JPS6231794A - Method of corrosionproof construction of pipe joint - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a corrosion prevention method suitable for joints of various pipes, particularly joints of pipes buried in the ground or submerged in water.

(Prior art) Even if the outer periphery of a metal pipe is coated with synthetic resin such as PVC or PE, the anticorrosion effect will not be exhibited unless the joints of the pipes are properly waterproofed. , Apply a waterproof primer such as grease to the pipe joint, then apply a putty-like solid anticorrosion to fill in any unevenness, wrap anticorrosion tape over it, and finally wrap the external tape or paint the external surface. The exterior surface was finished to prevent corrosion at the joints.

(Problems to be solved by the invention) However, the conventional method described above requires many steps and is inefficient, and in cases where the work is buried underground, sloppy work or omissions can be fatal to corrosion protection. I often ended up giving .

In view of these points, the present invention aims to provide a corrosion protection method that shortens working time, simplifies workability, has high working efficiency, and is capable of complete corrosion protection.

(Means for Solving the Problem) The present invention achieves the above object by attaching a cover body to a pipe joint part, which can cover the joint part including the connected pipe ends while maintaining a space, and This is a corrosion prevention method for pipe joints that seals the outer periphery of pipe joints with foamed resin by injecting a foamed resin forming agent through injection holes provided in some parts and filling the space inside the cover body with foamed resin. As the cover body, it is preferable to use a transparent body (including a translucent body in the present invention).

(Example) Next, the present invention will be explained with reference to drawings shown as an example.

FIG. 1 is a sectional view of an example of a tube joint according to the present invention, and FIG. 2 is a perspective view of the cover body shown in FIG. 1 in a separated state,
Reference numerals 1 and 2 are corrosion-resistant pipes made by coating at least the outer periphery of a metal pipe with synthetic resin, and a metal flange 3.4 is welded to the exposed end of the metal pipe by peeling off the synthetic resin at each end of the pipe. They are connected by bolting flanges 3.4. 5 is a cover body, and the tube 1. The synthetic resin No. 2 is formed in such a shape that it covers the peeled end of the pipe and the flange joint while maintaining a space 6, and a filling hole 9 and an air vent hole 10 are formed on the outer circumferential surface, and the overall structure is ! It is formed in a half-shape with W7 around it, and both ends that are attached to the outer periphery of the tube 1.2 are formed to have an inner diameter that is approximately the same as the outer diameter of the tube 1.2, and the edges are Backing 8 is attached.

First, the cover body 5 is attached to the joint of the tubes 1 and 2, and the collar 7 of the cover body 5 is fixed by screwing, etc., and then the foamed resin forming agent is injected through the filling hole 9. Then, the internal air escapes from the air vent hole 10, and the foamed resin 11 enters the space 6.
fills and seals the joint. In this way, the construction of the anti-corrosion method of the present invention is completed.

The above-mentioned foamed resin forming agent is a two-component reaction consisting of a gas-injected synthetic resin agent whose main ingredient is isocyanate filled in a cylinder and a gas-injected synthetic resin agent whose main ingredient is polyether polyol filled in another cylinder. A mold-type foamed urethane forming agent, a one-component foamed urethane forming agent containing isocyanate as a main ingredient, and any other foamed resin forming agent that can be instantaneously foamed when applied on-site may be used.

If the cover body 5 is formed transparent (including translucent),
This is convenient because the filling state of the foamed resin can be visually checked. Note that the positions and numbers of the filling holes and air vent holes may be appropriately set according to the size and external shape of the joint so that the space 6 can be sufficiently filled with the foamed resin, and the holes may be bored on site.

FIG. 3 shows an example of a different half-split cover body, and this cover body 5a has one side in the tube axis direction that is connected to the opening/closing axis.
2a, and has a configuration that can be opened and closed in half. Although not shown, it is also possible to have a vertically split shape in the direction perpendicular to the tube axis, and the fixing of the cover body is In addition to using fixing members such as screws and clamping members as described above, fitting of uneven portions provided on the cover body, sliding engagement using locking portions, etc. may also be used.

Figure 4 shows one example of a different joint between pipes.The synthetic resin covering the ends of pipes 1b and 2b is peeled off to expose the metal pipes, and the ends of each metal pipe are After forming the tapered screws 13b and 14b, the pipes 1b and 2b are connected by a nimple 15b with taper screws formed on both inner surfaces, and the joint may have any other suitable configuration, and the cover body 5b is connected to A space 6b may be formed around the outer periphery, and the foamed resin 11b may be sufficiently tightly coated.

Further, if the joint part is elbow-shaped, cheese-shaped, etc., the cover body may also be shaped into an elbow-shaped, cheese-shaped, etc. corresponding thereto.

(Effects of the Invention) As described above, according to the present invention, the joint can be formed by simply attaching the cover to the joint and injecting the foamed resin forming agent through the injection hole of the cover. - This foamed resin can be reliably filled in every detail, so a certain corrosion protection effect can be achieved with efficient work, and the foamed resin is not damaged by the presence of the cover body. There is no problem of deterioration over time.

If the cover body is transparent, work efficiency will be further improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an example of a pipe joint according to the present invention, FIG. 2 is a perspective view of the cover body shown in FIG. 1 in a separated state, and FIG. 3 is a schematic side sectional view showing another example of the cover body. FIG. 4 is a half-cut front view showing another example of the tube joint compared to FIG. 1. 1.2-pipe, 5-cover body, 6-space, 8-puffing, 9-filling hole, 10-air vent hole, 1l-=-foamed resin.

Claims (1)

[Claims] A cover body that can cover the joint part including the connected pipe ends while maintaining a space is attached to the pipe joint part, a foamed resin forming agent is injected from an injection hole provided in a part of the cover body, and the cover body is covered. A corrosion prevention method for pipe joints that seals the outer periphery of pipe joints with foamed resin by filling the space inside the body with foamed resin.