temperature during construction can be reduced. It can be prevented and the construction can be performed easily.

Also, after the lining material is connected to the inversion pressure vessel, the lining material is inverted and inserted into the existing pipe while continuously supplying a propulsion heating fluid having a temperature that maintains the softened state of the resin pipe to the inversion portion, thereby softening the resin. Since the pipe can be inverted integrally with the coated tube having tensile strength, deformation of the resin pipe by the propulsion heating fluid can be prevented,
Variations in the thickness of the resin pipe can be prevented.

In addition, since the resin pipe is reverse-lined in a softened state, even if there is a gap in the existing pipe such as a gap, a gap or a crack in the joint, the gap closes or closes the gap, so that the pipe has a substantially uniform thickness. The synthetic resin pipe can be formed in the existing pipe, so that the strength of the synthetic resin pipe can be made uniform and the flow characteristics can be stabilized.

In addition, since the resin pipe is inverted and inserted in a softened state, the time required for inversion and insertion is short, the amount of heat stored in the surrounding soil is small, and after the inversion and insertion, the synthetic resin can be cooled simply by pressing the resin pipe with a coating tube. Since the pipe is formed on the inner surface of the existing pipe, the time for curing the adhesive or the like is not required, and the construction time can be reduced.

In addition, since the existing pipe and the resin pipe are in close contact with each other, the reduction in cross-sectional area is small, and no crout is required, so that the construction can be performed reliably.

[Brief description of the drawings]

1 and 2 are process diagrams showing a reversing lining method according to an embodiment of the present invention, FIG. 3 is an explanatory view showing a processing step of the lining material of the above embodiment, and FIG. 4 is a perspective view showing the lining material. FIG. 5 is a perspective view showing a state in which the lining material is formed into a circular winding, FIG. 6 is a sectional view showing a state in which the lining material is lined in an existing pipe, and FIGS. 7 (a), (b) and (c). And (d) are explanatory diagrams each showing a state at the time of construction. 1 ... existing pipe, 2 ... lining material, 3 ... resin pipe, 4
…… Guide tube, 5… Coated tube, 6… Heat insulation tank, 10… Inverted pressure vessel, 16… Liner material outlet.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location B29L 23:00

Claims (1)

(57) [Claims] 1. A resin tube formed of a thermoplastic resin and having a shape changed so as to have a small cross-sectional area, a guide tube made of a heat-resistant film tube connected to a tip end thereof, and a coated tube made of a heat-resistant film tube covering these. A reverse lining method for forming a synthetic resin pipe on the inner surface of an existing pipe by using a lining material made of a resin pipe, wherein the tip portion of the lining material is inverted and fixed in an annular shape to form a reversing portion, and a resin pipe is formed on the reversing portion. It is characterized in that the lining material is inverted and inserted into the existing pipe while continuously supplying a heating pressure fluid at a temperature that maintains the softened state, and the coated tubing is pulled out after cooling while pressing the inserted lining material against the inner surface of the existing pipe. Reverse lining method.