KR20080052401A - Method for pipe lining - Google Patents

Abstract

A pipe lining method is provided to coat the entire pipe in the uniform film thickness by partially coating an under coating layer from the end of the pipe to a region over a second joint and then, coating the front side of the pipe. A pipe lining method for coating the inner walls of pipes(1,1-1~1-5) installed in a building with paints containing solvent-free two-liquid type epoxy resin by blowing the paint from apertures(11) of each end of the pipes by pressure of the air comprises an under coating process for partially coating an under coating layer by injecting the amount of under coating paints enough to coat a part from the end aperture of the pipe over a second joint(17) of the pipe and blowing the air from the aperture, and a lining process for coating the front side of the pipe by injecting lining paints from the end aperture of the pipe right after partially coating the pipe, and making the paint reach the other end aperture by blowing the air from the aperture.

Description

Lining method of pipes {METHOD FOR PIPE LINING}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lining method for pipes in which paint is applied to an inner circumferential surface thereof in order to renew existing pipes already installed in various buildings.

Conventionally, in order to rebuild existing piping already installed in a building, especially a water supply pipe, the inner surface of the piping is polished in advance to remove rust, and then a coating made of a solvent-free two-component epoxy resin is applied. Application of the paint is performed by setting the paint in an opening at one end of the pipe and blowing the paint into the pipe by the pressure of air to spread it.

By the way, when coating was performed by spreading the paint from one end side to the other end side of the pipe as described above, there was a problem of causing unevenness in the thickness of the coating film at one end side and the other end side. This is based on the reason that the coating film thickness at one end side to which air is blown becomes thinner than the other end side due to the wind pressure or the like.

In order to solve this, for example, as shown in Patent Literature 1, the coating of the coating material of the whole pipe (secondary coating) is applied to a short range of the pipe near one end side (air inlet side) where the coating film is easily formed thinly. ), Coating (primary coating), etc. beforehand is performed. As a result, a substantially uniform coating film can be formed over the entire pipe.

However, when the primary and secondary coatings are applied, secondary coating cannot be performed after the primary coating, until this becomes the dry touch state, and the time required for the coating is long (for example, about 2 hours). There was a problem.

In addition to the fact that the coating on one end of the air blowing side is thinned due to the wind pressure, the other end of the air is blown, the pipe diameter near the tip is small or affects the hose connected to the end. In addition, it is confirmed that the coating becomes thinner because the air flow rate is increased.

[Patent Document 1]

Japanese Patent Application Laid-Open No. 2006-263601

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and an object thereof is to provide a lining method for pipes which can perform coating of substantially uniform film thickness throughout the pipe and can shorten the time required for coating. Is in.

The invention described in claim 1 of the present invention relates to a lining method of a pipe in which a coating made of a solvent-free two-component epoxy resin is applied to an inner wall of a pipe provided in a building by blowing air pressure from an opening at each end of the pipe. An undercoating step of partially coating an undercoating layer by injecting an amount of undercoating paint exceeding a second joint of the pipe from the opening of the pipe end and blowing air from the opening, and partial coating of the pipe. And a lining step of immediately applying the lining paint from the opening of the end of the pipe to blow the air from the opening to reach the opening of the other end to perform a front coating of the pipe. It is in the lining method of the pipe. Moreover, as a typical method of the process of performing the said undercoating process and a lining process, after performing undercoating from all the edge parts of a piping, it transfers to a lining process and performs a front coating on all the piping, and the both ends which perform a lining process After the undercoating is finished, lining is performed (that is, the lining is performed every time the two ends of the undercoat are coated).

According to the invention described in claim 2, in the lining method of the pipe according to claim 1, the front coating of the pipe by the lining paint is performed before the dry touch of the undercoat layer. have.

The invention described in claim 3 is a lining method of a pipe according to claim 1 or 2, wherein the paint for lining and the paint for lining are different paints.

The invention described in claim 4 is a lining method for pipes according to claim 3, wherein the viscosity of the paint for undercoating is higher than the viscosity of the paint for lining.

The invention described in claim 5 of the present invention is the lining method of a pipe according to claim 3, wherein the air supply pressure of the undercoat paint is greater than the air pressure of the lining paint.

According to the invention as set forth in claim 1, after partial coating of the undercoating layer from the end of the pipe to the area beyond the second seam, the front coating of the pipe is performed. Therefore, coating of uniform film thickness over the entire pipe can be performed. Can be. In addition, since the front coating is performed immediately after the partial coating of the pipe, the time required for painting can be shortened.

According to the invention described in claim 2, since the front coating is performed immediately without waiting for the dry touch of the partial coating, the time required for painting can be shortened.

According to the invention as set forth in claim 3, since the undercoat paint and the lining paint are made of paints of different compositions, the material of the undercoat paint can be used as a material capable of easily applying the lining paint immediately. .

According to the invention described in claim 4, since the viscosity of the undercoat paint is higher than that of the lining paint, the undercoating paint is applied even when the undercoating paint is applied and subjected to a dry touch. A paint does not flow with this lining paint, and the thickness of the coating film of the area | region which under-coated can be maintained.

According to the invention described in claim 5, since the coating pressure of the undercoat paint is made larger than the coating pressure of the lining paint, the undercoat is applied when the undercoat is overlaid even before the undercoat paint is applied and dried. The coating material for coating does not flow with this coating material for lining, and the thickness of the coating film of the area | region which under-coated can be maintained.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail with reference to drawings.

1 is a schematic perspective view showing an example of a pipe lining according to the present invention. The piping 1 shown in the said figure simplified and showed the water supply pipe already installed in buildings, such as an apartment. As shown in the figure, the pipe 1 is configured by connecting a plurality of branch pipes 1-1, 1-2, 1-3, 1-4, 1-5 with each other, for example, this pipe ( In the case of 1), the branch pipe (1-1) is the pipe leading to the water meter, the branch pipe (1-2) is the pipe leading to the toilet, the branch pipe (1-3) is the pipe leading to the washroom, and the branch pipe (1-4) is the bathroom Piping, branch pipes (1-5) are pipes leading to the kitchen. In addition, the piping 1 shown by the solid line in the said figure has shown the state which removed the power receiving equipments (a power supply mechanism, a joint, valves, piping, etc.) of the installation which uses this water supply pipe, and shows each branch pipe (1-1-1-1-). The opening 11 at the end of 5) is usually at a position immediately after being exposed from the wall of the building. Lining is performed in the state which the power receiving apparatus was removed in this way. In addition, the part shown with the dotted line is the working pipe 20 used by connecting to the opening 11 at the time of the following lining work.

Each branch pipe (1-1 to 1-5) is generally provided with a rising portion (15) from the opening (11) via a first seam (elbow) 13, and further supports a second seam (elbow) 17. The horizontal portion 19 is provided, and is connected to each other via the third joint (tees) 21. Moreover, it goes without saying that the fourth and fifth joints may be further needed, or the third joint 21 or the like may become unnecessary in some cases.

As shown in FIG. 1, the water meter, the toilet facilities, and the like are first removed, and then the drainage and drying of the pipe 1 are performed, followed by polishing in the entire pipe 1 in order to remove rust and scale in the pipe 1. Do the work. And the lining of the piping 1 which concerns on this invention is performed. The lining method is explained below. The lining method which concerns on this invention is performed by performing a lining process after an undercoating process.

[Under coating process (1st painting)]

First, the working pipe 20 shown by the dotted line in FIG. 1 is connected to the opening 11 of each branch pipe 1-1-1-5. On the other hand, the compressor 30 and the header 31 are prepared and the compressor 30 is connected to the header 31. The header 31 has a plurality of connection ports each provided with a slew valve 33, and connects each connection port and each work pipe 20 with a hose 35. The hose 35 and the work pipe 20 are easily connected to or detached from each other by a cam lock or the like. Next, the branch pipe to be removed and undercoated by removing the hose 35 from one branch pipe (1-1 to 1-5) to be undercoated and one branch pipe (1-1 to 1-5) for drawing air. From the opening 11 (exactly the opening of the working pipe 20) of (1-1 to 1-5), the amount of the undercoat paint required to slightly exceed the second joint 17 of the branch pipe is introduced to the hose. (35) is provided, and the compressed air from the compressor (30) is blown from the opening of the working pipe (20) through the header (31) and the hose (35) to spread the undercoat paint, and the opening of the branch pipe. The undercoat is partially coated on the inner wall surface from (11) to the position beyond the 2nd joint 17 (for example, 1.5 m). In this embodiment, the coating material which consists of a non-solvent type two-component epoxy resin whose mixing viscosity is 35.0 (Pa * s) is used as a coating material for undercoat. Moreover, the air supply pressure of the air blown in from the opening 11 is 0.25 (MPa) in this embodiment.

2 is a view showing an example of the working procedure of the undercoating step. In this work procedure, the opening 11 of the branch pipes 1-1 to 1-5 is closed by first closing all the slew valves 33 of the header 31, and then the branch pipes 1-3 and the branch pipes ( The hose 35 is removed from the work pipe 20 connected to 1-1), and the second joint 17 of the paper pipe 1-3 is removed from the opening of the work pipe 20 of the paper pipe 1-3. After the amount of the undercoat paint amount exceeded, the hose 35 was installed in the work pipe 20 of the branch pipe 1-3, and then the slew valve of the header 31 corresponding to the branch pipe 1-3. (33) is opened to blow air from the opening 11 of the branch pipes 1-3 to spread the coating material for the undercoating, from the opening 11 to the position beyond the second joint 17 to the inner wall surface thereof. Partially coat the undercoat. At this time, air escapes from the opening of the working pipe 20 of the branch pipe 1-1. Delivery time is 1 minute, for example. Next, the opening 11 of the branch pipe 1-3 is closed by closing the slew valve 33 of the branch pipe 1-3, and in the same manner as described above, the opening 11 of the branch pipe 1-3 is removed from the opening 11 of the branch pipe 1-3. 2 Undercoat the partial coating on the inner wall surface to the position beyond the joint 17. At this time, air escapes from the opening of the working pipe 20 of the branch pipe 1-1. Next, the opening 11 of the branch pipes 1-4 is closed, and the undercoating layer is applied to the inner wall surface from the opening 11 of the branch pipes 1-5 to the position beyond the second joint 17 in the same manner as described above. Partial coating. At this time, air escapes from the opening of the working pipe 20 of the branch pipe 1-1. Next, the opening 11 of the branch pipe 1-5 is closed, and the undercoating layer is applied to the inner wall surface from the opening 11 of the branch pipe 1-2 to a position beyond the second joint 17 in the same manner as described above. Partial coating. At this time, air escapes from the opening of the working pipe 20 of the branch pipe 1-1. And finally, the opening 11 of the branch pipe 1-2 is closed, and the positive under which exceeds the 2nd joint 17 of the branch pipe 1-1 from the opening 11 of the branch pipe 1-1. The coating paint is introduced to install the hose 35 in the work pipe 20 of the paper pipe 1-1, and at the same time, the hose 35 connected to the paper pipe 1-3 is removed, and the paper pipe is made in the same manner as described above. The undercoat is partially coated on the inner wall surface from the opening 11 in (1-1) to the position beyond the second joint 17. At this time, air escapes from the opening of the working pipe 20 of the branch pipe 1-3. This completes the undercoating process. In the undercoating, it is difficult to visually check the delivery to the target portion of the paint. In this embodiment, the position beyond the second joint 17 based on the diameter of the pipe, the physical properties of the paint, the air supply pressure, and the air flow rate. A time sufficient for delivery (painting) of the paint up to this point is determined, and management by delivery time is performed.

[Lining process (secondary painting)]

Next, in Fig. 3, lining paint is introduced from one of the openings 11 (exactly, openings of the working pipe 20) of the branch pipes 1-1 to 1-5, and air is released from the opening 11. The coating for lining the entire pipe 1 (front coating on the wall surface of the pipe) is performed by repeating the blowing process to reach the opening (reach) 11 of the other branch pipe. In other words, the amount of lining paint to be added is slightly larger than necessary from the opening 11 to the opening 11 to reach. For example, as shown in FIG. 3, when the coating material for lining is apply | coated toward the opening 11 of the branch pipes 1-4 from the opening 11 of the branch pipes 1-3, all of the header 31 is applied. By closing the slew valve 33, the opening 11 of the branch pipes 1-1 to 1-5 is closed, and the hose 35 is removed from the work pipe 20 connected to the branch pipes 1-3. The lining paint is introduced from the opening of the work pipe 20, and the hose 35 is again installed in the work pipe 20 of the paper pipe 1-3, and from the opening 11 of the paper pipe 1-4. Remove the hose 35 and install a transparent hose 41 instead, connect it to the paint receiver 40, and then open the slew valve 33 of the header 31 corresponding to the branch pipe 1-3. Air is blown through the opening 11 of the branch pipe 1-3 to spread the lining paint into the branch pipe 1-4, and the paint is drawn from the opening 11 of the branch pipe 1-4. 1 ball by confirming that the discharge To an end. The confirmation that the lining paint has reached the opening 11 of the branch pipe 1-4 which is the arrival port is judged by the paint coming out of the transparent hose 41. Next, when the lining paint is applied from the opening 11 of the branch pipe 1-3 to the opening 11 of the branch pipe 1-5, the opening 11 of the branch pipe 1-4 is applied. Remove the hose 41 from the hose 35 and install the hose 35 to close the opening 11, while removing the hose 35 from the opening 11 of the branch pipe 1-5 and replace the hose 41 instead. To the paint receiver 40, the hose 35 is removed from the work pipe 20 of the branch pipe 1-3, and the amount exceeding the opening 11 of the branch pipe 1-5 from the opening. The lining paint is added, and the lining coating from the branch pipes 1-3 to the branch pipes 1-5 is performed by the same method as described above. The same applies to the other branches.

This lining coating is immediately performed after partial coating of the branch pipes 1-1 to 1-5 by the undercoating step. That is, it is performed before the undercoat layer is touch-dried (hardened so that it may not flow). In this embodiment, the coating material which consists of a non-solvent type two-component epoxy resin whose mixing viscosity is 23.2 (Pa * s) is used as lining paint. Moreover, the air supply pressure of the air blown in from the opening 11 is 0.15 (MPa) in this embodiment.

4 is a view showing an example of the working procedure of the lining step. In addition, the operation | work which attaches or detaches the hose 35 and the paint receiver 40 is abbreviate | omitted in the following description. As shown in the figure, in this embodiment, as described above, a lining layer is formed on the inner wall surface from the opening 11 of the branch pipes 1-3 to the opening 11 of the branch pipes 1-4. Next, a lining layer is formed on the inner wall surface from the opening 11 of the branch pipe 1-3 to the opening 11 of the branch pipe 1-5. Next, a lining layer is formed on the inner wall surface from the opening 11 of the branch pipe 1-3 to the opening 11 of the branch pipe 1-2. Lastly, a lining layer is formed on the inner wall surface from the opening 11 of the branch pipe 1-3 to the opening 11 of the branch pipe 1-1. As a result, all the pipes 1 are completely coated and the lining process is completed. After completion of the lining process, for example, hot air is forcedly dried in the pipe 1 to be forcibly dried, and the power receiving equipment on the various equipment side is restored to perform an air leak test, water quality inspection, and the like, and a series of operations are completed.

In addition, as a procedure of a lining process, it is not limited to what was shown in FIG. 4, As shown in FIG. 5, it paints from the branch pipe 1-5 to the branch pipe 1-4 first, and the branch pipe 1-4 sequentially after that. ), Branch pipes (1-3), branch pipes (1-3) to branch pipes (1-2), branch pipes (1-2) to branch pipes (1-1). The order may be sufficient. It does not matter if it is the order in which the whole pipe is painted.

By the way, in this invention, the coating material of the other composition in the non-solvent type two-component epoxy resin is used as the coating material for undercoat and the lining, and the viscosity of the undercoat paint is higher than the viscosity of the lining paint To be. In other words, it is preferable that the viscosity of the coating material for undercoat is 150% or more of the viscosity of the coating material for lining like the said embodiment. Thus, the viscosity of both paints is different in the present invention in order to be able to apply the coating material for lining even before the coating for undercoating is applied and subjected to tactile drying. That is, when both paints having the same viscosity are used, when the lining layer is to be formed immediately after the undercoating layer is formed (before the drying), the undercoating layer is spread by the air pressure for forming the lining layer, and the undercoating layer is formed. The uniformity of the coating film over the entire piping length, which is the purpose of installation, cannot be maintained. Therefore, in the present invention, the viscosity of the coating material for the undercoat is higher than the viscosity of the coating material for the lining, whereby the undercoating layer does not spread even when the lining process is performed immediately after the undercoating layer is formed (before the drying). Because of the higher viscosity, the undercoating layer is fixed at its original position (partial painting position) to achieve uniformity of the coating film over the entire length of the pipe. It is.

That is, in order to prevent the undercoat layer from spreading due to the air supply pressure at the time of coating the lining paint, the viscosity of the undercoat paint is made higher than the viscosity of the lining paint, and compared to the air pressure of the undercoat paint. The air supply pressure is made smaller. In other words, in this invention, the air supply pressure of the undercoat paint becomes larger than the air supply pressure of the lining paint. In particular, the air supply pressure of the undercoat paint is preferably 150% or more of the airflow pressure of the lining paint as in the above-described embodiment.

As mentioned above, both the coating material for undercoating and the coating material for lining consist of a non-solvent type two-component epoxy resin, and the viscosity is changed by changing the composition. Preferably, as the coating material for undercoating, those having a mixing viscosity of 7.5 to 75 (Pa · s) and a pot life time of 5 to 45 minutes (300 g, 23 ° C.) are used as the coating material for lining. (Pa * S) and the thing of 5-45 minutes (300g, 23 degreeC) of the pot life is used. Of course, you may use paint other than this condition.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, A various deformation | transformation is possible within the scope of a claim, and the technical idea described in specification and drawing. Moreover, even if it is any shape, a structure, and a material which are not directly described in a specification and drawing, it is in the range of the technical idea of this invention, as long as it has the effect and effect of this invention. For example, although the said embodiment demonstrated the case where this invention was used for the lining of the water supply pipe attached to a building, it can be applied similarly to the lining of other various piping. In the above embodiment, the paint is set in an opening at one end of the pipe, and the paint is blown into the pipe only by the pressure of air. However, in some cases, a ball shape having an outer diameter smaller than the pipe inner diameter with the paint may be used. The coating member may be applied by inserting a pressurizing member into the pipe and pushing the pressurizing member into the pipe by the pressure of air. Moreover, in the said embodiment, although the case where the lining process is performed after finishing the undercoating process of all the pipe ends is demonstrated, after lining process is performed to both ends of the branch pipe which performs a lining process, a lining process is performed to those branch pipes ( In other words, the method of lining the two ends of each of the two ends is sequentially performed on the entire pipe.

1 is a schematic perspective view showing an example of piping to be lined;

2 is a view showing an example of the working procedure of the undercoat step;

3 is a view showing a lining process;

4 is a view showing an example of the work procedure of the lining step;

5 is a view showing another example of the work procedure of the lining process.

※ Explanation of code for main part of drawing

1: Piping 1-1, 1-2, 1-3, 1-4, 1-5: Branch pipe

11: opening 13: first joint

15: rising portion 17: second joint

19: Third seam 20: Working tube

30: compressor 31: nozzle

40: paint receiver 41: hose

Claims (5)

In the lining method of the piping in which the paint which consists of a solvent-free two-component epoxy resin is blown into the inner wall of the piping installed in a building by blowing in the air pressure from the opening of each end part of a piping, An undercoating step of partially coating the undercoating layer by injecting an amount of the undercoating paint exceeding the second joint of the pipe from the opening of the pipe and blowing air from the opening; After the partial coating of the pipe, a lining process is performed in which the lining paint is immediately introduced from the opening of the pipe end and the air is blown in from the opening to reach the opening of the other end to carry out the front coating of the pipe. Lining method of the pipe, characterized in that provided. The method of claim 1, The front coating of the pipe by the lining paint is carried out before the dry touch of the undercoat layer. The method according to claim 1 or 2, The underlining paint and the lining paint are different paints. The method of claim 3, wherein The viscosity of the paint for undercoating is higher than the viscosity of the paint for lining, The lining method of the piping characterized by the above-mentioned. The method of claim 3, wherein The air supply pressure of the undercoat paint is greater than the air pressure of the lining paint.

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