JP2662972B2 - Repair method for fittings of existing piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention is to prevent water leakage by filling a repair resin from the inner surface of an existing pipe such as a water supply system or a sewer system buried underground in a buried state with a gap portion of a pipe joint from the pipe inner surface. The present invention relates to a method for repairing a pipe joint of an existing pipe.

[Prior art]

Conventionally, as a repair method for improving the sealing performance by filling a repair resin into a joint fitting space of an existing pipe laid underground using a pig, a rear-replaceable pig moved by a tow rope into the existing pipe. Is inserted, a repair resin is arranged on the front side of the pig, and the resin is filled in the gap of the pipe joint part by a displacement action when the pig passes through the pipe joint part while pushing the resin by the pig. The technology is known. The amount of the repair resin disposed on the front side of the pig corresponds to the number of pipe joints that are present in the repair target section when the pig is inserted into the existing pipe to start the repair work. An amount corresponding to the used amount is pooled and supplied, and the entire amount of the repair resin is replaced and filled into the gap of the pipe joint while being pushed by a pig.

[Problems to be solved by the invention]

In the above-mentioned conventional method of repairing a joint, the repair resin pooled in front of the pig is pressed by the pig, moves in the pipe, and sequentially fills the gap of the fitting in the process of moving. As the amount of resin gradually decreases, the working pressure of the resin on the pig is different immediately after the start of the repair work and immediately before the end of the repair work, and it is not possible to obtain a uniform repair state over the entire fitting to be repaired. If the repair resin with a short length is pooled in a lump, the curing reaction may start while being pushed by the pig, which has many restrictions on its use. The remaining resin discharged behind the pig is left in the pipe after passing through the pig, so that it is necessary to remove it immediately. The present invention has been made to solve the above problems,
The amount of resin for repair arranged in front of the pig is always almost constant, and the pipe joints in the repair section are repaired uniformly to prevent water leakage. It is an object of the present invention to provide a method of repairing a pipe joint part in which the excess resin discharged to the pipe can be discharged outside the pipe to shorten the working time.

[Means for Solving the Problems]

In order to achieve the above object, in the pipe joint repairing method of the present invention, a two-liquid curable resin supplied via a tube is mixed with a mixer and supplied as a repairing resin to the front side of the pig. A pressure sensor is provided at the front of the pig to detect a resin pressure generated by the flow resistance of the repair resin when the pig moves by the tow rope. Is controlled so that the amount of the resin for repair is always substantially constant. In addition, a swapper that moves with the pig is provided behind the pig, so that the remaining resin filled in the gap of the pipe joint portion and discharged to the rear of the pig is moved and discharged outside the pipe. is there.

According to the above-mentioned method, first, the amount of the repair resin pooled in front of the pig is always substantially constant, and the resin filling is performed under substantially the same conditions and in the same state for each joint in the repair section. By doing so, it is possible to reliably prevent water leakage, generation of red water, and the like, and even a repair resin having a short pot life can be treated before the curing reaction starts. Furthermore, the surplus resin discharged to the rear of the pig at the same time as the resin filling and repairing work of the pipe joint portion is discharged to the outside of the pipe, thereby shortening the construction period.

【Example】

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the figure, reference numeral 1 denotes an existing pipe (water pipe) to be repaired buried underground, and a long pipe is formed by connecting a cast iron pipe of a predetermined size by a pipe joint portion 2 by a conventional piping method. In the pipe joint portion 2, a gap occurs due to a change in a joint portion with a cast iron pipe due to a load of a vehicle passing on the pipe, an earthquake, or a soil layer change due to aging, or a component material of the joint portion. Because of deterioration or a cause of water leakage, a gap between the pipe joints 2 is filled with a repair resin P, which will be described later, from the pipe inner surface for the purpose of water leakage repair or preventive maintenance. In repairing the pipe joint portion 2, the existing pipe 1 is first divided into a repair section L having a length suitable for repair, and one of the separated ends 3 is connected to a work pit A having an opening above the ground, and the other is connected to a working pit A. Also exposed to work pit B, which also opened to the ground,
A pig insertion conduit 5 and a pig outlet conduit 6 are connected to 3 and 4, respectively. Then, a twin hose 7 to be described later is pulled out from the pig insertion conduit 6 through the pipe of the existing pipe 1 from the pig insertion conduit 5, and the tip of the twin hose 7 is wound by a winch 8 mounted on a work cart. The rear replacement type pig 10 attached to the end of the wire 9 provided in the twin hose 7 and the swapper 12 connected to the pig 10 via the wire 11 behind the pig 10 are towed. It has become. Since the pig 10 needs to be provided with a replacement function of filling the resin in the gap of the pipe joint portion 2 while excluding air, water, and the like interposed in the gap, the outer peripheral portion of the pig body that is in secret contact with the pipe inner surface is provided. On the left and right outer peripheral walls of the pig are formed resin introduction grooves 13 which are opened and opened in the traveling direction, and, in parallel with this, replacement grooves 14 are formed on the body upper and lower outer peripheral walls of the pig body. is there. These grooves 13 and 14 do not communicate with each other in the direction in which the pig travels, and overlap with each other in the circumferential direction. A pressure transducer 15 as a sensor for sensing and converting the resin pressure is provided on the resin contact surface at the tip of the pig 10, and the resin pressure converted by the pressure transducer 15 is supplied to the outside of the existing pipe 1. Lead 16 extends forward along the wire 9. A static mixer 17 is connected to the twin hose 7 at a fixed interval from the pig 10 via a wire 9 attached to a front side of the pig 10, and a resin supply chamber 18 is provided at a tip side of the mixer 17. , This resin supply chamber 18 is partitioned
A high-pressure tube 20 is connected to each of the divided resin supply chambers 18 at the front end thereof. The twin hose 7 is formed as a single piece in which the wire 9, the lead wire 16, and the high-pressure tubes 20, 20 are integrally wrapped by a flexible member, and is taken by the winch 8 as described above. ing. A work pump equipped with the winch 8 is provided with a resin pump 21 and a control device 22. The resin pump 21 is connected to separately send the two-liquid-speed curable resin to the high-pressure tubes 20, 20, and The control device 22 controls the resin delivery amount of the resin pump 21 based on the resin pressure sensed by the pressure transducer 15, and the resin length l of the pool resin P mixed by the static mixer 17 and supplied to the front side of the pig 10 is constant. Control so that On the other hand, a resin injection machine 23 mounted on a work cart is arranged near the work pit A, and a predetermined amount of resin is injected from the resin injection machine 23 into the front side of the pig 10 at the time of starting repair work. . In FIG. 2, reference numeral RP denotes a resin filled in the pipe joint portion 2, and p denotes an excess resin discharged to the rear of the pig 10. When performing repair work using the pipe joint repairing apparatus for an existing pipe having such a configuration, first, the twin hose 7 is inserted into the existing pipe 1, and the pig 10 is inserted as shown in the left end of FIG. And a two-liquid curable mixed resin is injected from a resin injection machine 23 as a pool resin P until the resin length becomes l.
10 and the swapper 12 move in the existing pipe 1 and push the pool resin P with the pig 10. While the pig 10 is moving in the pipe section, it only pushes the pool resin P. Since the resin pressure keeps a predetermined value, the control device 22 receives a signal from the pressure transducer 15.
Does not operate the resin pump 21. When the pig 10 passes through the pipe joint 2, the pool resin P
Is that air or water inside the pipe joint is discharged from the resin introduction groove 13 through the replacement groove 14 to the rear of the pig 10, and the filled resin RP is press-fitted into the gap of the pipe joint 2 at a predetermined pressure. At the same time, some surplus resin p discharged from the replacement groove 14 to the rear of the pig 10 moves while being collected by the swapper 12. The pressure of the pool resin P consumed by filling the pipe joint portion 2 with the resin decreases, and this change is sensed by the pressure transducer 15 and brought to the control device 22 by the lead 16 to the resin pump. Activate 21. The two-liquid curable resin from the resin pump 21 is sent to the resin supply chamber 18 through the high-pressure tubes 20 and 20 and mixed by the mixer 17 to form a pig.
Discharged in front of 10. When the resin length 1 of the pool resin P returns to the original value and the resin pressure reaches a predetermined pressure, the pressure converter 15 senses this and stops the operation of the resin pump 21 via the control device 22. By repeating such operations, the repair work of all the pipe joints 2 in the repair section L is completed, the pig 10 is taken out from the pig lead-out conduit 6, and the excess resin p collected by the swapper 12 is discharged out of the pipe. All work is completed.

【The invention's effect】

As described above, according to the method for repairing a fitting of an existing pipe of the present invention, the resin pressure of the repair resin disposed on the front side of the replacement pig is detected by the pressure sensor provided on the pig,
The amount of the two-liquid curable resin sent to the mixer was controlled based on this detection value, so that the repair resin always maintained a substantially constant amount, so that the pig moved from the start end to the end of the repair target pipe. The repair resin acts on the pig at a substantially predetermined pressure, and the pipe joints are filled with the resin under certain conditions to perform a reliable repair work, thereby reliably preventing leakage and generation of red water. In addition, since the resin is fed by being fed through a high-pressure tube in a state where two liquids are not mixed and mixed by a mixer, the residence time at the front side of the pig becomes extremely short, and the curing reaction hardly occurs, so that the resin is rich in quick curing. It is possible to use resin, and the working time and construction period can be shortened. In addition, at the same time that the pig fills the pipe joint with resin, the excess resin discharged behind the pig is collected by a swapper, so repair work and excess resin discharge work are completed in one process, shortening the construction period can do.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing an embodiment of a repair apparatus for carrying out the method of the present invention, and FIG. 2 is a side sectional view of a main part. 1 ... existing pipe, 2 ... pipe joint, 3, 4 ... separated end, 5 ...
... Pig insertion conduit, 6 ... Pig outlet conduit, 7 ... Twin hose, 8 ... Winch, 9 ... Wire, 10 ... Pig, 11 ... Wire, 12 ... Swapper, 13 ... Resin introduction Grooves, 14 ... Replacement grooves, 15 ... Pressure transducer (sensor), 16 ... Lead wire, 17 ... Static mixer,
18 ... resin supply chamber, 19 ... partition, 20 ... high-pressure tube, 21 ... resin pump, 22 ... control device, 23 ... resin injecting machine, A, B ... working well, P ... pool resin , P ... surplus resin, RP ... filling resin, L ... repair section.

Continued on the front page (72) Kunio Yamagami 2-5-1, Chuo, Ota-ku, Tokyo Ito Construction Co., Ltd. (72) Motoyuki Koga 1-9-18 Nakamachi, Meguro-ku, Tokyo (56) References Japanese Patent Application Laid-Open No. Sho 60-139991 (JP, A) Japanese Patent Application Laid-Open No. Sho 61-228195 (JP, A)

Claims (2)

(57) [Claims] 1. A pig of a rear replacement type, which is moved by a tow rope, is inserted into an existing pipe buried underground, a repair resin is arranged in front of the pig, and the resin is pushed by the pig. A method of repairing a pipe joint portion in which a resin fills a gap of the pipe joint portion by a substitution action when the pig passes through the pipe joint portion while the pig passes through the pipe joint portion. A curable resin is mixed by a mixer and supplied as a repair resin, and a pressure sensor is provided at the front of the pig to detect a resin pressure generated by a flow resistance of the repair resin when the pig moves by a tow rope. Adjusting the supply amount of the two-liquid fast-curing resin based on the detection value of the pressure sensor so as to control the amount of the repairing resin to be substantially constant at all times. 2. A rear part of the pig is provided with a swapper which moves together with the pig, so that the remaining resin filled in the gap of the pipe cut part and discharged to the rear of the pig is moved and discharged to the outside of the pipe. The method for repairing a pipe joint part of an existing pipe according to claim 1, wherein