JPH0155840B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a method for repairing existing pipes that are installed underground, by using a resin introduced into the existing pipe for repair and a pig for transporting the resin. This relates to a device that guides the pipe out of the pipe after the repair is completed.

[Conventional technology]

Recently, existing pipes such as gas pipes that are piped underground, especially cast iron pipes that are connected for a long time using water-type pipe fittings and piped underground (under roads), have been exposed to the joints of the pipe joints. The joint condition of the pipe may change due to the load of vehicles passing over the pipe, earthquakes, or over time, creating gaps in the joint, or the material (sealing material) of the joint may deteriorate, causing leaks. For the purpose of leakage repair or preventive maintenance, it has been considered to repair the pipe fittings of existing pipes from the inside of the pipe while leaving them buried.

As a type of repair equipment, a pig, which is pulled by a towing cable and slides in airtight contact with the inner surface of the pipe, is introduced into the pipe of an existing underground pipe, with resin placed on the front side of the pig. , a pipe joint repair device has been proposed that sequentially fills the gaps between multiple pipe joints in an existing pipe with resin during the process of moving the resin along the inside of the pipe by pulling a pig. .

[The problem that the idea attempts to solve]

However, according to the above-mentioned repair device, when the repair of a predetermined section is completed, the residual resin introduced into the pipe must be discharged from the pipe end and received in a container, and then the pig must be guided out from the pipe end. Moreover, if the pressure air supply section is provided at the end of the tube, there is a problem that the above-mentioned work becomes even more troublesome.

The present invention has been made to solve the above problems.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a pig that is pulled by a towing cable and slides in airtight contact with the inner surface of the pipe inside an existing underground pipe, and a resin is placed on the front side of the pig. In a repair device that fills the gaps between multiple pipe joints in an existing pipe with resin, the existing pipe to be repaired is , during repair, divide the existing pipe into repair units of a predetermined length, expose one exit-side separation opening of the separated existing pipe in a shaft that opens above ground, and direct the separation opening toward the ground within the shaft. A bent pig lead-out pipe is connected to the lead-out pipe in a detachable manner, and the lead-out pipe is provided with a residual resin discharge port and a pressurized air supply port, and a lid body having a tow cable outlet is attached to the lead-out pipe. It is characterized by being removably fitted into the outlet of the tube end.

[Effect]

With the above configuration, the repair of the pipe joint intervening in the existing pipe divided into repair units is completed, and the pig is connected to the outlet side opening of the existing pipe that opens in the shaft that opens above the ground. When reaching the pig lead-out pipe that is bent toward When the pipe is removed and the repair is completed, the completion work can be carried out continuously and easily, and the preparation work for the repair of the next repair section can be carried out. Air pressure is applied from the air supply port to the resin on the front side of the pig to promote its flow into the joining space of the pipe joint, thereby improving workability.

〔Example〕

Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a diagram schematically showing the entire repair construction apparatus, and reference numeral 1 in the figure indicates an existing pipe to be repaired that is installed underground. This is a long underground piping system in which cast iron pipes of a predetermined size are sequentially connected using water pipe joints 13 using a conventional piping method.

As shown in an enlarged view in FIG. 7, the pipe joint part 13 of the existing pipe 1 has, for example, a large diameter part 13a provided at the pipe end of one pipe, and a pipe end 13b of the other pipe. The butt-fitting part is filled with a sealing material 14, usually called "hemp skin," and the opening is sealed with a lead material 15. ) In the existing pipe 1 installed in the pipe 1, for the reasons mentioned above, the connection state of the pipe joint 13 may change and create a gap, or the sealing material 14 may deteriorate and cause leakage. The need for repair arises, and in this case, in the present invention, the gap between the pipe joint portion 13 and the sealing material 14 are fixed.
The aim is to repair the seal by infiltrating and filling it with resin to improve its sealing effect.

In the present invention, when repairing the pipe joint part 13 of the existing pipe 1, the existing pipe 1 is first divided into repair sections L each having a length suitable for repair (for example, 100 m), and one separated end 11 is exposed to a pit A opened above the ground, and the other separated end 12 is exposed to a pit B also opened above the ground.

A pig insertion conduit 5 in the shape of a curved tube with its tip bent toward the ground is removably connected to one of the separation ends 11 as an inlet side at the separation opening with a clamp. As shown in an enlarged view in FIG. 2, the pig insertion conduit 5 is provided with a resin filling opening 5a and an air exhaust opening 5b located at a slightly higher level. , these openings 5a and 5b each have an opening/closing knob 52,
53 are provided. The resin filling opening 5a
is connected to the resin filling tank 7 via a hose 7a, and the filling pressure to the resin filling tank 7 is applied from a small compressor 7c driven by a generator 7b.

In the present invention, the other separation end 12 is used as the outlet side, and in the present invention, the extraction pipe 6 of the pig is connected to the separation opening.

The lead-out pipe 6 of this pig is bent so that the pipe end faces the ground, and the lead-out pipe 6 has a third
As shown in the enlarged figure, a resin discharge port 6a for discharging residual resin is located in a portion facing diagonally upward.
is provided, and an opening/closing pot 61 is provided there. Further, at a position above the resin discharge port 61, the lead-out pipe 6 is provided with pigs 2 and 3.
An air supply port pipe 6b for supplying pressurized air is provided in the existing pipe 1 on the front side in the direction of movement of the pressure operating unit 10a.
The compressor 10 is connected to the compressor 10 via the compressor 10. Further, the lead-out pipe 6 has a lid 8 equipped with a guide reel 81 for leading out the tow rope 4 pulled out from inside the existing pipe 1.
is removably attached to the open end of the outlet pipe 6 by a clamp 82.

The lid 8 includes a half lid 8a in which a guide reel 81 is supported by a bracket 83 as shown in FIG.
The outlet 84 for the tow cable 4 is configured in combination with the remaining half-cover 8b, and the outlet 84 for the tow cable 4 is formed by combining the remaining half-covers 8a, 8.
It is provided at the matching point b. The lid 8 has a groove 8c on its outer periphery, and is inserted into a coupler 85 provided at the open end of the outlet pipe 6. By operating a clamp lever 86, the coupler 85 is inserted.
A cam 87 provided therein fits into the groove 8c and is prevented from coming off.

Therefore, during repair work, the towing cable 4 is passed from one of the pig insertion pipes 5 into the existing pipe 1 and pulled out from the other pig lead-out pipe 6, and the tip of the towing cable 4 is connected to the drum 9a of the winch 9. By winding it up, the pair of front and rear pigs 2 and 3 attached to the tow rope 4 are coated with a low viscosity resin C on the front side of the front side pig 2, and a joint sealing material on the front side of the rear side pig 3. Resin D is introduced into the existing pipe 1 from the resin filling tank 7 under the pressure of the compressor 7c through the hose 7a and the resin filling opening 5a, and the resin D is introduced into the existing pipe 1 from the inlet side to the outlet side. towing,
will be moved.

The front pig 2 has a structure in which sealing fins are protruded from the periphery of a cylindrical body at intervals, as shown in an enlarged view in FIG. Furthermore, the center of the cylinder has a hole through which the tow rope 4 is inserted, allowing air to flow back and forth, and by clamping the collars 28 and 29 to the tow rope 4, the front pig 2 is fixed to the tow rope 4. has been done.

In addition, since the rear pig 3 needs to have a resin replacement function as shown in FIG. Replacement grooves 18 are formed on the body of the pig 3 so as to be parallel to the replacement grooves 18 on the upper and lower outer circumferential walls of the pig. And these grooves 17,1
8, each rear end wall in the traveling direction is formed into tapered end walls 17a, 18a that are obliquely inclined toward the rear, and the replacement groove 18 is formed of, for example, a polyethylene tube buried in the pig. The passage 19 is opened to the rear of the rear pig 3 through a passage 19 .

Therefore, when the pigs 2 and 3 are towed by the winding of the tow rope 4 by the winch 9, and the resins C and D are moved inside the existing pipe 1 by being pulled by the pigs 2 and 3, the resin C in the previous stage is 1 and the space of the pipe joint part 13, which adheres to the resin and removes it due to its adhesive properties.

Furthermore, when the rear pig 3 reaches the position of the pipe joint 13 (see Fig. 7), the resin D on the front side of the rear pig 3 has a viscosity between it and the inner wall of the existing pipe 1 during the towing movement. Resin pressure is generated in the resin itself due to resistance, and air pressure from the pressurized air supply port 6b acts on the existing pipe 1 on the front side in the direction in which the resin travels, and this air pressure is applied to the resin D through the center hole of the front pig 2. These filling pressures cause the resin D to form the grooves 17 on the outer circumference of the pig.
It flows into the joining space of the pipe joint part 13 through.
On the other hand, from the joint space of the pipe joint part 13, the air remaining there is naturally pushed out rearward via the other groove 18 by receiving the filling pressure. In this way, the resin D penetrates into the sealing material 14 from the abutment gap of the pipe joint part 13 and is filled, and the pipe joint part 13 is filled with the resin D.
This sealing effect is achieved.

The repair of the many pipe joints 13 interposed in the existing pipe 1 in the repair section is completed by the movement of the resins C and D by the above-mentioned pulling by the pigs 2 and 3, and the front pig 2 pulls the pig from the end of the existing pipe 1. When reaching the inside of the lead-out pipe 6, the winding of the winch 9 is temporarily stopped. Then, the clamp 82 is removed and the lid 8 is removed, and the pot 61 is opened to remove the remaining resin C in front of the front pig 2 from the resin discharge port 6a.

Next, the collar with clamp 28 of the front side pig 2,
29 is released from the clamp, the front pig 2 is uncoupled from the tow rope 4, the front pig 2 is freed from the tow rope 4, and the winch 9 is used to pull the tow rope 4. Pig 2 does not move,
Only the rear pig 3 climbs up inside the outlet pipe 6.
At this time, the residual amount of resin D remaining in front of the rear pig 3 is discharged from the resin discharge opening 6a and placed in the container 41.
The front pig 2 is pushed by the movement of the rear pig 3 and taken out from the tube end outlet of the front and rear pig 2, 3 lead-out tubes 6. In this case, since the lid 8 is divided into two parts as shown, the tow rope 4
Even if the winch 9 is wrapped around the front and rear pigs 2,
It does not get in the way of taking out item 3.

In carrying out the present invention, in the illustrated embodiment, it is necessary to temporarily stop the operation of the winch when the front pig 2 is drawn into the outlet pipe 6, and so that the winch operator can recognize this. pig 2
Attach a marker piece, such as a piece of iron, to an appropriate position on the tow rope 4 further forward, so that the front pig 2 is connected to the lead-out pipe 6.
It would be a good idea to make it possible to confirm from the outside that you have reached this position.

In addition, when the pigs 2 and 3 are introduced into the lead-out pipe 6, a sensor detects this, turns on the switch, and issues a warning. It may be possible to notify that the pig 3 has entered the outlet pipe 6.

〔Effect of the invention〕

Thus, according to the present invention, when the repair of the existing pipe in the repair section is completed, the residual resin can be discharged and collected by winding the winch and the pig can be taken out in a labor-saving and efficient manner. The work becomes simple and easy, and it is possible to immediately move on to repairing the next repair section, making it possible to significantly improve the efficiency of the repair work.

Further, the pig lead-out pipe is removably provided with a lid having a tow cable outlet at the pipe end outlet, so that the pipe end outlet can be closed, and the pig lead-out pipe is provided with a cover body having a tow cable outlet at the pipe end outlet. Since it is equipped with a supply port to supply pressurized air into the existing pipe, the outlet pipe can handle the pressure required to flow resin into the joint space when repairing the joint of the existing pipe. It has an air supply function, and as a result, the structure of the repair work apparatus itself can be simplified, and the workability can be improved, among other effects.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the entire repair equipment showing an embodiment of the present invention, Fig. 2 is a schematic side view showing the pig insertion conduit portion, and Fig. 3 is a schematic side view showing the pig lead-out pipe portion. , FIG. 4 is a longitudinal side view showing the pig in a towed state, FIG. 5 is a perspective view of the rear pig, FIG. 6 is a perspective view of the lid that closes the outlet of the pipe end of the pig lead-out pipe, and FIG.
The figure is an enlarged cross-sectional view of the main parts showing the state of resin filling. 1... Existing pipe, 11, 12... Separation end, 13...
... Pipe joint part, 13a ... Large diameter part, 13b ... Pipe end, 14 ... Seal material, 15 ... Lead material, 17,1
8...Groove, 17a, 18a...Tapered end wall, 1
9...Passage, 2...Front side pig, 28, 29...Collar, 3...Rear side pig, 4...Tow rope, 40...
Branch pipe, 41... Container, 5... Pig insertion conduit, 5
a...Resin filling port, 5b...Air discharge port,
51... Clamp, 52, 53... Kotsuku, 54
...Cross pin, 6...Pig outlet pipe, 6a...Discharge port, 6b...Air supply pipe, 61...Opening/closing pot, 7...Resin filling tank, 7a...Hose,
7b... Generator, 7c..., Compressor, 8...
... Lid, 81 ... Guide rail, 82 ... Clamp, 9 ... Winch, 9a ... Drum, 10 ...
Compressor, 10a...pressure operation unit,
A, B... pit, C, D... resin.

Claims (1)

[Scope of Claims] 1. A pig that is pulled by a towing cable and slides in airtight contact with the inner surface of the pipe is introduced into an existing underground pipe with a resin placed on the front side of the pig, and the pig is In the process of moving the resin along the inside of the pipe by pulling the resin, the repair equipment fills the gaps between multiple pipe joints in the existing pipe with the resin. The separated existing pipe is divided into repair units, and one exit side separation opening of the separated existing pipe is exposed in a shaft opening to the ground, and a pig bent toward the ground is inserted into the separation opening in the shaft. The pipes are removably connected, the lead-out pipe is provided with a residual resin discharge port and a pressurized air supply port, and a lid body having a tow cable outlet is attached to and detached from the pipe end outlet of the lead-out pipe. A device for introducing repair resin and a pig during repair work of an existing pipe, characterized in that it can be fitted freely.