JPH03215022A - Reverse lining - Google Patents

Abstract

PURPOSE:To securely adhere a synthetic resin pipe having uniform wall thickness to the inner surface of existing pipe by a method wherein the lining material is reversed and inserted in the existing pipe under the condition that heated pressure fluid, which has the temperature for keeping resin pipe under softening state, is continuously fed to a reversing part so as to press lining material to insert against the inner surface of the existing pipe and to cool the lining material and finally covering tube is drawn out. CONSTITUTION:By reversing and annularly fixing the tip part of lining material 2, a reversing part 20 is formed. By reversing and inserting the lining material 2 in the existing pipe 1 under the condition that heated pressure fluid 22, which has the temperature for keeping resin pipe 3 under softening state, is continuously fed to the reversing part 20, the softened resin pipe 3 is integrally reversed together with covering tube 5 having tensile force. By cooling down the reversed and inserted resin pipe 3 under the condition being pressed by the covering tube 5, synthetic resin pipe having uniform wall thickness is produced on the inner surface of the existing pipe 1. Thus, the synthetic resin pipe having almost uniform wall thickness can surely be formed in the existing pipe.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention is applicable to sewerage systems. Water supply. This invention relates to an inversion lining method that can be applied to oil pipes and all other existing piping, particularly to improving the adhesion of synthetic resin pipes to existing piping.

[Conventional technology] In recent years, strength reinforcement and anti-corrosion measures have been developed for existing pipes such as sewerage and waterworks. For the purpose of water leakage/flooding countermeasures or flow improvement, etc.
Inversion lining methods that line the inner surface of existing pipes with synthetic resin or form synthetic resin on the inner surface of existing pipes are attracting attention.

For example, Japanese Patent Publication No. 55-43890, Japanese Patent Publication No. 64-
The method disclosed in Japanese Patent No. 85738 is to apply epoxy to a layer of 21 dollar felt. Lining material impregnated with liquid thermosetting resin such as polyester is inverted inside existing pipes using fluid pressure. In this method, the inner surface of the existing pipe is lined with a synthetic resin by advancing and pressing the inverted lining material against the inner surface of the existing pipe using fluid pressure, curing the thermosetting resin.

Also, JP-A-64-16633. JP-A-64-1
The method disclosed in Publication No. 6634 or Japanese Unexamined Patent Publication No. 63-285395 involves inserting a small-diameter thermoplastic pipe into an existing pipe, and then heating and pressurizing the thermoplastic pipe from the inside to expand it. This is a method of bringing it into close contact with the surface.

Furthermore, the construction method disclosed in European patent EPOI84366AI involves inserting a spirally wound thin synthetic resin plate into an existing pipe while making it into a spiral shape using a winder (pipe making Pa), and then inserting the lining material into the existing pipe. The space is filled with grout material.

[Problems to be Solved by the Invention] In the lining material used in the conventional inversion method as typified by Japanese Patent Publication No. 55-43890, the liquid thermosetting resin impregnated into the 21-Dolphelt layer is inverted within the existing pipe. Sometimes it moves within the felt layer due to non-uniform pressing force acting in the circumferential direction of the inverted surface.

For this reason, there is a difference in the amount of resin impregnated in the cross-sectional direction of the felt layer, which has the disadvantage of causing not only variation in thickness but also variation in strength.

In addition, especially when using a long lining material, it is necessary to roll up or fold the flexible lining material impregnated with liquid resin after the impregnation process in order to store it. At this time, variations in thickness occur in each part of the lining material due to differences in dead weight or pressing force, and a difference in environmental pressure is applied to the liquid resin. When a synthetic resin pipe is formed using lining material in this condition, there will still be variations in thickness. Variations in strength occur.

Further, it is very difficult to uniformly impregnate the liquid resin over the entire length of the flexible bag, and a variation of ±15% usually occurs, making it impossible to form a uniform synthetic resin pipe.

In addition, if there are gaps such as misalignment, loss, or cracks in the pipework or joints of existing pipes, the liquid resin around these gaps will seep into the gaps due to the pressing force of the existing pipes after reversing. In addition to a decrease in strength, there was also the disadvantage that the viscosity of the liquid resin decreased before gelation due to heating, causing it to flow out together with underground water, forming a porous impregnated layer and significantly decreasing strength.

In addition, the lining material impregnated with thermosetting resin is heated and cured after being turned over and molded, but the total time of heating time and cooling time during heat curing is, for example, 300+nm in diameter and 6n+n thick in the lining material. It takes about 15 hours when polyester resin is used. Also, even the quick-drying type of epoxy resin takes about 6 to 8 hours, which is a disadvantage in that it takes a long time to dry. This is also due to the fact that heat is accumulated in the existing pipes and the surrounding soil during the long heating retention period, which slows down the cooling rate.

Also, JP-A-64-16633. JP-A-64-1
In order to heat, soften, and expand a thermoplastic resin pipe that has been processed into a smaller cross-sectional shape than the existing pipe diameter, as in the construction method disclosed in Publication No. 6634 or Japanese Unexamined Patent Publication No. 63-285395, it is necessary to It has a large difference in elongation rate under pressure, becomes amorphous when heated, and has little self-expansion force, so it must be forcibly elongated and expanded using external pressure. For this reason, it is necessary to uniformly heat both the circumferential and longitudinal directions of the existing pipe and the resin pipe under the same pressure. but,
In reality, the disadvantages are that the heating temperature varies, wrinkles occur in the resin tube, variations in tube thickness occur, and gaps are created between the tube and the existing tube.

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 expand due to the inversion driving force (tension) and the lining material's own weight, so the resin pipe after lining will The pipe thickness may become uneven. In addition, if the lining is applied to the accumulated solids at the bottom of the existing pipe, protrusions such as welds, or misaligned joints, the lining will become thinner in those areas and may even tear. .

Furthermore, as shown in Japanese Patent Application Laid-Open No. 63-285395,
When a small-diameter pipe is forcibly stretched and crimped with a big pipe that has softened on the outside of the inner surface of a curved pipe, the outside pipe thickness becomes thinner than the other parts, which is a drawback.

Furthermore, as disclosed in European Patent EPO184366A1, the method of inserting into an existing pipe while manufacturing the pipe is
This method has the disadvantage that it cannot be inserted into existing pipes that have significant meandering, or the diameter of the pipe must be made smaller, resulting in a large reduction in cross-sectional area relative to the diameter of the existing pipe.

This invention was made to solve these shortcomings, and proposes an inversion lining method that can reliably attach a synthetic resin pipe of uniform thickness to the inner surface of an existing pipe without using adhesives or the like. The purpose is to [Means for Solving the Problems] The inversion lining construction method according to the present invention uses a resin pipe made of thermoplastic resin whose shape is changed to reduce the cross-sectional area and a guide tube made of a heat-resistant film tube is connected to the tip. , and a covering tube made of a heat-resistant film tube that covers these constitutes a lining material. The tip of this lining material is inverted and fixed in a ring shape to form an inverted part,
The lining material is reversed and inserted into the existing pipe while continuously supplying heated pressure fluid at a temperature that maintains the softened state of the resin pipe to this reversal section.The inserted lining material is cooled while being pressed against the inner surface of the existing pipe, and then the covered tube It is characterized by pulling out. [Function] In this invention, a resin pipe is formed of a thermoplastic resin as a lining material, the shape is changed so that the cross-sectional area becomes small, and a guide tube made of a heat-resistant film tube is connected to the tip, and a heat-resistant film that covers these pipes. An inverted section is formed at room temperature by using a lining material made of a tube and a covering tube, and by inverting the tip of this lining material and fixing it in an annular shape.

By inverting and inserting the lining material into the existing pipe while continuously supplying heated pressure fluid at a temperature that maintains the softened state of the resin pipe to this inversion part, the softened resin pipe is inverted together with the tensile strength covering tube. .

This inverted and inserted resin pipe is cooled while being pressed with a covering tube to form a synthetic resin pipe of uniform thickness on the inner surface of the existing pipe. Then, pull out the covering tube.

[Example] Figure 1. FIG. 2 is a process diagram showing an inverted lining construction method according to an embodiment of the present invention. In the figure, l is the existing pipe, 2
is the lining material. The lining material 2 includes a resin pipe 3 made of thermoplastic resin whose shape has been changed to reduce the cross-sectional area, a guide tube 4 connected to the tip of the resin pipe 3, and a coating that covers the resin pipe 3 and guide tube 4. It consists of a tube 5.

This lining material 2 is made of vinyl chloride, for example, as shown in (a) of the explanatory diagram of FIG. polyethylene. Voribropyrene. A cylindrical resin pipe 3a having a length longer than the length of the existing pipe line is formed by extruding thermoplastic synthetic resin such as bolybdenum so that the outer diameter is 90 to 10% of the inner diameter of the existing pipe l.
form. Next, the resin pipe 3a is heated to a softening temperature.
For example, vinyl chloride is softened in a heated atmosphere with a thermal processing temperature of 80 to 140°C, and processed using mechanical methods such as forming rollers and extrusion slits so that its cross-sectional area becomes smaller than that of the existing pipe. Figure 3(b)
．． (C) Form a flat or flattened resin pipe 3 as shown in (d). After forming the resin pipe 3 with a reduced cross-sectional area, the tip is heated while maintaining its softened state so that the heat deformation temperature under load is higher than the softening temperature of the thermoplastic resin, for example, the heat deformation temperature under load is 160°C (4.6
Kgf/cm2) nylon or 135°C (4
．． A guide tube 4 made of a polyester film (6 kgf/cm") or a film containing reinforcing fibers is connected to the guide tube 4. Then, a covering tube 5 made of the same film as the guide tube 4 is used to connect the resin pipe. 3
and guide tube 4 to form a lining material 2 as shown in FIG.

This guide tube 4 has a length depending on the buried depth of the existing pipe 1.
The length of the covering tube 5 is 5 m or more, and the length of the covering tube 5 is longer than the length of the existing pipe line.

After connecting the traction row 123 longer than the entire length of the lining material 2 to the rear end of the lining material 2 formed in this way, the traction row 123 is connected to the rear end of the lining material 2 formed in this way.
With 23 inside, it is processed into a circular roll or folded shape as shown in FIG. 5, and then cooled and stored.

6 is a heating and heat-insulating tank, and the heating and heat-insulating tank 6 is heated with hot air. It has a heating fluid supply port 7 for supplying heating fluid such as steam, a venturator 8 for discharging the heating fluid, and a lining material outlet 9. 1O is an inverted pressure vessel, and the inverted pressure vessel 1O has an arcuate groove 11 provided at the connection point with the heating and insulation tank 6, and a guide roller 12. Temporary seal 13 and tension roller l4
It has a lining material insertion portion l5 consisting of a lining material insertion portion l5, a lining material bow outlet l6 provided in a cylindrical shape at the tip, and a fluid supply port l8 provided via a valve l7.

Next, the operation of lining the inner surface of the existing pipe 1 with a synthetic resin pipe using the apparatus configured as described above will be explained.

First, the guide tube 4 and the covering tube 5 at the tip of the lining material 2 are passed through the guide roller l2 of the heating/insulating tank 6 and pulled out from the lining material outlet 9, and then wound up as shown in FIG. The heated lining material 2 is stored in a heating and heat-retaining tank 6. This heating and heat-insulating tank 6 is installed at a construction site 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 l5 of the inverted pressure vessel 10 is fixed to the lining material outlet 9 of the heating and heat-insulating tank 6.

Thereafter, the tips of the guide tube 4 and covering tube 5, which have been pulled out in advance, are inverted and attached to the seal plate 13 of the pressure vessel 10. The lining material insertion part 15 of the inverted pressure vessel IO is fixed to the lining material outlet 9 of the heating and heat-insulating tank 6 while passing through the tension roller 14. Then, the guide tube 4 and the covering tube 5
The tip of the tube is pulled out from the inverted pressure vessel lO, inverted so that the guide tube 4 is on the outside, and fixed in an annular manner to the lining material outlet l6 with a steel band or the like to form an inverted portion 20 of the lining material 2. When forming this inverted part 20, since the tip of the lining material 2 is composed of a guide tube 4 made of a flexible heat-resistant film hose and a covering tube 5, the inverted part 20 can be easily formed in an atmosphere at room temperature. be able to.

In this state, as shown in Fig. 1, the guide hose 2l is placed over the lining material outlet l6 and fixed to the lining material outlet l6, and the tip 21a of the guide hose 2l is brought close to the inlet of the existing pipe l. and install it.

Thereafter, heated pressurized fluid at a temperature that softens 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, the propulsion heating fluid 22 having a temperature that maintains the resin pipe 3 in a softened state is continuously supplied from the fluid supply port 18 of the inverted pressure vessel IO. By supplying this propelling heating fluid 22, the inverted portion 2 of the lining material 2
0 advances through the guide hose 2l, the resin pipe 3 connected to the rear end of the guide tube 4 is pulled out from the heating and heat-insulating tank 6, and is reversed and inserted into the guide hose 2l. 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 2l. Heating fluid 2 propelled into the inverted pressure vessel lO
2, the inverted portion 20 of the lining material 2 becomes the second
As shown in the figure, the reversing part 20 is inserted into the existing pipe 1, and moves inside the existing pipe 1 due to the pressure difference between the inside and outside. This reversal section 2
When 0 moves through the existing pipe 1, the lining material 1 before inversion is pressed from both sides by the pressure of the propelling heating fluid 22, so it expands. Proceed without expansion. Furthermore, since the resin pipe 3 of the reversing section 20 receives the pressure of the propulsion heating fluid 22 via the tensile covering tube 5 and is reversed integrally with the covering tube 5, variations in thickness due to elongation during reversing are avoided. This can be prevented from occurring. Furthermore, the resin pipe 3 after inversion and expansion has a diameter of 90 to 100% of the diameter of the existing pipe l.
Since the diameter is slightly small (0%), it is possible to line the inner surface of existing pipes with a small extension distance. When the inverted part 20 of the lining material 2 advances to the middle of the existing pipe l, the traction lobe 23 attached to the rear end of the lining material 2 is pulled out to the inverted pressure vessel 10, and thereafter the inverted part 20
is supported by the tension of the traction row 123. and,
After the reversing section 20 has advanced to the terminal end of the existing pipe 1, it is forced to cool naturally or by supplying cooling fluid while maintaining pressure inside the lining material 2 to the extent that it can prevent the lining material 2 from sagging due to its own weight. Cool to bring the temperature of the lining material 2 below 406C and harden the resin pipe 3 to form a synthetic resin pipe. Then, cut both ends of the synthetic resin pipe. Due to this cutting, the covering tube 5 does not have adhesiveness to the resin pipe 3.
sag at the bottom of the resin pipe 3 as shown in Figure 6. By pulling out this covering tube 5, a self-supporting synthetic resin pipe is completed over the entire length of the existing pipe 1.

In the above embodiment, the case where the guide tube 4 is connected to the distal end of the resin pipe 3 has been described, but the guide tube 4 may be connected to the entire distal end of the resin pipe 3 and the covering tube 5 that covers the resin pipe 3. You may do so.

Also, when the guide tube 4 is not connected,
The inverted portion 20 may be formed by heating and softening the tips of the resin pipe 3 and the covering tube 5 and fixing them in an annular manner to the lining material outlet l6 of the inverted pressure vessel 10.

[Effects of the Invention] As explained above, the present invention has the following advantages: by pulling out the guide tube and the covering tube joined to the tip of the resin pipe from the heating and insulating tank, and inverting and fixing them to the lining material outlet of the inverted pressure vessel. Since the lining material can be easily connected to the inverted pressure vessel in a normal temperature atmosphere to form an inverted section, the lining material can be easily connected to the inverted pressure vessel, reducing the risk of high temperatures during construction. It can be prevented and the construction can be done easily. In addition, after connecting the lining material to the inverted pressure vessel, the lining material is inverted and inserted into the existing pipe while continuously supplying the propulsion heating fluid at a temperature that maintains the softened state of the resin pipe to the inverted section. Since the pipe can be inverted together with the tensile covering tube, it is possible to prevent the resin pipe from being deformed by the propellant heating fluid, and it is possible to prevent variations in the thickness of the resin pipe. In addition, since the resin pipe is reverse lined in a softened state, there is no possibility of misalignment of the joint part with the existing pipe. Even if there is a gap such as a loss or crack, the resin pipe will adhere and close the gap, so a synthetic resin pipe of almost uniform thickness can be formed inside the existing pipe, and the strength of the synthetic resin pipe will be uniform. At the same time, flow characteristics etc. can also be stabilized.

Furthermore, since the resin pipe is reversed and inserted in a softened state, the time required for reversal and insertion is short, and the amount of heat stored in the surrounding soil is small.
Moreover, after being reversed and inserted, the synthetic resin pipe is formed on the inner surface of the existing pipe by simply cooling it while pressing the resin pipe with the coating tube, so there is no need for hardening time for adhesives, etc., and the construction time can be shortened. can.

Furthermore, 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 clout is required, so construction can be carried out reliably.

[Brief explanation of drawings]

Figure 1. Fig. 2 is a process diagram showing the inverted lining method according to the embodiment of the present invention, Fig. 3 is an explanatory diagram showing the processing process of the lining material of the above embodiment, Fig. 4 is a perspective view showing the lining material, and Fig. 5 6 is a perspective view showing a state in which the lining material is rolled in a circular shape, FIG. 6 is a sectional view showing a state in which the lining material is lined inside an existing pipe, and FIG. 7(a). (b). (c). (d) is an explanatory diagram showing the state at the time of construction. l...Existing pipe, 2...Lining material, 3...Resin pipe, 4...Guide tube, 5...Coating tube, 6...Heating and insulation tank, lO ...Inverted pressure vessel, l6... Lining material outlet.

Claims (1)

[Scope of Claims] A resin pipe made of thermoplastic resin, whose shape is changed so that the cross-sectional area is small, and a guide tube made of a heat-resistant film tube is connected to the tip thereof, and a covering tube made of a heat-resistant film tube that covers these pipes. This is an inverted lining method in which a synthetic resin pipe is formed on the inner surface of an existing pipe using a lining material made of The lining material is inverted and inserted into the existing pipe while continuously supplying heated and pressurized fluid at a temperature that maintains the softened state of the pipe, and the inserted lining material is pressed against the inner surface of the existing pipe, cooled, and then the covering tube is pulled out. This is an inverted lining construction method.