JPH0722739B2 - How to repair the inner surface of an existing pipe - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention is intended for an existing pipe (gas pipe, water pipe, etc.) in a form in which a plurality of supply pipes leading to a demand destination are branched from a conduit line laid underground under a road or the like. The present invention relates to a method of repairing the inner surface of a pipe in a buried state.

[Prior art]

In general, the existing conduit pipes that are laid underground under a road or the like are laid with pipes in which cast iron pipes are connected by water pipe fittings. This type of conduit can cause leakage due to the load of vehicles passing on the road, the occurrence of earthquakes, and the like, resulting in gaps in the pipe joints and deterioration of the structural material due to deterioration over time. Therefore, for the purpose of repair or preventive maintenance, for example, as described in JP-A-60-139371, the pipe joint portion of the existing pipe is repaired from the inner surface of the pipe in the buried state. There is. Regarding the supply pipe branched from the conduit, since the pipe diameter is relatively thin and the wall thickness of the pipe is thin, corrosion holes are likely to occur in the pipe due to aging, and at the necessary time for leakage prevention and maintenance, The surface is being repaired with a resin lining.

[Problems to be Solved by the Invention]

In the above repair, the repair of the conduit is carried out such that the resin introduced into the conduit is advanced into the pipe by the pig and the gap of the pipe joint portion interposed in the conduit is filled with the resin. The problem here is that pressure can be applied from the front side in the traveling direction of the pig, for example, with pressurized air, so that the resin can be reliably filled into the gap of the pipe joint part, which causes the resin to flow into the conduit. When passing through the passage, a considerable amount of resin may enter the supply pipe at the branch portion of the supply pipe and block the supply pipe. As a countermeasure against this, it has been proposed to supply pressurized air from the terminal side of the supply pipe and discharge the invading resin into the conduit before the resin that has entered the supply pipe is cured. However, in this case, if the invading resin is still discharged into the conduit, the discharged resin may harden and become fluid resistance so as to narrow the inner diameter of the conduit. Before hardening, it is necessary to evenly smooth the inner wall of the existing pipe in the pipe. It is an object of the present invention to provide a pipe inner surface repairing method for an existing pipe, which can appropriately treat the invading resin without inviting such a complicated working procedure.

[Means for Solving the Problems]

Therefore, in the present invention, in the method of lining the inner surface of an existing pipe in which a plurality of supply pipes leading to a demand destination are branched from a pipe line laid underground under a road, etc. The first step of introducing a resin into the pipe from the end opening to the conduit path to subject the more branched supply pipe to the repair and subjecting the inner surface of the pipe to resin lining, and then introducing the conduit path into the pipe to repair The second step of repairing by advancing the resin by a pig to fill the resin in the gap of the pipe joint portion intervening in the pipeline or repairing the lining of the resin on the inner surface of the pipe is performed at the time of the second step or immediately thereafter. A suction force is applied to the inside of the pipe from the end opening of the supply pipe to the conduit, and the resin that has entered the pipe of the supply pipe from the branch port of the supply pipe in the second step is
The suction force is applied to the end side of the supply pipe, and the resin film formed in the first step is overlaid with a coating film of the intruding resin so that the resin is blown to the end side of the supply pipe. It is characterized by.

[Action]

According to the repair method as described above, when the repair is performed for the conduit, even if the resin moved by the pig enters the branch portion in the process of passing through the branch portion of the supply pipe, the end opening of each supply pipe A suction force is applied to the inside of the pipe reaching the conduit, and the invasion resin is sucked toward the terminal side of the supply pipe by the suction force and is applied while being superposed on the resin film formed in the first step. For this reason, when repairing the conduit, the resin penetrating into the supply pipe is also effectively used as a lining material in the supply pipe, and the workability can be improved. Further, after the inner surface of the conduit is repaired, it is not necessary to separately discharge the resin from the inside of the supply pipe into the conduit, or to even out the resin with a pig, so that the workability can be greatly improved.

【Example】

An embodiment of the present invention will be described below with reference to the drawings. In the figure, reference numeral 1 is a conduit line (main pipe) to be repaired that is piped under the road, and is a cast iron pipe of a predetermined size connected by a water pipe type joint portion 2. The supply pipe 3 leading to the front is branched and connected. In repairing the pipe joint portion 2 of the conduit line 1 and lining the inner wall of the pipe with resin, the conduit line 1 is used in the present invention.
Is first divided into repair sections L each having a length (for example, 100 m) suitable for repair, and both ends are opened. For this purpose, the vertical hole A
And B are excavated to expose the seam portions 1a and 1b of the conduits in the vertical holes A and B, and the seam portions are separated. Then, the inside of the conduit 1 is scavenged by utilizing the openings 26, 27 at both ends. At this time, the supply pipe 3 branched from the conduit line 1 is disconnected at the end of the meter attachment portion or the like, and the working port is opened here (see FIG. 1). Then, using the compressor 40, the resin supply device 41, etc., the liquid resin is introduced into the opened supply pipe 3 from the open end, and the resin is sent by blowing air,
A resin lining is applied to the inner surface to prevent leakage due to pinholes, corrosion holes, etc., and repair such as reinforcement against material deterioration (see FIG. 2). The excess resin discharged into the conduit 1 at the time when the resin lining for the supply pipe 3 is completed is discharged to the outside from one opening by a swapper pig (not shown) passed through the conduit 1. . Thereafter, a pig insertion launcher 5 and a pig lead-out launcher 6 which will be described later are connected to the openings 26 and 27 (third part).
See figure). The launcher 5 has an opening through the clamp 25.
26, the launcher 6 is connected by a flange connection utilizing the existing flange portion. Then, from the launcher 5 for pig insertion, the tow cable 4 is passed through the conduit path 1,
This is pulled out from the pig launcher 6 and wound on the winch 9. A pair of front and rear pigs 7 and 8 are attached to the tow line 4 and are drawn into the conduit path 1 from the pig inserting launcher 5. In this case, the front pig 7 is provided with fins 7a on the outer circumference. The resin C on the front side is distributed in front of the rear pig 8 through the gap formed by the fin 7a. In this case, in the pipe joint portion 2, the resin C is filled when the pig 7 passes through the gap 2a. The rear pig 8 is also provided with a fin 8a on the outer periphery thereof, and a primary lining a is applied to the inner wall surface of the pipe through a gap in the outer peripheral portion of the pig 8 formed thereby. Further, in order to introduce the resin C to the front side of the pig 7, the insertion launcher 5 is provided with a resin filling port 5a, and the resin filling port 5a is connected from the tank 10 via the hose 11
Resin C is supplied via the cock 12. At the time of this supply, in order to draw out the resin C from the tank 10, a generator
Pressure air is supplied to the tank 10 from a small compressor 13 driven by 28. In order to prevent the pigs 7 and 8 from coming out of the inlet end of the launcher 5 due to the filling pressure of the resin C, after the pigs 7 and 8 enter the launcher 5, the cross pin 14 is attached to the inlet end of the launcher 5. Good to do. Further, as shown in FIG. 4, the pipe joint portion 2 to be repaired is, for example, a large-diameter portion 2a provided at one pipe end, but the other pipe end 2b is abutted against the fitting portion, It has a structure in which a sealing material 15 called “hemp skin” is packed and the opening is plugged with a lead material 16. The pig insertion launcher 5 has the resin filling port.
At a level slightly higher than 5a, an exhaust port 5b is provided, and a cock 17 is provided here. Further, the pig lead-out launcher 6 has a discharge port for discharging residual resin.
6a is provided, and a cock 18 is provided there. Above the discharge port 6a, the pig lead-out launcher 6 is provided with an air pressure supply port pipe 21 that communicates with the compressor 19 and the pressure operation unit 20. Further, a lid 23 having a guide reel 22 for guiding the tow line 4 passing therethrough to the drum 9a of the winch 9 is detachably attached to the launcher 6 via a clamp 24. Then, the resin C on the front side of the pig 7 introduced into the conduit line 1
Is a process in which the pigs 7 and 8 move forward by the force applied to the tow line 4,
In a state where the pressure of the pressurized air given from the air pressure supply port pipe 21 is received, the pig 8 is pushed along the inner wall of the conduit passage 1 to move forward. When reaching the pipe joint portion 2, the resin C
Based on the applied pressure of the pressurized air and the viscous resistance generated between it and the pipe wall during the movement process, the resin C has a required filling pressure at the rear end of the nodule, so that it is passed through the outer circumference of the pig 7. It flows into the gap 2 a of the pipe joint portion 2. On the other hand, the gap of the pipe joint 2
From 2a, the air staying there is expelled rearward as the resin C is introduced. In this way, the pipe joint 2
The air is replaced with resin. In addition, the resin C passing through the outer periphery of the pig 7 in front of the rear pig 8.
Is supplied to the inner wall of the pipe to perform a primary lining on the outer periphery of the rear pig 8. In this way, when the pigs 7 and 8 pass through the branch point of the supply pipe 3 in the process of passing through the inside of the conduit line 1, a part C ′ of the resin C enters into the supply pipe 3. Therefore, in the present invention, after the rear pig 8 has passed through the branch point, the vacuum pump 29 is connected to the outer end of the supply pipe 2 via the pressure regulating valve 30 and the cock 31 as shown in FIG. , A required suction pressure is generated in the supply pipe 2 before the resin C ′ is cured. The resin C ′ that has entered the supply pipe 2 by this suction pressure is overlaid on the resin lining layer a already formed on the inner surface of the supply pipe 2 to form a lining layer a ′ as shown in FIG. It is drawn into the supply pipe 2. However, when the lining layer a'is gradually reduced in the process of forming, the resin C'will eventually blow out as shown in FIG. It is effectively consumed as a lining layer. When the repair of all the pipe joint portions 2 and the primary lining in the conduit 1 are completed, the clamp 24 is removed, the lid 23 is removed, the front side pig 7 is taken out first, and the connection between the pig 7 and the tow line 4 is removed. It is released to make the pig 7 free, and the winch 9 pulls the tow line 4 to guide the pig 8. On the other hand, when the cock 18 is opened and placed, the residual resin is discharged to the container 32. In the same way as in the case of Pigs 7 and 8 above, as shown in Fig. 8,
The pig 7'and the finishing pig 8'for the secondary lining a "are then passed through the tow line 4'into the conduit line 1. At this time, suction is maintained in each supply line 2. Then, after the secondary lining a ″ (performed in the same manner as the above-mentioned primary lining) is performed in the conduit line 1, the finishing pig is inserted and the work is completed. The final treatment is the same as for the primary lining.

【The invention's effect】

The present invention has been described in detail above, and the inside of the supply pipe is preliminarily resin-lined in the first step, and then in the second step, the pipe joint portion of the conduit is repaired and the inner surface of the conduit is resin-lined. In this case, even if the resin enters the supply pipe at the branch point of the supply pipe, it is introduced into the supply pipe by suction, and is consumed in the form of being lined by overlapping on the lining layer to blow out the invading resin. Compared with the conventional method, there is no need to pass a leveling pig for post-treatment in the conduit, and work efficiency can be improved, and the resin penetrating the supply pipe is layered on the lining layer. It will be used effectively.

[Brief description of drawings]

FIG. 1 is an overall schematic view showing a state before construction showing an embodiment of the present invention, FIG. 2 is a schematic view showing a mode for carrying out resin lining on an inner surface of a supply pipe, and FIG. 3 is a pipe joint portion and FIG. 4 is an explanatory view showing a pig insertion state at the time of primary lining, FIG. 4 is an enlarged cross-sectional view of a pipe joint portion, FIG. 5 is a schematic view showing a construction state for treating invading resin in a supply pipe, FIG. 6 and FIG. 7 is an enlarged cross-sectional view of the main part of the same, and FIG. 8 is an explanatory diagram showing a pig insertion state at the time of secondary lining. 1 ... Pipeline, 2 ... Pipe joint, 3 ... Supply pipe, 7 ...
Pig, 8 ... Pig, 29 ... Vacuum pump, 30 ... Pressure adjusting valve, 31 ... Cock, C ... Resin.

Front Page Continuation (72) Inventor Kazuyasu Takeuchi 4-18, Ltd., Hakko Development Technology Research Institute, 3-18 Daikan City, Kanagawa Prefecture

Claims (1)

[Claims] 1. A method of lining and repairing an inner surface of an existing pipe in which a plurality of supply pipes leading to a demand destination are branched from a pipe line laid underground under a road, etc. The first step of introducing the resin into the pipe that reaches the conduit from the end opening of the supplied supply pipe and subjecting the inner surface of the pipe to resin lining, and the resin introduced into the pipe after the conduit is repaired The second step of repairing by filling with a resin in the gap of the pipe joint portion which is advanced by a pig to intervene in the pipeline or lining repair of the resin on the inner surface of the tube, and at the time of the second step or immediately after that, each supply pipe A suction force is applied to the inside of the pipe from the end opening of the supply pipe to the conduit, and the resin that has entered the supply pipe from the branch port of the supply pipe in the second step is sucked toward the end side of the supply pipe by the suction force. Shape during process On the resin film, construction inner surface repairing method of the existing pipe, characterized in that so as to blow the resin at the end side of the supply pipe while forming overlapping a coating film by intrusion resin.