JPS6156032B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for lining the inner surface or sealing leakage points using a lining material or a sealing material for various existing conduits, such as for city gas, natural gas, oil, water, etc. More specifically, the present invention relates to a method of applying a fluid lining material or sealing material to the inner surface of an existing conduit located at an installation site and curing the applied lining material or sealing material.

If a cylindrical lining material is used to treat the inner surface of an existing conduit, it may be difficult or impossible to introduce the lining material into the conduit, or it may be difficult to treat the inner surface with the lining material adhered to the entire circumference of the conduit. However, such disadvantages can be avoided by adopting a method of attaching and hardening a fluid lining material or sealing material to the inner surface of the conduit. Therefore, conventionally, thermosetting, photocurable, or room temperature curing resins have been used as such fluid lining materials or sealing materials. However, when thermosetting resin is used and the resin is cured by supplying hot air into the pipe, the cure is faster on the hot air supply side, resulting in uneven curing, and the curing speed is averaged. When attaching resin to a conduit while heating it, the longer the length of the process, the more large-scale equipment is required, and especially in the case of buried conduits, large-scale excavation is required. It involved construction work and was inferior in terms of economy and workability. In addition, when thermosetting or photocurable resin is cured using a heating device or a lighting device that passes through the pipe at the same time as or after applying it to the pipe, it is particularly important to This poses technical problems because bends and inner diameter changes tend to occur. Furthermore, when a room temperature curable resin is used, it takes a long time to cure, resulting in poor work efficiency. Furthermore, even if any of the above resins is used, if underground water or the like flows into the pipe, the lining material or sealing material may be washed away or peeled off by the inflow water before it hardens.
There is a drawback that the coating treatment cannot be performed on areas that really require coating treatment, or the coating treatment may be insufficient.

The purpose of the present invention is to eliminate the above-mentioned drawbacks all at once.The method uses a moisture-curing resin as a lining material or sealing material to be supplied into an existing conduit, and before applying the resin, removing moisture in the existing conduit with a gas that does not contain
When curing the resin, a gas or water containing moisture is supplied into the existing conduit, and its effects are as follows.

In other words, moisture-curing resins do not cure or have a slow curing speed in the absence of moisture or in the presence of a small amount of moisture, and harden rapidly in the presence of a large amount of moisture. After replacing the gas with a gas that does not contain moisture or does not contain much moisture, such as air or nitrogen, introduce a moisture-curing resin into the conduit and attach the resin to the conduit. It is possible to harden the lining material and sealing material by an extremely easy means such as introducing water into the pipe, and without the need for large-scale equipment. However, since the lining material and sealing material are rapidly hardened by the inflowing water, there is less risk of treatment defects due to washing away or peeling as described above, and the overall coating is extremely uniform, making it possible to economically perform the coating treatment. I can do things.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

As shown in Fig. 1, an existing conduit 1 with vertical or horizontal bends is closed at both ends with gate valves 2a and 2b, which are originally provided or installed as necessary, and between the valves 2a and 2b. At the step, a part of the conduit 1 is cut or removed to open the end, and a device 3 for pressurized supply of gas such as nitrogen gas that does not contain moisture is connected to the end of the conduit 1, and an exhaust blower 4 is connected to the conduit 1. 1 is replaced with an atmosphere such as nitrogen gas, moisture in the conduit 1 is removed with a gas that does not contain moisture, and then, as shown in FIG. Object 6 for supplying the inside and discharging it
is inserted into the conduit 1, and this object 6 is fed under pressure by the pressurized supply device 3, and the excess resin A is collected by the object 6 into the container 7, and the inner wall surface of the conduit in an atmosphere of nitrogen gas etc. Then, as shown in FIG. 3, the inside of the conduit 1 is replaced with an air atmosphere using a supply device 8 for a gas containing moisture such as air, and the moisture-curable resin A is applied to the moisture-curable resin A. The resin A is rapidly cured in a state where the curing speed is averaged, and a uniform coating of the resin A is applied over the entire inner wall surface of the existing conduit 1.

In addition, various methods can be used to attach the moisture-curable resin to the inside of the existing conduit, such as spraying the resin in an atmosphere that does not contain moisture, or filling the conduit with the resin.

Furthermore, various types of moisture-curable resins can be used, such as one-component silicone resins and cyanoacrylate resins.

[Brief explanation of the drawing]

The drawings show an embodiment of the method for treating the inner surface of an existing conduit according to the present invention, and FIGS. 1 to 3 are explanatory diagrams of the treatment steps.

Claims (1)

[Claims] 1 A method of applying a fluid lining material or sealing material to the inner surface of an existing conduit 1 located at an installation site and curing the applied lining material or sealing material, wherein the lining material or sealing material is moisture-curable. Use resin A, and before applying the resin A, remove the moisture in the existing conduit 1 with a moisture-free gas, and apply the resin A.
A method for treating the inner surface of an existing conduit, in which a gas or water containing moisture is supplied into the existing conduit 1 during curing.