JPH0134780B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for painting a pipe with mortar lining, and more particularly, to a method for painting a mortar lining on a pipe by centrifugally spraying mortar onto the inner surface of the pipe to form a lining coating layer.

When reclaiming existing buried pipes such as water pipes and gas pipes, the inside of the pipes is lined with mortar. Such a mortar lining layer has the risk of cracking and sometimes partially peeling off due to slight vibrations received from heavy vehicles or the like during long-term use, so it is desired to apply reinforcement means. Recently, methods using glass fibers (alkali-resistant), such as those found in reinforced plastics, have attracted attention as a method of reinforcing the mortar lining layer. A method of spraying short glass fibers and short glass fibers individually and simultaneously has been tried, but this method not only tends to cause operational problems such as clogging of the short fibers, but also Since the reinforcement was made of fibers, the reinforcing effect was still unsatisfactory. This problem of reinforcing effect can be solved by using reinforcing materials such as long glass fibers, nets, or wire mesh, but mortar lining in pipe reclamation is work within a narrow space called the inside of the pipe. Since this usually spans a long distance of around 100 m, it is very difficult to apply such reinforcing materials to the mortar lining layer. Furthermore, the lining layer formed by centrifugal spraying often entrains air and contains air pockets, and such air pockets reduce the strength of the lining layer.

The present invention provides a pipe lining coating method that can easily form a mortar lining coating layer that is reinforced with reinforcing materials such as glass fiber nets or wire mesh, and whose inner layer is compacted to prevent air pockets. The present invention has been made for the purpose of providing, namely, a step of centrifugally spraying mortar on the inner surface of a pipe to form an inner layer of a lining coating layer, and before curing the inner layer, adding glass fiber to the inner layer. , a flexible tube that is non-adhesive to the mortar, which holds a cylindrical net made of an adhesive reinforcing material such as a metal wire on the outer peripheral surface of the mortar, is pressurized into the tube. A step of compressing and deaerating the inner layer by pressing it into a lining shape while being reversely inserted with a fluid, and simultaneously lining the inner layer with the cylindrical net, supplying heated pressurized fluid into the tube that is crimped into a lining shape. A step of heating the inner layer of the lining coating layer through the tube to promote curing while maintaining the inner lining crimped state, and adhering and holding the cylindrical net to the inner layer. After the inner layer of the lining coating layer has hardened, attaching the inner layer to the mortar Step of removing only the flexible tube that is non-adhesive to mortar from inside the pipe while keeping the adhesive cylindrical net adhered to the inner layer; A mortar lining coating method for a pipe, which comprises the steps of centrifugally spraying the coating material to form an outer layer of the lining coating layer, and bonding and integrating the outer layer with the inner layer through the mesh of a cylindrical net. .

In the mortar lining coating method of the present invention, since the mortar lining coating layer is reinforced with reinforcing materials such as glass fibers and wire mesh, mechanical reinforcement can be further enhanced compared to conventional reinforcement using short glass fibers, and the lining The inner layer of the coating layer is compressed and degassed during tube crimping, and the reinforcement from this side is strengthened, so as a whole, the risk of cracks in the lining coating layer due to micro vibrations and peeling off can be eliminated. and its durability can be significantly improved. Furthermore, when forming the lining coating layer, we used a tube that was inserted upside down into the pipe to bring it in and attach it to the inner layer of the lining coating layer. It can be easily and accurately inserted into a predetermined position within the lining coating layer without damaging the inner layer at all, and has the characteristic that such a reinforced mortar lining coating layer can be easily and efficiently formed. .

In the lining coating method of the present invention, mortar is used as the coating material. This mortar is applied to the inner surface of the pipe by applying centrifugal spraying means commonly employed in this field of technology to form the inner or outer layer of the lining coating.

The tube that is crimped onto the inner surface of the lining coating layer should be made of a material that is flexible, expands when fluid is press-fitted, and contracts when the press-fit is released, and does not exhibit adhesion to mortar. things are used. Such tubes may be advantageously made of, for example, nylon, polyurethane, polypropylene, polyethylene, or polyvinyl chloride. The tube usually has a diameter that is approximately equal to or slightly larger than the inner layer.

As a cylindrical net used as a reinforcing material for the mortar lining coating, it is compatible with the mortar, adheres to it, and contributes to strengthening the mortar, and can also follow the reverse insertion of the tube when placed over the outer circumferential surface of the tube. It is not particularly limited as long as it is made of such a material. Examples of such reinforcing materials include cylindrical nets made of glass fibers and cylindrical nets woven from ultrafine steel wires.

The means for crimping the tube to the inner surface of the lining coating inside the pipe is as follows:
It is possible to adopt a method of inserting the tube inverted into the pipe using fluid pressure and sequentially crimping the tube onto the inner surface of the pipe from one end toward the other end. By adopting such measures, the lining of the reinforcing material can be carried out without any damage to the inner layer.

The cylindrical net (reinforcing material) is inserted into the tube prior to the tube lining crimping process, and is configured to be located on the outer peripheral surface side of the tube when it is reversed.

Then, when the tube holding the cylindrical net in this way is crimped to the inner layer of the pipe as a lining,
The cylindrical net comes into close contact with the inner layer surface in the pre-hardened state, and when heated and pressurized fluid is applied into the tube while maintaining this close contact state to promote hardening of the inner layer, the cylindrical net is attached to the hardened inner layer surface of the mortar. is adhered and retained. In adhering this cylindrical net, the mortar constituting the inner layer acts as an adhesive and firmly adheres the cylindrical net. On the other hand, tubes are not compatible with mortar and do not substantially adhere to the inner layer surface even after the mortar hardens, leaving them in a free state. Therefore, after the inner layer has hardened, the tube can be easily peeled off and removed from the inner layer surface by releasing the supply of heated and pressurized fluid into the tube.

The outer layer of the lining coating layer is formed by centrifugal spraying on the inner surface of the inner layer after the tube is removed. This formed outer layer is adhesively integrated with the inner layer through the mesh of the cylindrical net by its own adhesive property, and a mortar lining coating layer reinforced by the cylindrical net is obtained.

In the present invention, the mortar lining coating layer only needs to be a combination of such inner and outer layers. For example, in addition to the inner and outer layers, the inner layer or the outer layer may be laminated singly or repeatedly. In this case, there is a cylinder between each layer. A shaped net is interposed by applying the above-mentioned means.

In the present invention, air is generally used as the pressurized fluid used for crimping the tube lining.

Further, heated air, steam, etc. are used as the heated and pressurized fluid used to accelerate hardening of the inner layer. Of course, other pressurized fluids or heated pressurized fluids may be used. The latter heated pressurized fluid may also be used as the former heated fluid. The pressure of the pressurized fluid and the heated pressurized fluid should be large enough to make the cylindrical net in the folded state follow the expansion or inversion of the tube, and is usually within the range of 0.5 to 5 Kg/cm ² as appropriate. selectively determined.

An embodiment of the construction method of the present invention will be described below based on the accompanying drawings.

FIG. 1 shows how an inner layer 2 of mortar lining is formed on the inner surface of a pipe 1. When forming the inner layer 2, as in the conventional mortar lining method, a centrifugal spraying machine 3 is towed inside the pipe 1 by operating a rope 4, and during the towing, the spraying machine 3 is The compressed mortar is sprayed in a centrifugal direction from the rotary head 3a to form an inner layer 2 of mortar lining on the inner surface of the pipe 1. In the figure, 6 is a cone-shaped presser iron provided in the centrifugal spray machine 3.

FIG. 2 shows the process of crimping the lining of the tube 7 to the inner layer 2 of the mortar lining shown in FIG. As shown in FIG. 3, the tube 7 has a cylindrical net 8 as a reinforcing material on its inner peripheral surface. This can be easily obtained by placing a cylindrical net 8 over the outer peripheral surface of the net 7 and inverting it using known means. Tube 7 is the third
As shown in the figure, it is folded vertically with the cylindrical net 8 held inside, and in this flat state is wound onto a roll 9 (see FIG. 2).

As is clear from FIG. 2, when the inner lining of the tube 7 is crimped, the tube 7, which is first wound up on the roll 9, and the cylindrical net 8 therein are attached to the starting end of the pipe 1 at their respective starting ends. band 1
0, and then pressurized fluid, for example pressurized air, is supplied into the pipe 1 from a supply pipe 12 provided in the airtight casing 11 containing the roll 9, via the casing and the conduit 13.
The pressurized air supplied into the pipe 1 acts on the outer surface of the tube 7 as a force that forces it into the pipe 1 while inverting it, and thus the tube 7 and the cylindrical net 8 inside thereof are inverted and pushed into the pipe 1. They are inserted into the pipe 1 in order from the starting end, and are finally lined and crimped over the entire length of the pipe 1. It should be noted that such lining crimping of the tube 7 is performed on the inner layer 2.
This is done quickly before it hardens.

FIG. 5 shows the state of the curing and hardening process of the mortar lining inner layer 2. In this process, both ends of the tube 7 and the cylindrical net 8, which are lined and crimped to the inner layer 2, are fixed to the corresponding ends of the pipe 1, and blind caps 14a, 14b was applied,
One cap 14a is provided with a supply pipe 16 for heated pressurized fluid, such as steam or heated air, with an on-off valve 15. And in this state pipe 1
A heated pressurized fluid is supplied within the chamber. The supply of this heated and pressurized fluid heats the mortar inner layer 2, promoting its curing and hardening, and by the hardening of the mortar inner layer 2, a cylindrical net 8 that is compatible with the mortar is formed on the inner surface of the mortar using the mortar as an adhesive. is glued. On the other hand, the tube 7 is made of thermoplastic resin and has poor compatibility with mortar, so the tube 7 is substantially free from the mortar inner layer 2. Therefore, by releasing the supply of heated and pressurized fluid, the tube 7 is able to drain the mortar inner layer 2 as shown in FIG.
It can be easily peeled off and removed from the surface. In Figure 6, 1
7 is a roll for winding up the tube 7. After removing tube 7 from inside pipe 1 in this way,
As shown in FIG. 7, the outer layer 18 of the mortar lining is formed by applying the centrifugal spraying method shown in FIG. A mortar lining layer is obtained.

[Brief explanation of drawings]

The drawings show a state in which the method of the present invention is carried out. Fig. 1 is a longitudinal cross-sectional side view showing the formation of the inner layer of the mortar lining, and Fig. 2 is a longitudinal cross-section showing the inner lining of the tube with reinforcing material bonded to the inner layer of the mortar lining. 3 is a perspective view of the main part of the tube with reinforcing material shown in FIG. 2, FIG. 4 is a perspective view of the main part of the tube with reinforcing material shown in FIG.
The figure is a longitudinal cross-sectional view showing the curing and hardening status of the inner layer of the mortar lining, Figure 6 is a vertical cross-sectional view showing the condition during peeling and removal of the tube, and Figure 7 is a vertical cross-sectional view showing the formation status of the outer layer of the mortar lining. . In the figure, 1 is a pipe, 2 is an inner layer of mortar lining, 3 is a centrifugal spray machine, 4 is a rope for pulling operation, 5 is a supply pipe, 6 is a presser iron, 7 is a tube, and 8 is a cylindrical net. , 9 is a roll, 10 is a band, 11 is an airtight casing, 12 is a supply pipe, 13
1 is a conduit, 14 and 14b are blank caps, 15 is a valve, 16 is a supply pipe, 17 is a roll, and 18 is an outer layer of mortar lining.

Claims (1)

[Claims] 1. A step of centrifugally spraying mortar on the inner surface of the pipe to form an inner layer of the lining coating layer. Before the inner layer hardens, the inner layer is coated with mortar such as glass fiber or metal wire. A flexible tube, which is non-adhesive to the mortar and which holds a linear net made of an adhesive reinforcing material on the inner circumferential side, is inverted and inserted by pressurized fluid supplied into the tube. A step of compressing and deaerating the inner layer by crimping it into a lining shape, and lining the inner layer with the cylindrical net at the same time; supplying a heated pressurized fluid into the tube crimped in the lining shape to maintain the lining crimped state; a step of heating the inner layer of the lining coating layer through the tube to accelerate curing, and adhering and holding the cylindrical net to the inner layer; A step of removing only the flexible tube that is non-adhesive to mortar from the inner surface of the pipe while it remains adhered to the inner layer, and centrifugally spraying mortar onto the surface of the inner layer which adheres and holds the cylindrical net. A method for mortar lining a pipe, comprising the steps of forming an outer layer of the lining coating layer and adhering and integrating the outer layer with the inner layer through the mesh of a cylindrical net.