JPS58193776A - Repairing method of inside surface of installed pipe - Google Patents

Abstract

PURPOSE:To easily execute the repair of coating of a necessary route part from the ground, by using the end part of a specified feed pipe as a coating material feeding part and a vacuum suction part, when coating and repairing the inside surface of an existing pipe such as a gas pipe, etc. comprising a branch pipe from which many underground feed pipes are banched. CONSTITUTION:When repairing the inside surface of an existing pipe such as a gas pipe, etc. comprising a branch pipe 30 from which many feed pipes 31, 31a are branched, by coating it with a thermosetting resin, the inside of the pipe is cleaned by a polishing material in advance, and also is heated and dried. Subsequently, a coating material feeding head 8 is connected to a necessary feed pipe 31 among many feed pipes 31, and a vacuum pump 23 is connected to the end of other necessary feed pipe 31a through a collecting vessel 20a. High- temperature vortex carrier air to which a coating material is added is fed from the head 8, is sucked by the vacuum pump 23, and a necessary part of the feed pipes 31, 31a and the branch pipe 30 is repaired easily from the ground by coating the inside surface.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for repairing the inner surface of existing gas pipes, water pipes, etc. when coating the inner surface with a resin agent.
Illll.

Conventionally, various methods have been proposed to repair underground pipes or indoor pipes such as gas pipes and water pipes from the inside. One of these methods is to use a coating agent of thermosetting resin such as epoxy resin There is a method in which the material is placed on a carrier gas and transported into the target a-membrane tube, where it adheres to the inner wall surface and solidifies.

In this case, the problem is that one group of the existing pipe system has a large number of underground supply pipes branching off from branch pipes. For this reason, even if the coating agent is diffused into the carrier gas and sent into the existing pipe from the opening at one end of the branch pipe, it is often impossible to reliably coat the entire branch pipe or the supply pipe. This is likely to occur in vent parts, 9-way junctions, inside narrow supply pipes, etc., where flow resistance is large.

In addition, existing pipes are used every day, so
It is impossible to suspend use for a long period of time for repair work, and there are severe restrictions on the working hours per day, so it is necessary to be able to carry out repair work efficiently.

The present invention has been proposed in light of the above circumstances, and uses negative pressure suction to establish a fixed distribution route for the carrier gas in the existing piping system, thereby ensuring that the coating process is carried out within this route. It is an object of the present invention to provide a method for repairing the inner surface of an existing pipe, which enables the repair work to be carried out efficiently from the surface of the existing underground pipe.

For this purpose, in the coating process, the above-mentioned coating process uses an above-ground connection part at the end of a required supply pipe among a plurality of supply pipes branched from a branch pipe as an opening, from which the supported gas and the coating diffused therein are provided. The above-mentioned carrier gas is introduced by using the above-ground connection part at the end of the other required supply pipe as a second opening by negative pressure suction force, so that the inside of the existing underground pipe can be coated from above ground. It is characterized by the following.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a description will be given based on illustrated embodiments embodying the construction method of the present invention.

First of all, Figure 1 shows the overall outline and causes, and in the figure, reference numeral 1
is a compressor, and its compressed air outlet [1 side is connected to header 2]. The header 2 is connected to an air heater 4 via a governor 3, and the air heating $4 is a mixture of steam supplied from the boiler 5 via the pressure reducing valve 6 and compressed air from the header 2. For example, 0.3
A carrier gas with a low positive pressure of about kQ/(j12 is generated. The carrier gas is brought to the resin coating head 8 via the airflow generator 1 in a desired airflow form, for example, a vortex. , the air heater 4 flows heated air to the coating head 8 via a bypass path 9; in the bypass path 9, a thermosetting resin such as an epoxy resin is used as a coating agent; For example, the coating agent is supplied from the tank 10.The coating agent can be supplied from the tank 10 to the bypass path 9 by dropping a drop into the heated air or by spraying it.In this embodiment, the pressure regulator 11 A method is adopted in which the coating agent is injected from inside the tank 10 through a valve 10a by the pressure of compressed air supplied from the header 2 through the tank 1.
The viscosity is lowered to an appropriate level.

In FIG. 1, reference numeral 13 is a safety valve provided downstream of the governor 3, 14 is a flow meter, 15 is a pressure gauge, and 16 is an all meter.

Further, in this embodiment, an abrasive charger 17 is communicated downstream of the airflow generator 1 via a valve 18, and compressed air is also supplied to the charger 17 from the header 2. When the valve 18 is opened, the abrasive can be supplied downstream of the airflow generator 1 with the compressed air.

The coating head 8 is connected to the existing pipe to be repaired. As shown in the embodiment shown in Fig. 2, A has a configuration in which a large number of supply pipes 31 are branched from a branch pipe 30 buried underground, and the ends of the supply pipes 31 are exposed above ground and are connected to each home. This is similar to a gas meter, etc.

For such an existing pipe A, in the present invention, among the plurality of supply pipes 31 branched from the branch pipe 30, the above-ground connection part (the connection part with the gas meter) at the end of the required supply pipe 31 is used as an opening. The coating head 8 is connected to this via a conduit to serve as an introduction section for a gas carrying a coating agent. In addition, the ground connection at the end of the other required supply pipe 31a is used as a second opening, and this opening has a
A coating agent recovery @ 20a and an abrasive etc. recovery device 20b are connected via a conduit 19 having valves 21a, 21b, and further the recovery devices 20a and 20b are connected to each other.
A vacuum pump 23 is connected via a conduit 22 downstream of the . It should be noted that this vacuum pump 23 performs a suction action on the existing pipe A at a low negative pressure of, for example, about 0.3 kg/cs2.

Next, repair of the inner surface of the existing pipe A will be explained step by step.

First, in the process of driving the compressor 1 and the vacuum pump 23 and supplying heated carrier gas (pressurized air) to the head 8 via the air heater 4, the valve 18 is opened and the pressure is increased via the pressure regulator 11. The abrasive is introduced into the carrier gas from the injector 11 with the air pressure adjusted accordingly. When the injected abrasive passes through the existing pipe A on a vortex generated by the airflow generator 7 against the carrier gas, it scrapes off sludge, rust, etc. in the existing pipe A, and removes this from the carrier gas. and lead it to the conduit 19. The pulp 21b is open, and these dusts are collected together with the abrasive in the collector 20b.

Once the inner surface cleaning of the existing 1A is completed, pulp 18
is closed, the supply of abrasive to the carrier gas from the injector 11 is cut off, and only the carrier gas is allowed to pass through the existing pipe A. Since the carrier gas is heated by the air heater 4, it heats the inner wall of the existing pipe A, evaporates moisture, etc., and makes it dry.

Next, the pulp 10a is opened, the pulp 21b is closed, and the pulp 21a is opened. As a result, the coating agent is sprayed onto the air flow passing through the bypass path 9 using the air pressure adjusted via the pressure regulator 11, and is made into a mist, for example. The airflow with the coating agent dispersed in this way is brought to the coating head 8 and introduced into the existing pipe A while being carried by the compatible gas. A resin film 8 is formed on the surface.

In this case, in the present invention, as described above, the above-ground connection part at the end of the supply pipe 31 is used as an opening, and the coating head 8 is connected to this opening to serve as a gas introduction part, and the above-ground connection part at the end of the other supply pipe 31a is used as an opening. Since the compressor 1. is configured as a second opening and the recovery device and the vacuum pump 23 are connected to this opening via a conduit, the compressor 1. When the vacuum pump 23 or the like is driven, the suction force by the vacuum pump 23 is
Since a unidirectional suction force is applied to the supply pipe 31, the suction action causes the coating agent to flow from the above-ground connection at the end of the supply pipe 31 through the supply pipe to the branch pipe 30 on the carrier gas. , further flows through a part of the branch pipe 30 to another supply pipe 31 . In this way, the gas carrying the coating agent by suction force is transferred to the existing pipe A.
Since the liquid reliably flows through the pipe along the desired route, the inside of the pipe along that distribution route can be reliably coated.

Note that in the above embodiment, a plurality of supply pipes 31 branching left and right around a branch pipe 30 are coated in a one-to-one relationship, but even if a plurality of supply pipes are coated at the same time. good.

In addition, in the above embodiment, the supported gas is supplied into the existing pipe with low positive pressure applied, and is sucked into the required route by applying low angular pressure. Preheating with a carrier gas can also be performed when repairing the inner surface of existing pipes. Alternatively, the method may be such that only positive pressure or negative pressure is applied to the supported gas.

As described in detail above, the present invention involves transporting a coating agent into an existing pipe in a state in which it is diffused in the flow of a carrier gas, adhering and solidifying the coating agent to the inner wall surface of the existing pipe, and branching out from a branch pipe when repairing the inner surface. Among the plurality of supply pipes, the above-ground connection at the end of each required supply pipe is used as an opening to introduce the carrier gas and the coating agent diffused therein, and the above-ground connection at the end of the other required supply pipe is used as an opening. Connect the second
Since this is a construction method in which the above-mentioned supported gas is drawn out by negative pressure suction through the opening, the following effects can be obtained.

(1) Even in existing pipes that are complicated and branch out, the direction of gas flow within the existing pipes is regulated to a constant level, so the coating process within the pipes can be reliably performed along the desired route of construction.

0) In addition, the above-ground connection at the end of the supply pipe is used as an opening, and this opening is used as an inlet and an outlet for the carrier gas and coating agent. In order to distribute the carrier gas to the above-ground part, there is no need to dig up the existing underground Q-ft, and repair work on the inner surface of the pipe can be performed from above the ground, so construction can be performed easily and efficiently.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of the method of the present invention, and FIG. 2 is a diagram showing a construction mode. 1... Compressor, 4... Air heater, 7...
Airflow generator, 8... Coating head, 10...
Tank, 23...vacuum pump.

Claims (1)

[Claims] The coating agent is transported into the existing pipe in a state in which it is diffused in the flow of compatible gas, and adheres to the inner wall surface of the existing pipe. When solidifying and repairing the inner surface, the existing underground pipe system targets a branch pipe underground and multiple supply pipes branching from it. The above-ground connection at the end of the pipe is used as an opening through which the carrier gas and the coating agent diffused therein can be introduced, and the above-ground connection at the end of the other required supply pipe is used as a second opening for vacuum suction. A method for repairing the inner surface of an existing pipe, characterized in that the inside of the existing pipe buried underground can be coated from above ground by drawing out the supported gas by force.