JPH0692119B2 - Lining method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a lining method applicable to sewers, waterworks, oil transmission pipes and any other existing pipes, and more particularly to improvement of adhesion of synthetic resin pipes to existing pipes. .

[Prior art] In recent years, for the purpose of reinforcing the strength of existing pipes such as sewers and waterworks, anticorrosion measures, water leakage and water infiltration measures, and improving the flow rate, synthetic resin is lined on the inner surface of the existing pipe or synthetic resin is applied on the inner surface of the existing pipe The inversion lining method for forming ridges is in the spotlight.

For example, in the method disclosed in Japanese Examined Patent Publication (Kokoku) No. 55-43890 and Japanese Laid-Open Patent Publication No. 64-85738, a needle felt layer is lined with an inner lining material impregnated with a liquid thermosetting resin such as epoxy or polyester under fluid pressure in an existing pipe. To reverse and advance, and press the reversed lining material to the inside 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.

Further, the construction methods disclosed in JP-A-64-16633, JP-A-64-16634 and JP-A-63-285395 are
This is a method in which a small-diameter thermoplastic plastic pipe is inserted into an existing pipe, and then the thermoplastic plastic pipe is heated and pressurized from the inside to be expanded and brought into close contact with the inner surface of the existing pipe.

[Problems to be Solved by the Invention] The lining material used in the conventional reversal method represented by JP-B-55-43890 is a liquid thermosetting resin impregnated in the needle felt layer, which is a reversal surface when reversing in an existing pipe. It moves in the felt layer by a non-uniform pressing force in the circular direction. Therefore, a difference occurs in the resin impregnation amount in the cross-sectional direction of the felt layer,
In addition to variations in thickness, there is a disadvantage that variations in strength occur.

Further, particularly when a long lining material is used, it is necessary to wind or stack it after the impregnation process in order to store the soft lining material impregnated with the liquid resin. At this time, the thickness of each part of the lining material varies due to the difference in its own weight or the pressing force, and the environmental pressure difference is applied to the liquid resin. When a synthetic resin pipe is formed from the lining material in such a state, variations in thickness and strength also 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, and it is difficult to form a uniform synthetic resin tube.

If the existing pipe has gaps such as displacement, loss, and cracks in the joint portion of the technique pipe, the liquid resin around these gaps oozes into the gap due to the pressing force of the existing pipe after reversing, and In addition to the decrease in strength, the liquid resin also flows out together with the underground infiltration water due to the decrease in clay before gelling due to heating, resulting in a porous impregnated layer and a significant decrease in strength.

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

Further, when the thermosetting resin is heat-cured, shrinkage occurs in the longitudinal direction and the circumferential direction of the lining layer. Due to this contraction, a gap is created between the existing pipe and the lining layer, which has a disadvantage of causing intrusion water or water leakage.

Further, as in the method disclosed 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. In order to heat, soften, and expand the pipe, there is a large difference in elongation under the same pressure due to the difference in resin temperature, and when heated, it becomes an amorphous state and there is no self-expansion force, so it is necessary to forcibly expand and expand with external pressure. For this reason, it is necessary to uniformly heat the existing pipe and the resin pipe in the circumferential direction and the longitudinal direction under the same pressure. However, in reality, there are disadvantages that the heating temperature varies, wrinkles are generated in the resin pipe, the pipe thickness varies, and a gap is generated between the heating pipe and the existing pipe.

Further, as disclosed in JP-A-63-285395, when a pipe softened on the outer surface of a curved pipe is forcibly stretched and crimped with a pig from a small diameter, there is no shrinkage in the softened state, so the outer surface is covered with other parts. Compared with the thinner pipe, there was a disadvantage that the stretched portion inside had wrinkles on the downstream side in the traveling direction.

The present invention has been made to solve such disadvantages, and an object thereof is to propose a lining method capable of reliably adhering a synthetic resin pipe to the inner surface of an existing pipe without using an adhesive or the like. Is.

[Means for Solving the Problems] A lining method according to the present invention is a heat-resistant film for covering a resin pipe and a resin pipe, which are formed of a shape memory resin and have a changed shape so as to have a small cross-sectional area, as an lining material for an existing pipe. It is a construction method that uses a lining material consisting of a tube, and pulls the lining material while maintaining the ambient temperature in the existing pipe above the shape recovery temperature of the resin pipe and below the shape memory temperature, and lining from one end of the existing pipe. The invention is characterized in that the expansion jig is pressure-fed into the material and the film tube is pulled out in synchronization with the pressure-feeding of the expansion jig.

[Operation] In the present invention, as the lining material, an lining material having a resin pipe formed of a shape memory resin and having a changed shape so as to have a small cross-sectional area is used. By drawing into the existing pipe whose temperature is above the recovery temperature and below the shape memory temperature,
Since the film tube is pulled in while suppressing the shape recovery of the softened resin pipe, the lining material can easily pass through the bent portion.

By pulling out the film tube while feeding the expansion jig into the softened lining material, the shape of the resin pipe is restored while sending out the air and accumulated water existing between the existing pipe and the lining material.

[Embodiment] FIGS. 1A and 1B are process diagrams showing a 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 composed of a resin pipe 3 which is made of a shape memory resin and whose shape is changed so as to have a small cross-sectional area, and a heat-resistant film tube 4 which covers the resin pipe 3. This lining material 2
As shown in the process diagram of Fig. 2, a shape memory made of, for example, block copolymer of polystyrene and crystallized polybutadiene (made by Asahi Kasei Kogyo), trans polyisoprene (made by Kuraray) or polyurethane resin (made by Mitsubishi Heavy Industries). The resin is extruded into a pipe shape in a heating atmosphere having a shape memory temperature of, for example, 120 ° C. or more, and a shape having an outer diameter of 100 to 150% of the inner diameter of the existing pipe 1 is memorized to form the resin pipe 3. To do. Next, while the resin pipe 3 is being softened in a heating atmosphere having a shape recovery temperature (rubberization temperature) of 90 ° C. or higher to a shape memory temperature or lower, a cross-sectional area of the existing pipe is formed by a mechanical method such as a molding roller or an extrusion slit. Flattened to be smaller than the cross-sectional area of 1 or bent or bent to make the resin pipe 3 or flattened to have a smaller diameter as shown in FIGS. 2 (b), (c), (d) and (e). The bent resin pipe 3 or the flat resin pipe 3 is formed. After the resin pipe 3 having a small cross-sectional area is formed, the load heat deformation temperature is immediately higher than the shape memory temperature of the shape memory resin while maintaining the softened state, for example, the load heat deformation temperature is 16
Nylon at 0 ° C (4.6Kgf / cm ² ) or 135 ° C (4.6Kgf / c ² )
The lining material 2 as shown in FIG. 2 (f) is formed by covering with a film tube 4 made of a film of polyester or the like of m ² ) or a film in which reinforcing fibers are put.

5 is a sealing part attached to one end of the existing pipe 1,
The sealing part 5 has a supply port 6 for heating water sent from a heating boiler (not shown) and a pressurizing water supply port 7 to which a seal part is attached and which supplies pressurized water. Reference numeral 8 denotes a sealing portion attached to the other end of the existing pipe 1. The sealing portion 8 has a heating water discharge port 9 to which a safety valve 91 is attached and a seal portion to which the lining material 2 is inserted, and The film tube 4 has a drawing port 10 for drawing the film tube 4. 11 is an extension jig, and the extension jig 11
Is made of, for example, a pig made of polyethylene. Reference numeral 12 is a speed control rope attached to the rear end of the extension jig 10.

Next, the operation of the embodiment in which the synthetic resin pipe is formed on the inner surface of the existing pipe 1 by using the lining material 2 formed as described above will be described.

First, the sealing portion 5 having the extension jigs 11 built in at both ends of the existing pipe 1.
And the sealing portion 8 are attached to make the existing pipe 1 almost sealed. Next, while continuously supplying heated water from the sealing unit 5 and discharging the supplied heated water from the heated water discharge port 9 of the sealing unit 8,
Resin pipe 3 that forms the lining material 2 at the temperature inside the existing pipe 1
Keep the temperature above the shape recovery temperature and below the shape memory temperature.

In this state, as shown in FIG. 1 (a), the extraction port of the sealing portion 8
Insert the lining material 2 into the existing pipe 1 from 10. As the lining material 2 is inserted into the existing pipe 1, the resin pipe 3 of the lining material 2 is softened by the temperature inside the existing pipe 1, and the existing pipe 1
The lining material 2 is arranged along the shape of. At this time, the softened resin pipe 3 expands, but the film tube 4
The resin pipe 3 is in a state in which it is not recovered to its original shape because it is covered with and the expansion action is restricted.

After arranging the lining material 2 in the existing pipe 1, the supply of the heating water sent from the supply port 6 of the sealing portion 5 is stopped, and the pressurized water is supplied from the pressurized water supply port 7, as shown in FIG. As shown in b), the expansion jig 11 is pressure fed into the lining material 2. At this time, when the film tube 4 is pulled out in conjunction with the speed control rope 12 so that the rear end portion 4a of the film tube 4 is always located at the front end portion of the expansion jig 11, the resin pipe 3 in a softened state While expanding the pressing portion 3a pressed by the expansion jig 11 to the outside by the shape recovery force of the resin pipe 3 and the pressing force of the expansion jig 11, the air and the accumulated water existing between the existing pipe 1 and the resin pipe 3 While recovering the shape of the resin pipe 3.

Since the original outer diameter of the resin pipe 3 is formed to be 100 to 150% of the inner diameter of the existing pipe 1, the recovery force for recovering the outer diameter and the pressing force of the expansion jig 11 are mutually dependent. By the action, the resin pipe 3 is completely adhered to the inner surface of the existing pipe 1 without an adhesive.

At this time, the heated water in front of the pressing portion 3a is the expansion jig.
According to the pressure of 11, the water is discharged from the heated water discharge port 9.

In this way, after the resin pipe 3 is brought into close contact with the entire inner surface of the existing pipe 1, cooling water is supplied instead of pressurized water to cool the resin pipe 3 and form a synthetic resin pipe in the existing pipe 1.
After that, the sealing parts 5 and 8 and the extension jig 11 are removed, and post-processing such as cutting both ends of the formed synthetic resin pipe is performed to complete the processing.

In addition, although the above-mentioned embodiment explained the case where the existing pipe 1 is a straight pipe, even if the existing pipe 1 has the bent portion 14 as shown in FIG. 3, it can be applied similarly to the above-mentioned embodiment. it can.

Even with such a bent portion 14, when the lining material 2 is drawn into the existing pipe 1, the resin pipe 3 of the lining material 2 is softened by the temperature in the existing pipe 1 and the lining material 2 becomes flexible. Therefore, according to the shape of the bent portion 14, the lining material 2 can be arranged without resistance.

Further, by pressing the lining material 2 with the expansion jig 11, it is possible to prevent the generation of the air pocket 15 and the wrinkles 16 of the resin pipe 3 which occur in the bent portion 14 as shown in FIG.

Further, in the above-described embodiment, the heating water is supplied into the existing pipe 1 so that the temperature is maintained above the shape recovery temperature of the resin pipe 3 forming the lining material 2 and below the shape memory temperature. A heating hose or a heating element having a plurality of holes through which the heating fluid is passed, or a heating element such as a nichrome wire is embedded in the film tube 4 of the lining material 2 to keep a predetermined temperature by electric heating. A heating hose having embedded therein may be provided in the resin pipe 3 to maintain a predetermined temperature.

When a heating hose is provided in the resin pipe 3,
The heating hose may be pulled out at the same time as the film tube 4.

[Effects of the Invention] As described above, the present invention uses, as the lining material, a lining material having a resin pipe formed of a shape memory resin and having a changed shape so as to have a small cross-sectional area, and a film tube covering the resin pipe. However, by drawing this lining material into the existing pipe whose ambient temperature is above the shape recovery temperature of the resin pipe and below the shape memory temperature, the lining material is made flexible and the shape of the softened resin pipe Since the recovery is suppressed by the film tube and the film is drawn into the existing pipe, the lining material can be easily arranged according to the shape of the existing pipe even if the existing pipe has a bent portion.

Also, by pulling out the film tube while feeding the expansion jig into the softened lining material, the shape of the resin pipe can be restored to its original shape while sending out the air and accumulated water existing between the existing pipe and the lining material. Since the synthetic resin pipe is formed so as to recover the shape, the synthetic resin pipe can be completely adhered to the existing pipe without using an adhesive or the like, and the occurrence of water infiltration and water leakage can be prevented.

In addition, since the plastic pipe is molded to an accurate pipe thickness and then flattened and stored and transported in the solid state, variations in thickness and strength during storage are eliminated, and the formed synthetic resin pipe has a uniform pipe thickness and uniform thickness. It becomes stronger and can be remarkably improved in quality.

In addition, since a synthetic resin pipe can be formed in an existing pipe without using an adhesive or the like, no curing time for the adhesive or the like is required, so there is no heat storage in the soil, the cooling time is extremely short, and the existing pipe is simple. Since the base treatment is sufficient, the construction time can be greatly reduced.

Furthermore, since no attachment device such as an adhesive is required, the connecting portion with the existing pipe can be small, and the construction can be performed even from the manhole of the sewer pipe, and the construction cost can be reduced.

[Brief description of drawings]

FIG. 1 is a process drawing showing a construction process of an embodiment of the present invention, FIG. 2 is a process drawing showing a working process of a lining material used in the above embodiment, and FIGS. 3 and 4 are other embodiments. FIG. 1 ... Existing pipe, 2 ... lining material, 3 ... resin pipe, 4
…… Film tube, 5,8 …… Sealing part, 6 …… Supply port, 7 …… Pressurized water supply port, 9 …… Heating water discharge port, 10 ……
Draw-out port, 11 …… extension jig, 12 …… speed control rope.

Claims (1)

[Claims] 1. A synthetic resin pipe is formed on the inner surface of an existing pipe by using an inner lining material made of a shape memory resin and having a shape changed so as to have a small cross-sectional area, and a heat-resistant film tube covering the resin pipe. A lining method for pulling the lining material while maintaining the ambient temperature in the existing pipe at a temperature not lower than the shape recovery temperature of the resin pipe and not higher than the shape memory temperature, and an extension jig is inserted from one end of the existing pipe into the lining material. The lining method is characterized in that the film tube is pulled out in synchronism with the feeding of the expansion jig.