JPS58193774A - Repairing method of inside surface of installed pipe - Google Patents

Abstract

PURPOSE:To diffuse a coating material in a carrier gas, and to raise a coating effect, by adding the coating material to a high-temperature carrier gas swirled to form vortex, when repairing the inside surface of a pipe by feeding the coating material into an existing pipe such as a gas pipe, etc., by the carrier gas. CONSTITUTION:Compressed air generated by an air compressor 1 is heated by the high-temperature steam from a boiler 5, is made to a vortex flow by an air current generator 7, and there after, a grinding material from a tank 17 is added, and it is passed through an existing pipe A such as a gas pipe, etc., by which the inside surface is cleaned. Subsequently, only heated carrier air is fed, the inside surface of the pipe is heated and dried, and thereafter, a coating material of a thermosetting resin is added to the heated carrier gas passing through a by-pass 9, from a tank 10, and it is added into the carrier gas which passes through the air current generator 7 and becomes a vortex, by a head 8. The coating material is diffused by the vortex carrier gas, goes into the existing pipe A, and forms a uniform coating layer B on the inside surface of the pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for repairing the inner surface of existing gas pipes, water pipes, etc., when the inner surface of the pipe is coated with a resin.

Conventionally, various methods have been proposed for repairing underground first-tier pipes or indoor piping, such as gas pipes and water pipes, from the inside.One of these methods is coating with thermosetting resin such as epoxy resin. There is a method in which the agent is placed on a compatible gas and transported into the target existing pipe, where it adheres to the inner wall surface and solidifies.

In this case, the key issue is how well the tinging agent can be diffused when introduced into the carrier gas. This is clear from the graphs in FIGS. 2 to 4. In other words, the table in Figure 2 shows the relationship between the viscosity of the coach ink agent and the mist concentration (here, the degree of dispersion of the coating agent in the carrier gas). This shows that it can be enhanced. The table in FIG. 3 shows the relationship between the mist concentration and the distance traveled by the mist, and the table in FIG. 4 shows the relationship between the distribution of mist particles depending on the distance traveled. From these results, it can be seen how well diffusing the coating agent into the carrier gas and making it fine particles can extend the length of transport by the carrier gas. This effect is particularly great when the supported gas is at low pressure.

The present invention was made based on the above circumstances and is an IC device in which a coating agent is placed on a carrier gas and sent into an existing pipe.
When it adheres to the wall surface in the existing pipe and is 311 controlled, by placing the coating agent on the carrier gas in the latter stage of generating the airflow applied to the carrier gas, the kinetic energy of the flow is absorbed in the form of the airflow of the carrier gas. The present invention aims to provide a method for repairing the inner surface of an existing pipe in which a coating agent is more effectively diffused into a carrier gas and the particles are made finer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of the present invention will be explained below based on illustrated embodiments embodying the method. In FIG. 1, reference numeral 1 denotes a compressor, whose compressed air outlet side is communicated with a header 2. As shown in FIG. The header 2 is connected to an air heater 4 via a governor 3, and the -1st air heater 11A4 is connected to the steam supplied from the boiler 5 via the pressure reducing valve 6 and the compressed air from the header 2. For example, 0.3 kg/c
This generates a carrier gas with a low positive pressure on the border of w2. 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. On the other hand, 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, and a resin injection means, For example, it is supplied from a tank 1o. For supplying the coating agent from the tank 1o to the bypass path 9, a method of dropping droplets into heated air or a method of spraying can be adopted. In this embodiment, a method is adopted in which the pressure of compressed air supplied from the header 2 via a pressure regulating gill is used to inject air from inside the tank 1o via a valve 10a.

Further, the coating agent is heated in the tank 10 by an electric heater 12 to lower the viscosity to an appropriate level.

In the figure, reference numeral 13 indicates a safety valve provided downstream of the governor 3;
14 is a flow meter, 15 is a pressure gauge, and 16 is m degrees i1.

Furthermore, in this embodiment, an abrasive charger 11 is connected downstream of the airflow generator 7 via the pulp 18, and compressed air is also supplied to the charger 11 from the header 2. When the pallet 118 is opened, the abrasive can be supplied downstream of the airflow generator 1 with the compressed air.

The coating head 8 is connected to an opening at one end of the existing pipe A (target existing pipe system including branch pipes and supply pipes) to be repaired by a conduit, and a conduit is connected to the opening on the opposite side of the existing pipe A. Coating agent recovery device 20 via 19
Recovery of a and abrasive @ 20b is pulp 21a
and 21b. And the recovery device 2
0a and 20b are further connected via conduit 22 to a vacuum pump 23. The above-mentioned vacuum pump can be applied to existing pipes, for example, -0.3kg/cg+2
It applies a moderately low negative pressure to create a suction effect.

As shown in FIG. 5, the airflow generator 1 has a configuration in which the spiral blades 7b are arranged and fixed in the cylindrical main body 1a, or the spiral blades 7b are driven to rotate by a required power. good. In this embodiment, the spiral 117b is fixed, and the flow pressure of the carrier gas passing therethrough provides a swirling flow.

As shown in FIG. 6, the airflow generator 5 is configured to generate a vortex by rod-shaped (or plate-shaped) deflectors 7b randomly arranged within a cylindrical main body 7a. Good too. As a result, within the existing pipe A,
Karman vortex flow is generated near one surface inside the tube.

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 supplied via the pressure regulator 11. 1. The abrasive is introduced into the carrier gas from the injector 11 at the adjusted air pressure. When the injected abrasive passes through the existing pipe A on the vortex generated by the airflow generator 1 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 1119. The valve 21b is open, and the dust is collected together with the abrasive in the collector 20b.

When the inner surface WIi inside the existing pipe A is completed, the pulp 18 is closed, the supply of fA abrasive from the injector 11 to the carrier gas is cut off, and only the carrier gas is passed into the existing pipe A. Since the carrier gas is heated by air heating @ 4, the inner wall of the existing pipe A is heated to evaporate and remove moisture etc., thereby making it dry.

Next, valve 10a is opened, valve 21b is closed, and valve 21a is opened. As a result, the tinging agent is injected into the air flow passing through the bypass 9 at the air pressure adjusted via the pressure regulator 11, for example, in the form of a mist.

The airflow with the coating agent dispersed in this way is brought to the coating head 8, carried on the carrier gas and introduced into the existing pipe A, and the coating agent collides and adheres to the inner wall of the pipe by the swirling or swirling flow. Tokoro I! A resin coating with a thickness of 11B is formed.

In this case, the coating agent is then dispersed in an air stream to create an atmosphere, which is introduced into the coating head 8 against the carrier gas in a swirling or swirling airflow situation. Due to the kinetic energy of the air flow, the coating agent is dispersed in the carrier gas, and the coating agent is made into finer particles. As a result, the conveyance distance within the existing pipe A is increased to [person rl].

In the above embodiment, low positive pressure is applied to the supported gas on the inlet side to supply it into the existing pipe, and low negative pressure is applied on the outlet side to suck it into the desired route. Preheating with a carrier gas can also be used when repairing the inner surface of existing pipes using positive or negative pressure. Alternatively, a method may be used in which only positive pressure or negative pressure is applied to the supported gas.

In the above embodiment, the coating agent was firstly diffused in the bypass path 9 and then re-diffused in the coating head 8, but it was also injected directly from the tank 10 into the compatible gas in the coating head 8. Good too.

As described in detail above, the present invention allows the coating agent to be transported into the existing pipe in a state of being diffused in the flow of the carrier gas, and to be attached to and solidified on the inner wall surface of the existing pipe. Since the tinging agent is diffused into the flow of the carrier gas in the subsequent stage of generating the flow, the following effects can be obtained.

(1) Since the coating agent is finely granulated and transported in a compatible gas, the transport distance is longer than when it is passed through existing pipes in liquid form, and the film formed by the coating agent is uniform and relatively thin. can.

(2) Since the coating agent is diffused in an airflow state such as a swirling flow or eddy flow generated in the supported gas, better diffusion can be achieved by the kinetic energy of the airflow,
The subsequent transport by the carrier gas is good, and the transport distance can be extended.

(3) Since the coating agent does not enter the means for generating airflow (airflow generator), it is easy to clean up the means when cleaning the said means later.

(4) Carrier gas and coating agent are heated separately III
When the coating agent is diffused into the carrier gas, the dispersed particles of the coating agent can be introduced into the existing pipe under optimal temperature conditions.

[Brief explanation of the drawing]

Figure 1 is a schematic configuration diagram of an example embodying the method of the present invention, Figure 2 is a chart showing the relationship between the viscosity of the coating agent and the viscosity of the mist, and Figure 3 is the mist concentration and the distance traveled by the mist. FIG. 4 is a chart showing the relationship between the mist particle size distribution depending on the reaching distance, and FIGS. 5 and 6 are perspective views showing specific examples of the airflow generator. 1...Funpuretsuri, 4...Air heating machine, 1...
Air flow generator, 8... coating head, 9... bypass path. Patent applicant Hatsuko Co., Ltd. Patent attorney Jundo Kokai Patent attorney Ichiban Susumu Mura

Claims (1)

[Claims] The coating agent is transported into the existing pipe in a state where it is diffused in the flow of the carrier gas, and adheres to the inner wall surface of the existing pipe. A method for repairing the inner surface of an existing pipe, characterized in that during assimilation, the coating agent is diffused into the flow of the supported gas at a subsequent stage of causing a predetermined flow of the coating agent in the supported gas.