JPS6223627B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for lining the inner surface of a pipe.

As a method of lining the inner surface of existing pipes such as water supply pipes and drainage pipes in structures such as buildings, an epoxy resin paint mixed with a base agent and a hardening agent is supplied to one end of the pipe to be treated, and at the same time pressurized gas is sent in. A method has already been proposed in which this paint is moved through the pipe and coated on the inner surface of the pipe.

Even in this method, the paint is dispersed in a mist using pressurized gas, or for example,
As seen in No. 94670, there are some that give pressurized gas a swirling flow before sending it out, causing the paint inside the pipe to move while moving through it.
In either case, pressurized gas is used as a means of transporting the paint within the pipe to be treated, so the paint does not scatter or swirl sufficiently within a range of 2 to 4 meters from the starting end of the pipe to be treated. There is a drawback that the inner surface of the pipe cannot be coated reliably.

In addition, in the conventionally known lining method,
As shown in the conceptual diagram in Fig. 1, apart from the air compressor 1' as a pressurized gas source, there is also an air compressor 1' that mixes the main component of the paint and a curing agent and pumps the mixed paint to the pipe 2' to be treated. A liquid type airless paint sprayer 3 and its pressure feed hose 4 are essential, and these must be carried to the work site and set up each time, and after lining is completed, the paint adhering to the airless paint sprayer and hose is washed and removed with thinner. This required work to be done and carried out, making it impossible to improve efficiency in terms of manpower, time, and efficiency.Moreover, since an expensive airless coating machine was used, no reduction in lining costs could be expected at all.

Furthermore, when mixing the base agent and curing agent using the two-component airless paint machine, if a mixing error occurs due to clogging or backflow, the epoxy resin paint that has been lined with the paint will be pumped into the pipe and the lined epoxy resin paint will be mixed. In addition to the possibility of problems with not curing, as mentioned above, the paint adhering to the equipment must be washed off with thinner, so the time it takes for the paint to harden is at most 2 hours after lining is completed (20 ℃), and it is impossible to shorten the time any further, for example, to about 30 to 40 minutes.

If the paint has a high viscosity of 10,000 CP or more, it is extremely difficult to pump the paint with a conventional two-component airless paint sprayer due to the pressure resistance of the hose. Since paint is used, the thickness of the inner coating of the pipe to be treated remains at around 0.5 mm, and it was not possible to increase the thickness to 1.0 mm.

The present invention aims to solve all of the above-mentioned problems, and does not require any airless atomizers or paint pressure hoses that are commonly used in the conventional methods described above, and can reliably line the inner surface of the pipe. The purpose is to provide a simple method to obtain.

FIG. 2 schematically shows an embodiment of the present invention. This will be explained below. Reference numeral 5 designates a trap pipe for pumping paint, one end of which has a filling port 5a with a slightly larger diameter. A closing lid 6 is attached to the other end 5b, and this end 5b is inserted into one open end of the pipe 2 to be treated and sealed with the lid 6.

Next, the main ingredient of the epoxy resin paint and the curing agent are mixed manually using, for example, a measuring cup, and the paint P is injected into the trap pipe from the filling port 5a. Is the filling amount equivalent to the amount calculated from the diameter and length of the pipe to be treated?
Or slightly more.

Immediately after filling, the filling port 5a is sealed with the lid 7, the air hose 8 of the compressor 1 is connected to the filling port 5a, and the compressor 1 is operated to supply compressed air at a predetermined pressure to the filling port 5a. Continuously feed into the inside of. In this case, the pressure in the pipe to be treated 2 is as shown in FIG.
The conditions must be set so that the air volume is generated such that the wind speed is smaller than the scattering limit value (vector A) caused by the viscosity of the paint P used, and larger than the viscosity or potential energy (vector B). becomes.

When pressurized gas is continuously fed into the trap tube 5 in this manner, the paint P inside the tube undergoes a rapid change as shown in FIG.

In other words, since considerable frictional resistance is generated throughout the portion of the paint P that is in contact with the inner wall surface of the trap tube, the entire paint P will not be pushed out even if the internal pressure of the filling port 5a increases. However, when this internal pressure increases to a certain extent, the trap pipe 5 shown in FIG.
In the straight pipe portions 5c, 5d, and 5e of the trap pipe 5, the resistance is the least at a position approximately along the center line of the pipe, and in the bent portions 5f and 5g of the trap pipe 5, the entire body is placed at a position slightly offset from the center line of the pipe. As a result, a continuous small through hole 9 for pressurized gas is formed in a meandering state (fourth hole).
), the pressurized gas flows out into pipe 2. At this time, considerable frictional energy is generated on the pressurized gas contact surface P' of the through hole 9 due to the wind speed.
The surrounding paint P also flows out at the same time.

Once the through hole 9 is formed in the paint layer P in this way, it rapidly expands due to the synergistic effect of the pressure of the pressurized gas and the wind speed (Fig. 4), and the through hole 9 is formed on the contact surface P' of the paint layer P. is a pressurized gas passing through it, i.e. frictional energy is subsequently generated due to its wind speed,
Since the energy receiving pressure area is small, the paint around the hole only flows out and does not move as a laminar flow.

Thereafter, when the through hole 9 is further expanded (FIG. 4), the contact surface P' is also expanded, increasing the pressure area for receiving frictional energy due to the wind speed of the pressurized gas, and the paint P receiving this frictional energy. is in a laminar flow state, and since the pressurized gas holes 9 are formed in a meandering manner as described above, non-uniform moving energy is applied to continuous cross sections of the paint layer.
The paint layer moves from the trap tube 5 into the pipe 2 while automatically causing a swirling movement in one direction.

In this way, the swirling flow is caused and the pipe to be treated 2
As mentioned above, the paint P that has entered the interior is given a wind speed that is smaller than the scattering limit value of the paint and larger than its viscosity or potential energy, so it receives the frictional energy (vector C in Figure 3) and turns. It moves while continuing its motion, and forms a coating film uniformly not only on the upper inner surface of the pipe, but also on the entire inner surface of the pipe. Note that this swirling motion causes some disturbance at the elbow portion of the pipe 2, but it has been confirmed that after this, the pipe 2 moves again in a swirling motion. When the remaining paint drips from the terminal end of the pipe 2 to be treated, the lining is completely completed.

As mentioned above, in the lining method of the present invention, paint is sealed in a trap pipe connected to the pipe to be treated, pressurized gas is sent in, and the pressure is used to form holes for the pressurized gas in the paint layer. Once the through holes are formed, the wind speed generates frictional energy on the pressurized gas contact surface of the paint layer, and this frictional energy is used as energy for paint movement. Since unbalanced movement energy is applied to the trap pipe, it is possible to rapidly generate a swirling motion in the paint layer within the trap pipe, and in this state, in order to send it into the pipe and move it, the starting end of the pipe to be treated is This has the effect of reliably applying the paint to the entire inner surface, including the inner surface on the upper side.

In addition, a compressor and a trap pipe are all that is needed, and conventional two-component airless atomizers and pressure feed hoses are not required at all, so it is possible to significantly reduce the work process, number of workers, and time, thereby increasing work efficiency. It has the effect of being able to significantly raise the height and also greatly reducing the lining cost. Furthermore, since the main ingredient and curing agent of the epoxy resin paint are mixed in fixed quantities, troubles caused by mixing errors can be completely prevented, and after lining is completed, only the trap pipe needs to be cleaned with thinner, so the time it takes for the paint to harden is reduced. It has the advantage of being shortened to 30 minutes or more.

In addition, in the present invention, pressurized gas is sent into the trap pipe at the required pressure to obtain a predetermined wind speed in the pipe to be treated, so the paint may have a viscosity of 10,000 CP or more, and the experimental results do not According to the company, the inner surface coating of the pipe was made 10 mm thick using a highly viscous paint of 25,000 CP, which has an unprecedented effect in increasing the durability of the pipe.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of a conventional pipe lining method, Fig. 2 is a schematic diagram of an embodiment of the present invention, Fig. 3 is a vector diagram of frictional energy generated from wind speed in the pipe, and Fig. 4 is a FIG. 5 is a longitudinal cross-sectional view of the pipe to be treated, and FIG. 6 is a cross-sectional view taken along the Y--Y line in FIG. 5. 1... Compressor, 2... Pipe to be treated, 5...
Trap pipe, P...paint, P'...pressurized gas contact surface.

Claims (1)

[Claims] 1. A trap pipe is airtightly connected to the starting end of the pipe to be treated, an epoxy resin paint mixed with a base agent and a curing agent is filled and sealed in the trap pipe, and a predetermined pressurized gas is fed into the paint in the trap pipe. A method for lining the inner surface of a pipe, which is characterized by generating swirling flow, causing the swirling flow to move through the pipe, and coating the entire inner surface of the pipe.