JPS6123034B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for lining the inner surface or sealing leakage points of various existing conduits, such as those for city gas, natural gas, petroleum, and water, using a 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 throughout the tube, and the curing speed is averaged. When applying 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 with a heating device or a lighting device that is passed through the pipe at the same time as or after it is applied to the pipe, it is difficult to pass the resin through the pipe, especially in existing pipes. It is associated with technical problems because bends and internal diameter changes tend to exist. Furthermore, when a room temperature curable resin is used, it takes a long time to cure, resulting in poor work efficiency. The present invention aims to eliminate the above-mentioned drawbacks at once, and its method is characterized by using an anaerobic curable resin as a lining material or sealing material to be supplied into the existing conduit. In other words, anaerobic hardening resins do not harden or have a slow hardening speed in the presence of oxygen gas, and harden rapidly when oxygen gas is reduced or eliminated. After that, the resin is attached to the conduit,
Afterwards, instead of air, a gas such as nitrogen gas that does not contain or contains only a small amount of oxygen gas can be sealed into the pipe, which is an extremely easy method, and without the need for large-scale equipment, lining material or sealing material can be used. In this case, since the adhering resin is rapidly cured from the surface, the coating film is less likely to sag, and an extremely homogeneous coating process can be economically achieved as a whole. 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 this point, a part of the conduit 1 is cut or removed to open the end, and an air pressurization supply device 3 and an exhaust device 4 are connected to the end to remove the fluid such as city gas present in the conduit 1. is replaced with air, then the second
As shown in the figure, a liquid anaerobic curable resin A from a tank 5 is supplied into a conduit 1, and an object 6 for discharging it is inserted into the conduit 1, and this object 6 is The excess resin A is fed under pressure by the pressure supply device 3, and the excess resin A is collected into the container 7 by the object 6, and the anaerobic curable resin A is adhered to the inner wall surface of the conduit in an air atmosphere, and then as shown in FIG. Then, the internal atmosphere of the conduit 1 is replaced with an atmosphere such as nitrogen using a gas supplied from a device 8 that supplies a gas such as nitrogen that does not contain oxygen, thereby equalizing the curing speed of the anaerobic curable resin A. The resin A is rapidly cured in a state where the resin A is uniformly coated over the entire inner wall surface of the conduit 1. In addition, various methods can be used to attach the anaerobic curable resin A to the inside of the existing conduit, such as spraying it in a nitrogen atmosphere or filling the conduit. Anaerobic curable resin A has at least one acrylic acid group in a part of its molecular structure. Or methacrylic acid group A compound with quinones, oximes, amines, copper salts, etc.). Further, if necessary, fillers and anti-sag agents may be added to adjust the viscosity and thixotropy required for sealing and lining. A typical known anaerobic curable resin A is shown below. (1) Polyether type However, R: -H, _-CH3 , _-C2H5 , _{-CH2OH ,} R′: −H, −Cl, −CH ₃ , −C ₂ H ₅ , R″: −H, OH,

[Formula] m: 1-8 n: 2-20 p: 0 or 1 Example. Tetraethylene glycol dimethacrylate. However, R': -H, -Cl, -CH ₃ , -C ₂ H ₅ n: 1 to 20 (1) Ester type (A) Methacrylic acid ester or acrylic acid ester of polyhydric alcohol. Typical examples include (a) trimethylolpropane trimethacrylate. (b) Butanediol 1,4-dimethacrylate. (c) 2,2,4-trimethyl-1,3-pentanediol dimethacrylate. (B) Polyester acrylate. However, R ₁ : -H, -Cl, -CH ₃ , -C ₂ H ₅ , R ₂ : -CH ₂ -CH ₂ -,

[Formula] −CH ₂ −CH ₂ −CH ₂ , R ₃ : −(CH ₂ −)m− (m = integer from 0 to 8) or,

【formula】 【formula】

【formula】

【formula】

[Formula] (C) Epoxy acrylate. (D) Others

[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. 1... Existing conduit, A... Anaerobic curing resin.

Claims (1)

[Claims] 1. A method for treating the inner surface of an existing conduit, characterized by using anaerobic curable resin A as a lining material or sealing material supplied into the existing conduit 1.