JPS6123033B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a pair of spray guns that separately spray out a two-component sealant that react with each other and solidify are moved together in a pipe while blowing out the sealant, and The present invention relates to a method of coating the inner surface of the pipe with a reaction solidified film of a sealant.

Conventionally, two types of sealant were supplied into the mixing rotor from a pair of spray guns, and the sealant mixed inside the rotor was sprayed onto the inner surface of the pipe through small holes in the roller as the rotor rotated. For example, Japanese Patent Application Publication No. 1973-
(See Publication No. 100171).

However, due to the reaction of the sealant as it is mixed inside the rotor, the sealant becomes viscous and the small holes in the rotor become clogged with the sealant, resulting in poor discharge of the sealant.
There was a large risk of unexpected defects occurring in the inner coating of the piping, and there were drawbacks to the reliability of the inner coating.

An object of the present invention is to reliably coat the inner surface of piping with a good quality while completely avoiding the adverse effects caused by the reaction of the two-component sealant.

The characteristic means of the present invention is to directly supply the sealant to the inner surface of the piping from a pair of spray guns that separately spray a two-component sealant that reacts with each other and solidifies, so that the sealants are mixed with each other on the piping. The purpose is to mix on the inner surface, and its effects are as follows.

In other words, since the sealant is separately blown out from a pair of spray guns and is directly supplied to the inner surface of the pipe, the sealant has no chance to solidify at all before it mixes and reacts on the inner surface of the pipe. There is no possibility that a failure in supplying the sealant to the inner surface of the pipe due to reaction solidification of the sealant will occur.

As a result, it was possible to ensure the formation of a uniform and thick film through reaction solidification of the two-component sealant, and it became possible to coat the inner surface of piping with high reliability.

Next, an example will be shown with reference to FIGS. 1 and 2.

When a leak occurs in a relatively large-diameter gas pipe buried underground, a sealant blowing movable trolley 2 is inserted into the gas pipe 1 from a pit P of the leaked gas pipe 1.
The movable cart 2 has wheels 3 on its periphery, and a pair of spray guns 4, 4' are fixed to a portion corresponding to the axis of the gas pipe 1. Some of the wheels 3...
The bracket 3A is pivotably supported and is intermediately biased by springs 3B, 3B. This is to follow the unevenness on the inner surface of the tube 1.
5 and 5' are sealant tanks provided near the pit P, and both tanks 5 and 5' separately store two-component sealants S and S', which solidify together by mixing and reacting. The compressors 6, 6' simultaneously and evenly blow out both sealants S, S' from the spray guns 4, 4' through the pipes 7, 7' within a range of 360°, respectively.
This blowing is performed as the carriage 2 moves at a constant speed from the pit P on one end side to the pit P on the other end side.

Both sealants S and S' are applied to the inner wall surface of the glass tube 1.
They adhere uniformly and thinly in the circumferential direction and solidify in a short time by reacting with each other, and the gas pipe 1
A ring-shaped solidified sealant film is formed over the entire length of the pipe, thereby completing the leak repair.

Incidentally, when the pipe diameter is very large, it is also possible to mount the tanks 5, 5' and compressors 6, 6' on the self-propelled truck 2 to shorten the pipes 7, 7'.
Additionally, both spray guns 4, 4' may be configured to rotate around their axes as the trolley 2 moves, or both spray guns 4, 4' may be constructed in a double tube type and arranged concentrically. Alternatively, both sealants S and S' may be premixed during spraying.

In the above example, both sealants S and S' were sprayed out simultaneously or almost simultaneously by separate spray guns 4 and 4', but in the present invention, in addition to this, both sealants S and S' are sprayed out simultaneously or almost simultaneously. A method of pre-mixing immediately before blowing out and blowing it out is also included in the gist.

Further, this construction method may be applied to repairing leaks in water pipes, or may be applied to coating pipes with no leaks for preventive maintenance.

The two-component sealants S and S' include two-component sealants that cure at room temperature, such as urethane-based, epoxy-based, silicone-based sealants, and polysulfide.

[Brief explanation of the drawing]

The drawings show an embodiment of the piping inner surface coating method according to the present invention, with FIG. 1 being a schematic sectional view and FIG. 2 being an enlarged sectional view of the main part. 1...Piping, S, S'...Two-component sealant.

Claims (1)

[Claims] 1 Two-component sealant s that solidifies by reacting with each other,
A pair of spray guns 4, 4' that spray s' separately
While blowing out the sealants s and s', pipe 1
This is a construction method in which the inner surface of the pipe 1 is coated with a reaction solidified film of the sealants s and s', and the seal is applied to the inner surface of the pipe 1 from both spray guns 4 and 4'. A piping inner surface coating method in which sealants s and s' are directly supplied and mixed on the inner surface of the pipe 1.