JPS5937213B2 - Pipe lining method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pipe lining method.

For the purpose of regenerating or repairing aging water pipes or city gas pipes, a lining tube is inserted into the pipe using pressurized air, and the inner surface of the tube is coated in advance before it is turned over. Various methods have been proposed for bonding and lining with adhesive.

In this type of lining construction method, the length of pipe that can be treated in one installation is usually about 100 to 150 m, and it takes a considerable amount of time to install, so it is difficult to use adhesives to bond the tube to the inner surface of the pipe. In general, those that require reaction curing at room temperature for several to ten-odd hours are used. Therefore, even if the tube is reversely inserted into the pipe and lined, the adhesive will not harden immediately, so to prevent the tube from sagging, it is necessary to maintain a certain pressure inside the pipe until the adhesive hardens. arise. However, maintaining the pressure inside the pipe for a long time is not desirable from the viewpoint of construction efficiency and construction management, and attempts have been made to heat the inside of the pipe with a heated fluid such as steam to accelerate the curing of the adhesive. There is. Application of such heating means is effective in accelerating the curing of the adhesive, but when switching from air pressure to steam heating and pressure inside the pipe, there is a risk that the pressure inside the pipe will drop and the lining tube will sag. be. In order to solve this problem, we fixed both ends of the lined tube to the inner surface of the tube using a quick-acting adhesive while maintaining the inner pressure at a specified pressure by applying air pressure. It has been proposed to release the tube and switch to heating and pressurizing with steam, but such a method is not only extremely complicated to operate, but also makes it difficult to guarantee that the middle part will not sag just by fixing the inner end of the tube. . In particular, in order to obtain a smooth inner lining condition,
In the case of expansion lining using a tube with a diameter 5 to 10% smaller than the diameter of the tube to be lined,
Due to tube contraction, it immediately peels off from the inner surface of the tube. The present invention has been made with the aim of eliminating all of the problems of the conventional art, and one embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 schematically shows the process of attaching the terminal fitting 1 and lining the tube 2 in the construction method of the present invention.

Prior to the lining process of the tube 2, the terminal fitting 1 is attached to a pipe 3 to be lined, such as a water pipe or a city gas pipe.
is attached and fixed to the terminal end of the terminal so as to close the terminal opening.

FIG. 2 shows a specific example of the means for attaching and fixing the terminal fitting 1. is fixed at the end of the The joint fitting 4 has locking protrusions 4a, 4a protruding inward at both front and rear ends, and the locking protrusions 4
a, 4a are circumferential grooves 5a on the outer peripheral surfaces of the fixed ring 5 and the terminal fitting 1;
, 1a. Also, the joint fitting 4 is connected to the pipe 3.
It has an inner circumferential surface 4b having the same diameter as the inner circumferential surface 4b, and this inner circumferential surface 4b is subjected to mold release treatment so as not to adhere to the tube adhesive described in detail below. As shown in FIG. 3, the joint fitting 4
can be opened and closed using the hinge part 4c on one end as a fulcrum,
Further, the flat plate portions 4d, 4d on the other end side can be appropriately restrained in a closed state with bolts (not shown). The terminal fitting needs to have an insertion opening 1c in the lid 1b, and nut-shaped members 1d are welded and fixed to several places on the outer surface of the lid 1b so as to surround this insertion opening 1c. ing. The lining tube 2 is inserted from the starting end side of the tube 3 whose terminal end is closed by the terminal fitting 1 in this way.
Inverted insertion using fluid pressure e.g. pressurized air;
The inner surface of the tube 3 is lined.

Such an inversion lining construction method for the tube 2 itself is known, and the known method can be applied as is. tube 2
An example of the inverted lining construction method will be explained based on FIG. The starting end of the lining tube 2 is hermetically fixed to the starting end of the tube 3 through a flexible guide tube 9 that connects the pressurizing chamber 7 and the starting end of the tube 3 to be lined.

Next, pressurized air is supplied into the pressurizing chamber 7 via an air tank 11 mounted on a second truck 10, a combustor 12, and a conduit 13. The pressurized air supplied into the pressurizing chamber 7 flows into the tube 3 through the guide tube 9, and the tube 2 is inserted into the tube 3 while being inverted. This inversion insertion automatically stops when the inversion part 2a of the tube 2 reaches the inner surface of the lid part 1b of the terminal fitting 1, and the inversion insertion step is completed.
The tube 2 that has been inverted and inserted is adhered to the inner surface of the tube 3 using an adhesive that has been applied to the inner surface of the tube 2 in advance before being inverted. It may also be bonded using an adhesive. Note that the second
The bogie 10 is equipped with a boiler 14 in addition to an air tank 11, and both of them are selectively connected to the pressurizing chamber 7 via the conduit 13 by switching a valve (not shown).
Now you can contact us. Fig. 4 shows the connection status between the pressurizing chamber 7 and the starting end of the pipe 3, and the connection status of the tube 2 to the starting end of the pipe 3.
A preferred example of the connection status is shown.

According to this connection structure, the upper end of the flexible guide tube 9 is connected to the pressurizing chamber 7 via the bend guide tube 15, while the lower end is connected to the flange portion 17a of the base 17 via the bend tube 16.
is connected to the outer end of the As in the case of the terminal fitting 1, this cap 17 is fixed to the starting end of the tube 3 via a two-split joint fitting 18 and a fixed ring 19.
The starting end of the tube 2 is hermetically fitted and fixed to the opening 17b which protrudes forward from the front inner circumference of the flange 17a of the tube 7. In addition, the inner circumferential surface 1 of the above-mentioned two-piece joint fitting 18
8a can be subjected to mold release treatment in the same manner as the metal fitting 4. As shown in Fig. 1, after lining the inner surface of the tube 3 with the tube 2 by applying the known inversion insertion method, the air pressure inside the tube 3 is maintained at a predetermined pressure and replaced with pressurized air. Steam is supplied. This steam supply can be easily carried out by opening the inside of the pressurizing chamber 7 to the boiler 14 side via the conduit 13 by switching a valve (not shown). Simultaneously with the supply of steam into the tube 3, the insertion part 20a of the pressurized fluid extraction device 20 is inserted into the tube 2 through the insertion opening 1c of the lid 1b of the terminal fitting 1. Air and steam are appropriately extracted from the inside of the tube 3 through this insertion part 20a, and the temperature and pressure inside the tube are controlled. This control is continued until the adhesive inside the tube is completely cured. The conditions of pressurization and heating inside the tube are schematically shown in FIG. 6 and 7, details of the pressurized fluid extraction device 20 are shown.

As shown in FIG. 6, the sickle-shaped insertion part 20a of the extraction device 20 is first inserted into the tube 2 through the insertion opening 1c of the lid part 1b of the terminal fitting 1, and then from the insertion part 20a. A fixing member 20d screwed onto the threaded portion 20c of the conduit portion 20b extending rearward is fixed to a nut-shaped member 1d on the outer surface of the lid portion 1b around the insertion opening 1c using a bolt 20e. In this state, as shown in FIG. 6, the sickle-shaped insertion part 1a,
There is a gap of 20 g between the collar 20f loosely fitted to the conduit part 20b, and the outer circumferential surface of the conduit part 20b at the 20 g interval is unsealed by the piercing part 20a and contracted due to its elasticity after being unsealed. The periphery of the opening portion 2b of the tube 2 is inscribed. Next, the conduit portion 20b
d as a guide, and as a result, the gap 20g between the sickle-shaped insertion part 20a and the collar 20f disappears, and the tube in the opening part 2b is held between them, and the seal is opened. The parts are kept airtight. This state is shown in FIG. In the state shown in FIG. 7, the conduit section 2
By opening the valve 20h provided at the rear end of 0b, the air and steam inside the tube are removed from the opening 20a of the insertion part 20a.
From there, it can be extracted to the outside of the tube through a passage in the conduit section 20b that communicates with this. In this case, in order to recover the steam extracted from the inside of the pipe, the steam can be guided into the water of the water tank 20k via the hose 201 and the air blowing pipe 20j, as shown in FIG. When the adhesive is completely cured by the pressure and heat treatment inside the pipe 3, the inside of the pipe 3 is released from the pressure and heat by steam, and the lining construction is completed after cooling, draining, and terminal treatment as usual.

In the lining method of the present invention, the terminal fitting 1 is attached and fixed to the end of the tube 3 to be lined, so when the tube 2 is reversely inserted into the tube 3, the inverted part 2a is connected to the lid of the terminal fitting 1. It automatically stops when it reaches the inner surface of 1b, and its termination can be automatically controlled.

Therefore, when performing reverse insertion of the tube with the terminal opening of the tube 3 open, it is necessary to place an operator on the terminal side of the tube 3 to confirm that the reverse insertion has been completed. This arrangement of workers can be omitted. Furthermore, in the present invention, since the insertion port 1c is formed in the lid portion 1b of the terminal fitting 1, this insertion port 1c acts as an exhaust port for the air inside the tube 3 during the reverse insertion process of the tube 2, so that the tube 2 can be smoothly inserted. After the reverse insertion, the pressurized fluid extraction device 20 inserted into the tube 2 through the insertion port 1c removes the pressurized fluid in the tube 3. This makes it possible to easily replace the air with steam while maintaining the air pressure inside the tube 3 at a predetermined pressure, and after replacing the air, the pressurized and heated state by steam can be easily controlled, which increases the heating inside the tube and promotes adhesive curing. The objective is achieved without the risk of sagging of the lined tube and without the need for complex work steps such as the application of fast-acting adhesives.

In particular, with the present invention, the inside of the tube can be maintained at a predetermined pressure from beginning to end, from the time of lining the tube to the complete hardening of the adhesive.
It is extremely useful when a tube with a diameter about 10% smaller is used and expanded to line a pipe. Furthermore, if the tube is lined and bonded to the inside of the pipe using adhesive applied to the inner surface of the tube before inversion, the tube should be glued to the inner surface of the fittings attached to the starting and terminal ends of the tube in addition to the inner surface of the tube. This may cause difficulties in terminal processing.

Such problems can be solved, for example, by using the two-split joint fittings 4 and 1 which have been subjected to mold release treatment, as shown in Example 1 of the present invention.
8, and after the adhesive is completely cured, first remove the joint fittings 4 and 18, expose this part of the tube to the outside, and cut this exposed tube. can be solved.

[Brief explanation of drawings]

The drawings show one implementation state of the construction method of the present invention, and FIG. 1 is an explanatory diagram schematically showing how the tube is reversed and inserted, FIG. 2 is a longitudinal sectional view showing an example of the means for attaching the terminal fitting, and FIG. is 2
Fig. 4 is a vertical cross-sectional view showing an example of the connection between the starting end of the pipe to be lined and the pressure chamber of the bogie soil, and Fig. 5 shows the heating process for the adhesive inside the pipe. The schematic explanatory drawings, FIGS. 6 and 7, are partial longitudinal sectional views showing an example of the use of the pressurized fluid extraction device. In the figure, 1 is the terminal fitting, 2 is the lining tube, 3 is the tube to be lined, 4 is the split joint fitting, 5 is the fixing rod, 6 is the first trolley, 7 is the pressurizing chamber, 8 1 is a reel, 9 is a flexible guide tube, 10 is a second truck, 11 is an air tank, 12 is a compressor, 13 is a conduit, 14 is a boiler, 15 and 16 are bend guide tubes, 17 is a base, and 18 is a two-piece The joint fitting, 19 is a fixed ring, and 20 is a pressurized fluid extraction device.

Claims (1)

[Claims] 1 (a) Attaching a terminal fitting having an insertion port in the lid to the terminal end of the pipe to close the terminal opening of the pipe to be lined; (b) installing the terminal fitting of the pipe whose terminal opening is closed by the terminal fitting; An operation in which the lining tube is reversely inserted using air pressure from the starting end opening side, and the reversely inserted tube is adhered to the inner surface of the tube using an adhesive that has been applied in advance to the inner surface of the tube before being reversed or to the inner surface of the tube. (c) pressurizing steam into the tube while maintaining the air pressure in the tube at a predetermined pressure; (d) At the same time as steam is press-fitted, insert the insertion part of the pressurized fluid extraction device into the tube from the insertion opening of the lid of the terminal fitting, and then extract air and steam as appropriate to reduce the pressure inside the tube. A pipe lining method comprising the step of accelerating the curing of the adhesive while controlling the temperature.