JPS6118462A - Device for repairing pipe joint of existing pipe - Google Patents

Abstract

PURPOSE:To perform secure repair without consuming resin uselessly by applying a flexible covering body for enlarging a part of a dragging wire to large diameter to the external periphery of the dragging wire in a specified range in the front side of a pig. CONSTITUTION:Pigs 2, 3 inserted into an existing pipe 1 through an inserting pipe are drawn by the operation of the dragging wire 4. In this stage, resin C having low viscosity charged to the front side of the front pig 2 diffuses to the inside of the pipe 1 and into dusts incorporated in the space of a pipe joint 13 to improve the lubricity of the internal periphery of the pipe 1 and makes movement of resin D to be filled in the joint and the movement of a hind pig 3 easier. Furthermore, since a cylindrical body 14 is provided to the external periphery of the dragging wire 4 at the front side of the pig 3 in the stage for drawing the pigs 2, 3, the length in the inside of the pipe 1 occupied by the resin D is increased and the viscous resistance is increased and the resin pressure is also increased. Moreover, the time for filling the resin to the joint part is prolonged. Therefore, the filling time to the joint part is prolonged and the repair is performed securely with less consumption of resin.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a pipe joint repair device for existing pipes, which repairs the pipe joints of existing pipes, such as gas pipes, which are mainly installed underground, from the inner surface of the pipe while the pipe is buried to ensure sealing performance. be.

[Conventional technology]

Connect cast iron pipes to long lengths (connect them underground) using pipe fittings such as water pipes.
For existing gas pipes installed under the road,
The condition of the joints may change due to the load of vehicles passing over the pipes, earthquakes, or changes in the ground over time, resulting in gaps in the joints or deterioration of the materials that make up the joints. Recently, due to the cause of gas leakage,
For the purpose of leakage repair or preventive maintenance, it has been considered to repair the pipe joint part of the existing pipe from the inside of the pipe while it is buried. One of these repair methods is to divide the existing underground pipe into repair units of a predetermined length, and then slide the pipe from one separated opening into the existing pipe in the repair section in airtight contact with the inner surface of the pipe. A moving pig is inserted with resin placed on the front side of the pig, and as the pig is pulled by a tow cable and moved inside the pipe toward the other separation opening, the resin is transferred to the existing pipe. A repair method for pipe joints has been proposed in which the gaps between a plurality of intervening pipe joints are sequentially filled6.

[Technical problem of the invention]

When using this repair method, the amount of resin placed on the front side of the VIG must be greater than the required amount in order to ensure that the resin is filled into the gap at the pipe joint by pulling the VIG. There is. That is, in order to reliably fill the joint with resin, the resin pressure ('0.3~0
．． 5kg/cm2) and requires a longer filling time than a predetermined amount. The resin pressure is stopped by the viscous resistance between the resin and the tube wall by pulling the VIG, but if necessary, it may be supplemented by applying air pressure from the front of the resin. The time required to fill the joint with resin is determined by the supply length of the resin injected into the pipe, assuming that the VIG and the resin are towed at a constant speed. The amount of resin for a given length is also required for the joint at the final end of the pipe to be repaired, so it is necessary to fill the many joints with resin in addition to the amount of resin supplied to the specified length. A corresponding amount of resin is required. This resin is supplied from one separation opening of the existing pipe divided into repair units of a predetermined length, that is, the starting end of the side where the VIG is inserted, and the surplus is supplied from the other separation opening. However, it is desirable that the amount of resin discharged at the other opening is as small as possible since it is difficult to reuse this resin and it is usually discarded. However, as mentioned above, in order to reliably fill the pipe fittings close to the other separation opening with resin by moving the VIG, it is necessary to supply a larger amount of resin than the actual amount to fill each pipe fitting. I got it.

[Purpose of the invention]

In view of the above-mentioned circumstances, the present invention aims to reduce the amount of resin supplied to the front side of the pipe, thereby eliminating wasted resin and making it possible to more reliably fill the pipe joint with resin. The present invention aims to provide a pipe joint repair device.

[Structure of the invention]

In order to achieve this object, the present invention provides an outer pouch body made of a flexible material that covers the outer periphery of the tow rope and makes it have a large diameter, on the outer circumference of the tow rope in front of the above-mentioned big frame over a predetermined length range. It is characterized by the fact that

【Example】

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings. Figure 1 is a diagram schematically showing the entire repair construction equipment, and reference numeral 1 indicates an existing pipe to be repaired that is installed underground. (approximately 3 m in length) are connected by a pipe joint 13 such as a water supply type pipe. In order to repair the pipe joint part 13 of the existing pipe 1, in the present invention, the existing pipe 1 is first divided into unit repair sections each having a length suitable for the repair, for example, 100n+. There will be about 30 to 40 of them), and one of the separated ends 11 is placed in a pit A opened above the ground, and the other separated end 12 is
are respectively exposed in a vertical hole B which is also opened above the ground, and a VIG insertion conduit 5 and a VIG lead-out conduit 6, which will be described later, are connected to these separated ends 11 and 12. And 1j for inserting one big
The tow rope 4 from the Ig 5 is passed through the existing pipe 1 and pulled out from the other VIG lead-out conduit 6, and the tip of the tow rope 4 is wound up with the winch 9, thereby removing the pair of front and rear attached to the tow rope 4. Big 2゜3 is introduced into the existing pipe with low viscosity resin C placed in front of the front side Big 2 and resin for filling the joint part placed in front of the rear side Big 3.
It is configured to be towed and moved inside the pipe from the inlet side to the outlet side. The front side big 2 and the rear side big 3 are shown in FIGS. 2 and 4.
As shown in the figure, the front big 2 is made of a soft elastic material (such as a hard neoprene sponge with a hardness of about 50 degrees) and a hard elastic material (such as neoprene rubber with a hardness of about 60 degrees). It has three (3) fin pieces in the drawings, and, although not shown, a passage for pressurized air passing through in the front-rear direction is provided near the center portion fixed to the tow rope 4. Since the rear side big 3 needs to be equipped with a resin storage Mk function, grooves for resin introduction that communicate and open toward the front in the direction of travel are formed on the outer peripheral portion of the rear side big 3 at the left and right outer peripheral wall positions of the big. In addition, H conversion grooves are formed parallel to this at the upper and lower outer circumferential wall positions of the big. In addition, a cylindrical body 14 made of a flexible synthetic resin body is fitted onto the outer periphery of the tow rope 4 in front of the rear big 3 over a predetermined length range. 4 is formed so that the outer periphery thereof is thick. This cylindrical body 14 is connected to the existing pipe 1
The thickness and length may be changed as appropriate depending on the thickness of the joint, the type (viscosity) of the joint sealing resin, etc. In addition, instead of the cylinder 14, as shown in FIGS. 5 and 6, a plurality of jacket pieces 14a made of a flexible material are attached to the tow rope 4 in front of the rear big 3 with a locking member 15. It may be tightened and installed, and by moving the second and third bigs, the outer circumference of the towing cable 4 is covered and the diameter becomes larger. Furthermore, in place of the cylinder 14, a windsock-like jacket piece 14b as shown in FIGS. 7 and 8 is attached to the tow rope 4 in front of the rear big 3 with a wire 1G, and The outer periphery of the tow rope 4 may be covered by movement. As mentioned above, the Vig 2.3 with the above structure is inserted into the existing pipe 1 in the repair section and moved along the low viscosity resin C1 joint filling resin D8 pipe, and during this movement process, the The purpose is to repair a plurality of pipe joints 13 interposed within the pipe.The pipe joints 13 are installed at the pipe end of one pipe, for example, by fitting the large diameter part of the other pipe into the pipe joint part 13. , the butt fitting part is filled with a sealing material usually called "hemp skin", and the frontage part is sealed with a lead material.The above-mentioned VIG insertion conduit 5 is shown in FIG. Existing pipe 1 as shown in
is removably connected to the opening of one separation end 11 of the via a clamp 51, and this VIG insertion guide 5 is provided with a resin injection port 5a, in which an opening/closing cock is provided. 52 are provided. In addition, an exhaust port 5b is provided at a level slightly higher than the opening.

[There is an opening/closing cock 53 installed there. The resin injection tank 5a
is in communication with a resin injection tank 7 via a hose 7a, and the injection pressure to this tank 7 is given from a complete tree 7c by driving a generator 7b. - Furthermore, as shown in FIG. 3, the VIG lead-out conduit 6 is provided with a discharge port 6a for discharging the residual resin, and an opening/closing mechanism 1 is provided at the discharge port 6a. Above the discharge port 6a, the conduit 6 is provided with an air pressure supply pipe 6b, which is communicated with the compressor 10 via a pressure operation unit 10a. In addition, a lid 8 equipped with a guide pulley 81 for guiding the tow rope 4 through the conduit 6 is connected to the conduit 6.
Attaches removably to the open end of the device using a clamp 82.
It is being The lid 8 is configured to be split in half so that it can be attached or detached at the lead-out portion of the tow rope 4 even in the middle of the rope. [Construction Procedures] 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 bigs 2 and 3 are inserted into the existing pipe 1 through the insertion conduit 5. During this insertion, the front side big 2 is inserted first, and the low viscosity resin C is supplied to the front side thereof. Next, the rear side big 3 is inserted into the conduit 5, and the resin for filling the joint part is poured from the tank 7 with the gap between the front side big 2 and the rear side big 3 corresponding to the resin injection opening 5a. It is injected with the pressure of the compressor 7C. At this time, the opening/closing cock 53 is opened to discharge the air in the gap, and the air is led out through the discharge port 5b. A cross bottle 54 is removably attached to the outer end of the conduit 5 in order to prevent the rear VIG 3 from being pulled out of the inlet end of the conduit 5 due to resin injection pressure. With the resin fully injected into the gap between the big 2.3, the cock 52
is closed and the towing/hauling line 4 is pulled by the drive of the winch 9. Vig 2.3 is being pulled by towing rope 4, but
The resin C in front of the big 2 penetrates the dust in the existing pipe 1 and the dust in the space of the pipe joint 13, and improves the lubricity of the inner peripheral surface of the existing pipe 1. movement becomes smoother. In this way, when the bigs 2 and 3 are pulled by the tow rope 4, the cylindrical body 14 or the jacket piece 14a is attached to the outer periphery of the tow rope 4 on the front side of the big 3,
14b is installed, the length of the resin becomes longer inside the existing pipe 1 due to the cylindrical body 14 or the jacket piece 14a, so the viscous resistance of the resin increases, and the resin pressure increases. In addition, since the amount of resin is small, the time required for filling the joint with resin is also long.In addition, when the outer covering piece 14b is provided, when passing through a curved pipe, the outer covering piece 14b Since the pipe does not come into direct contact with the inner surface of the pipe, it will not be damaged. [Operation of the invention] When the rear pipe 3 reaches the position of the pipe joint part 13 due to the traction of the pipe pipes 2 and 3, the pipe will not be damaged. In some resin pipes, the amount of resin in the existing pipe 1 increases due to the cylindrical body 14 or the jacket piece 14a during towing and movement, and the viscous resistance between it and the inner wall of the existing pipe 1 causes enough resin to reach the rear end of the pipe. Since the filling pressure is generated and the air pressure supplied from the compressor 10 is applied to the front of the existing pipe 1 from the supply port pipe 6b,
Due to this filling pressure and front air pressure, the resin is filled into the joint space of the pipe joint portion 13 via the resin introducing groove of the big 3. Moreover, the cylinder body 14. Outer covering piece 14. Since the length of the resin inside the existing pipe increases due to a, the resin is attached to the pipe joint part 13.
The time for filling the bonding space can also be made sufficiently long. On the other hand, from the joining space of the pipe joint part 13, the air remaining in the space and the sealing material is naturally pushed out rearward C through the replacement groove of the big 3 by receiving the filling pressure. In addition, at this time, negative pressure may be applied to the rear space of the rear side big 3, and air may be sucked and discharged from the pipe joint part 13 via the replacement groove. Initially, the resin filling pressure into the pipe joint 13 was more than sufficient because the amount of resin on the front side of the big 3 was large, the contact surface with the inner wall of the existing pipe 1 was large, and the viscous resistance was large. Since the time may be short, it is better to increase the pulling speed at which the Big 3 passes through the pipe joint part 13, but in the process of filling resin into several pipe joints, the front side of the Big 3 The amount of resin ' decreases, and with this decrease, the contact area with the inner surface of the existing pipe 1 decreases, the viscosity resistance decreases, and the filling pressure exerted on the resin decreases. Therefore, in the present invention, the cylindrical body 14 or the outer cover piece 14a is provided on the outer periphery of the tow rope 4 on the front side of the big 3, so compared to the conventional case where this is not provided, even if there are fewer resin gaps, the resin The filling pressure can be increased, and the initial resin supply amount may be reduced. Moreover, the cylinder body 14. Since the jacket piece 14a has flexibility, it can pass through a curved pipe without any trouble, even if it is a curved pipe as shown in FIG. 2, for example. Furthermore, the jacket piece 14a is easier and more convenient to attach to and detach from the tow rope 4 than the cylindrical body 14. In addition, by controlling the towing speed of the tow rope 4 to maintain a predetermined speed in the initial stage and reduce the towing speed in the latter stage when the amount of resin has decreased, the resin filling time can be made almost uniform. be able to. In this embodiment, air pressure is introduced into the front of the existing pipe 1 from the supply port 6b through the pressure operation unit 10a by the action of the compressor 10, passes through the front pig 2, and is applied to the resin resin to reduce viscous resistance. This covers the filling pressure drop due to the drop. In addition to controlling the towing speed and front supply air pressure of the VIG, it is also possible to alleviate restrictions on the towing speed by selecting an appropriate resin viscosity, or to control the differential pressure between the front and rear sides of the VIG3, such as the rear Even if control such as applying negative suction pressure to the side pipe 3 is performed, sufficient resin filling into the pipe joint portion 13 can be achieved. After the rear big 3 has passed, resin enters the branch opening of the branch pipe (supply pipe) 40 that communicates with the existing pipe 1, but in order to prevent this, one pressure air is supplied to the branch pipe 40 from the outside. The solder resin is blown into the branch port and the soldered resin is poured into the existing pipe 1.
release it inside. It is preferable that the released resin be smoothed onto the inner wall of the existing membrane tube 1 later by passing it through a copying machine or the like. When the repair of the pipe joint part 13 is completed, remove the clamp 82 and divide the lid into two parts by removing the lid, open the lid 1, first discharge the front resin C of the front big 2, and then Derive the rear big 3. Then, when the front pig 2 is uncoupled from the tow line 4, the big 2 is freed, and the winch 9 pulls the tow line 4, the front pig 2 does not move and only the rear big 3 moves inside the conduit 6. It climbs up. At this time, the residual resin is discharged from the discharge port 6a and collected into the container 41. In this case, since the lid 8 is split into two, the tow rope 4
Even if it is wound around the winch, the big 2゜3 and the cylinder 1
It does not get in the way of taking out item 4. Effects of the Invention As explained above, according to the pipe joint half repair device for an existing pipe according to the present invention, a flexible section is provided on the outer circumference of the tow cable 4 from the rear pig 3 to the front tow cable 4 over a predetermined length range. side 14 or jacket piece 14
By installing a, the length of the resin inside the existing resin pipe 1 can be increased to increase the resin pressure, and the resin filling time can also be extended, ensuring that the pipe joint 13 is filled with resin. In addition, even if the amount of resin supplied is reduced, the specified resin pressure can be obtained, so there is no need to supply excess resin, which reduces wasted resin and improves work efficiency. I can do it. Furthermore, the cylindrical body 14 or the outer cover piece 1
4a is the thickness depending on the diameter of the existing pipe 1. By appropriately selecting the length, it can be adapted to many types of tube bodies.

[Brief explanation of drawings]

Fig. 1 is a schematic side view of the entire repair device showing one embodiment of the present invention, Fig. 2 is a schematic side view showing a portion of a pipe for inserting a pig, and Fig. 3 is a schematic side view showing a portion of a pipe for leading out a pig. Fig. 4 is a vertical sectional side view showing the pig in a towed state, Fig. 5 is a side view showing another embodiment of the outer cover, and Fig. 6 is an E-E in Fig. 5.
7 is a side view showing still another embodiment of the jacket piece, and FIG. 8 is a sectional view taken along lines F- and -F in FIG. 7. 1...Existing pipe, 11.12...min mya, 13...
・Pipe joint part, 2... Front side big, 3... Back side pig, 4... Traction cable, 40... Branch pipe, 41... Container,
5...Vig insertion conduit, 5a...Resin injection port, 5
b... Exhaust port, 51... Clamp, 52.53
...cock, 54...cross bin, G...big outlet conduit, 6a...discharge port, 6b
...Air pressure supply port pipe, 61...Opening/closing cock, 7...Resin/person tank, 7a...Hose 1.7b
... Generator, IC ... Compressor, 8 ... Lid, 81 ... Guide reel, 82 ... Clamp, 9 ... Winch, 9a ... Drum, 10 ...
・Compressor, 10a...pressure operation unit, 14
... Cylindrical body, 14a, 14b... Outer cover piece, 15...
Locking member, 16... Wire rod A, B... Vertical hole, C, D... Resin. Patent applicant: Tokyo Gas Co., Ltd. Hatsuko Co., Ltd. Agent: Nobu Kobashi, patent attorney

Claims (1)

[Claims] Divide the existing underground pipe into repair units of a predetermined length and enter the existing pipe in the repair section from one separation opening.
A pig that slides in airtight contact with the inner surface of the tube is inserted with resin placed on the front side of the pig, and the pig is pulled by a tow rope to move the resin along the inside of the tube toward the other separation opening. In the process of filling the gaps between multiple pipe joints in the existing pipe, resin is applied to the outer periphery of the tow rope over a predetermined length range from the pig to the front, covering the outer periphery of the tow rope. A pipe joint repair device for an existing pipe, characterized in that an outer cover made of a flexible material is attached to make the pipe a large diameter.