JPH0155839B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is mainly concerned with repairing the pipe joints of existing gas pipes that are buried underground so as to ensure sealing performance from the inside of the pipe while the pipes are still buried. The present invention relates to an introduction device for introducing repair resin and a resin transporting pig into an existing pipe when repairing a pipe joint of an existing pipe.

[Conventional technology]

In existing pipes such as gas pipes that are connected underground (under roads) by connecting long cast iron pipes with water-type pipe joints, the joints of the pipe joints are susceptible to the load of vehicles passing over the pipes, earthquakes, etc. Alternatively, the joint condition may change over time, creating gaps in the joint, or the constituent materials of the joint may deteriorate, causing leaks. , it has been considered to repair the pipe fittings of existing pipes from the inside of the pipe while they are still buried.

As a type of repair equipment, a resin transporting pig is introduced into the existing underground pipe, and the pig is pulled by a towing cable and moved along the inner surface of the pipe. A pipe joint repair device has been proposed in which the gaps between a plurality of pipe joints interposed in an existing pipe are sequentially filled with a resin placed in the pipe joint.

[Problem to be solved by the invention]

However, with the above-mentioned conventional repair equipment, when repairing a pipe joint, it is not only troublesome to introduce the resin and the resin transporting pig into the pipe of the existing pipe, but also when filling the resin, the space in front of the pig is It is necessary to discharge the air accumulated in the pipe outside the pipe to prevent air from getting mixed into the resin, and the initial preparation work for repairing these pipe joints is troublesome and requires a lot of time and effort.

The present invention solves the above-mentioned problems and enables the initial preparation work for pipe joint repair to be carried out intensively and efficiently, and the introduction of resin and a pig for carrying the resin into the pipe when repairing the pipe joint of an existing pipe. The aim is to provide equipment.

[Means to solve the problem]

In order to achieve the above object, the present invention introduces a resin transporting pig into an existing underground pipe, and moves the pig by pulling it with a tow cable and moving it along the inner surface of the pipe. In the process of filling the gaps between multiple pipe joints in the existing pipe with resin placed on the front side of the pig, the existing pipe is divided into repair units of a predetermined length, and the separated existing pipes are repaired. One open end is exposed in a pit opening above the ground, and a pig insertion conduit with the pipe end bent toward the ground is removably connected to the separation opening with a clamp, and the conduit includes: A resin filling port and an air discharge port are provided that communicate with the resin filling tank, and a pig is connected to a tow cable that passes a tow cable from the pipe end of the pipe into the existing pipe, and the pig connects to the pipe end entrance of the pipe. When the resin is introduced into the pipe, the resin is introduced into the space in front of the pig from the resin filling port, and when the resin is introduced, the air remaining in the space in front of the pig is discharged from the air discharge port to the outside of the pipe. It is characterized by:

[Effect]

A pig insertion conduit whose pipe end bends toward the ground is connected to one open end of an existing pipe that opens in a pit that opens above the ground and is divided into predetermined lengths. A pig connected to the tow cable passed through the existing pipe is introduced into the entrance.
At this time, the resin from the resin filling tank is introduced into the space in front of the pig through the resin filling port communicating with the tank, while the air remaining in the space is discharged from the air outlet to the outside of the pipe. This prevents air from getting mixed into the resin, making it possible to perform initial preparatory work for pipe joint repair in an intensive and efficient manner.

〔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 equipment, and in Fig. 1, reference numeral 1 indicates an existing pipe to be repaired that is installed underground. A long cast iron pipe of the same size is connected by a water pipe joint 13. In repairing the pipe joint 13 of the existing pipe 1, in the present invention, 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 of the repair section L is The other separated end 12 is exposed in the shaft A opened above the ground and into the shaft B also opened above the ground, and a pig insertion conduit 5, which will be described later, is connected to the separated ends 11 and 12.
Connect the pig lead-out conduit 6.

Then, the tow rope 4 is passed through the existing pipe 1 from one of the pig insertion conduits 5 and pulled out from the other pig lead-out conduit 6, and the tip of the tow rope 4 is wound up with a winch 9. , a pair of front and rear pigs 2 and 3 are attached to the tow rope 4, and a low-viscosity resin C is placed in front of the front pig 2, and a joint sealing resin D is placed in front of the rear pig 3, respectively. It is configured to be introduced into the existing pipe 1 while being pulled and moved inside the pipe from the inlet side to the outlet side.

As shown in an enlarged view in FIG. 4, the pig 2 has a structure in which sealing fins are protruded at intervals around the periphery of a cylindrical body, and collars 28 and 29 with clamps are provided at the front and rear. The center of the cylinder has a hole through which the tow cable 4 is inserted, so that air can flow back and forth, and the collars 28 and 29 are fixed to the tow cable 4 by clamping them to the tow cable 4.

In addition, since the rear pig 3 needs to be equipped with a resin replacement function as shown in FIG. Replacement grooves 18 are formed on the outer circumferential wall of the pig 3, and replacement grooves 18 are formed on the upper and lower outer circumferential walls of the pig 3 so as to be parallel to the grooves 18 on the body of the pig 3. And these grooves 17, 18
The rear end walls in the traveling direction are formed into tapered end walls 17a and 18a that are obliquely inclined toward the rear, and the replacement groove 18 is formed on the rear side pig 3.
It communicates with a passage 19, such as a polyethylene tube, buried within the pig so as to open at the rear end of the pig.

As described above, the pigs 2 and 3 having such a configuration are inserted into the existing pipe 1 in the repair section L, and move the low-viscosity resin C and the joint sealing resin D along the inside of the pipe, and in this movement process, This is to repair a plurality of pipe joints 13 interposed within the section, and the pipe joints 1
3, as shown in FIG. 6, for example, the large-diameter portion 13a provided at the end of one tube is fitted with the other end 13b, and the fitting portion is usually provided with a "hemp skin". It has a structure in which a sealing material 14 called .

As described above, the existing pipe 1 to be repaired has the pig insertion conduit 5 connected to one separated end 11 and the pig lead-out conduit 6 connected to the other separated end 12, but these conduits 5 , 6 are Fig. 2, Fig. 3
Shown enlarged in the figure.

As shown in FIG.
It is removably connected to the base, and the tip is bent toward the ground. This pig insertion conduit 5 includes:
A resin filling opening 5a is provided, and an opening/closing pot 52 is provided there. Further, an exhaust port 5b is provided at a slightly higher level position, and an opening/closing pot 53 is provided there.
The resin filling port 5a is communicated with 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 by driving a generator 7b.

Further, as shown in FIG. 3, the pig lead-out conduit 6 is provided with a discharge port 6a for discharging the residual resin, and an opening/closing pot 61 is provided at the discharge port 6a. Further, above the discharge port 62,
The conduit 6 includes an air supply pipe 6 for adding air pressure to the existing pipe 1 on the front side in the direction of movement of the pigs 2 and 3.
b is provided, and this air supply port pipe 6b is connected to the compressor 10 via the pressure operation unit 10a.
is communicated with. Also, the tow cable 4 passing through the conduit 6
A lid 8 equipped with a guide reel 81 for leading out the tow line 6 is removably attached to the open end of the conduit 6 by a clamp 82, and this lid is split in half at the lead-out part of the tow rope 4. ing.

The tip of the tow rope 4 is wound around the drum 9a of the winch 9, and by winding the tow rope 4, the pigs 2 and 3 are inserted into the existing pipe 1 through the insertion conduit 5. and upon this insertion,
First, the front side pig 2 is inserted, and the resin C is supplied from the tank 7 to the front side of the pig 2 through the hose 7a and the resin filling opening 5a under the pressure of the compressor 7c. Note that this resin C has the effect of adhering to and removing dust in the existing pipe 1 and dust in the space of the pipe joint part 13 with its own adhesive property.

Next, the rear pig 3 is inserted into the conduit 5, with the space between the front pig 2 and the rear pig 3 corresponding to the resin filling opening 5a as shown in FIG. Pause the movement of 2 and 3 and move to Kotoku 5.
2 is opened and resin D is filled into the space in front of the pig 3 from the tank 7 under the pressure of the compressor 7c. At this time, the opening/closing pot 53 is opened to discharge the air in the space, and the air is led out of the tube from the discharge port 5b. In order to prevent the rear pig 3 from slipping out of the inlet end of the conduit 5 due to the filling pressure during filling with the resin D, a cross pin 54 is detachably attached to the outer end of the conduit 5.

In this way, with the space between the front and rear pigs 2 and 3 sufficiently filled with resin D, the tow rope 4 is attached to the winch 9.
When the resin filling is completed, the pot 52 is closed. Then, the pigs 2 and 3 are pulled by the pulling operation of the tow rope 4 and move inside the existing pipe 1 along its inner surface.

When the rear pig 3 reaches the position of the pipe joint part 13 by pulling the pigs 2 and 3 (see Fig. 6), the resin D on the front side of the rear pig 3 is removed from the inner wall of the existing pipe 1 during the pulling movement. Sufficient filling pressure is generated at the rear end of the resin due to the viscous resistance between the two and the resin D flows into the joining space of the pipe joint part 13 through the groove 17 on the outer periphery of the pig. On the other hand, from the joining space of the pipe joint part 13, the air staying there is naturally pushed out rearward via the other groove 18 by receiving the above-mentioned filling pressure. In addition, at this time,
Negative pressure may be applied to the rear space of the rear pig 3 to suck and discharge air from the pipe joint 13 via the groove 18.

After the rear pig 3 passes, resin enters the branch mouth of the branch pipe 40 (supply pipe) branched from the existing pipe 1;
Pressure air is drawn in from the outside and released into the existing pipe 1. The released resin may be later passed through a copying pig or the like to smoothen the inner wall of the existing pipe 1.

When the repair to the pipe joint part 13 is completed, remove the clamp 82, remove the lid 8 and divide it into two parts, open the pot 61, first draw out the resin C on the front side of the front side pig 2, and then Lead out the rear pig 3. Then, the bolts 28a and 28b are loosened to release the tightening of the collar 28, and the pig 2 and tow line 4 are removed.
When the pig 2 is released and the winch 9 pulls the towing line 4, the front pig 2 does not move and only the rear pig 3 climbs up the inside of the conduit 6. At this time, the residual resin is collected into the container 41, for example, from the discharge port 6a. In this case, since the lid 8 is divided into two parts as shown in the figure, even if the tow line 4 is wound around the winch 9, the pigs 2, 3
It does not get in the way of taking out.

In this embodiment, resin is filled and supplied between the front side pig 2 and the rear side pig 3 and carried into the existing pipe 1, and the resin is filled into the pipe joint space by displacement action in the pipe joint part 13. Therefore, we decided to put the pigs 2 and 3 into the pig introducing conduit 5 in advance and fill the space between them with resin. However, we filled this pipe joint with resin only using the replacement pig without using the front pig. Of course, the pig introduction conduit 5, resin filling port 5a, exhaust port 5b, etc. may also be used in this case.

〔Effect of the invention〕

As described in detail above, the present invention divides an existing pipe into repair units of a predetermined length during repair, and exposes one separation opening of the separated existing pipe in a vertical hole that opens above the ground. A pig insertion conduit whose pipe end is bent toward the ground is removably connected to the separation opening, and the conduit is provided with a resin filling port and an air discharge port communicating with the resin filling tank. Therefore, by inserting the pig through the conduit, it is extremely easy to introduce the pig into the existing pipe, and when inserting the pig from the end of the conduit, the space in front of the pig is removed from the resin filling port. The resin can be filled and supplied to the pipe, and when the resin is filled and supplied, the air remaining in the space in front of the pig can be discharged from the air outlet to the outside of the pipe, so that air is not mixed into the resin. Initial preparation work for pipe joint repair can be accomplished efficiently and efficiently.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the entire repair device showing one embodiment of the present invention, Fig. 2 is a schematic side view showing a portion of a conduit for inserting a pig, and Fig. 3 is a schematic side view showing a portion of a conduit for leading out a pig. , FIG. 4 is a longitudinal sectional side view showing a state in which the pig is being pulled, FIG. 5 is a perspective view of the rear pig, and FIG. 6 is an enlarged sectional view of a main part showing a resin filling state. 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, 41...Container, 5...Pig insertion conduit, 5
a...Resin filling port, 5b...Exhaust port, 51
... Clamp, 52, 53 ... Kotsuku, 54 ...
Cross pin, 8... Pig lead-out conduit, 6a... Discharge port, 6b... Air supply port pipe, 61... Opening/closing pot, 7... Resin filling tank, 7a... Hose, 7b... Generator, 7c...compressa, 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)

[Claims] 1. A resin transporting pig is introduced into an existing underground pipe, and the pig is pulled by a towing cable and moved along the inner surface of the pipe, and in the process of movement, the front side of the pig is In this method, the existing pipes are divided into repair units of a predetermined length,
One open end of the separated existing pipe is exposed in a pit that opens above the ground, and in the separated opening,
Pig insertion conduits bent with their pipe ends facing the ground are removably connected by clamps, and the conduit is provided with a resin filling port and an air discharge port that communicate with the resin filling tank, and the pipe of the conduit is A towing cable is passed into the existing pipe from the end, a pig is connected to the towing cable, and when the pig is introduced into the pipe end entrance of the conduit, resin is introduced into the space in front of the pig from the resin filling port. , a resin and resin transportation during repair of a pipe joint of an existing pipe, characterized in that the air remaining in the space in front of the pig is discharged from the air outlet to the outside of the pipe when the resin is introduced. Pig intraductal introduction device.