JPH0327800B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a repair branch structure used when repairing cast iron pipes, steel pipes, etc. that have branch pipes buried in existing soil.

In order to repair an existing underground pipe, as shown in Figure 1, a predetermined length of repair steel pipe 01 is rolled up and shrunk so that it overlaps slightly, without joining the joint line 02 in the pipe axis direction. The pipe is brought into the existing underground pipe 03, the rolled state is released and the diameter is enlarged, and the joint line 02 in the pipe axis direction is joined to connect the pipe to the existing underground pipe 03. A tube with a diameter smaller than the inner diameter of
Next, arrange this concentrically with the underground pipe 03,
The rear end 05 of the repair pipe 04 whose tip is placed first
Then, the underground pipe 03 and the repair pipe 01
There is a repair method for underground pipes called the pipe-in-pipe method, in which the gap 06 between the pipe and the pipe is filled with mortar.

If the existing underground pipe 03 has a branch pipe 07, as shown in Figure 2, mortar 08
In order to prevent the water from flowing into the branch pipe 07, a closing plate 09 is installed at the open end of the branch pipe 07, and then mortar 08 is applied to the gap between the buried pipe 03 and the repair pipe 04.
After that, a shaft 010 is dug to the extent that a worker can enter and work near the branch pipe 07, and from there, another branch pipe 011 is passed through the underground pipe 03. Since it was connected to the internal repair pipe 04, there were problems in that the construction work was complicated, the labor and cost increased, and the construction period became longer.

The present invention was proposed in order to solve the above-mentioned problems, and its purpose is to enable repair work on branch pipes from within the underground pipe, such as excavating a shaft or repairing another branch pipe. The aim is to eliminate complicated construction work such as joining pipes.

The gist of the present invention is that a repair pipe 3 is inserted into the inside of an underground pipe 1, a hole 12 is made in the repair pipe 3 at the position of the branch pipe 2, and a hole 12 is opened in the repair pipe 3 at the position of the branch pipe 2. A branch repair pipe 6 inserted into the interior, a water stop fitting 7 fitted between the outer periphery of the outer end of the branch repair pipe and the inner periphery of the branch branch pipe 2, and a branch at the inner end of the water stop fitting 7. It is characterized by consisting of a gasket 9 fitted watertightly between the repair pipe 6 and the branch pipe 2, and mortar 5 filled inside the gasket 9 between the underground pipe 1 and the repair pipe 3. In the present invention, by having the above structure, it is possible to repair the branch pipe part from inside the underground pipe, and therefore, it is possible to perform repair work on the branch pipe part from inside the underground pipe, and therefore, it is possible to carry out repair work on the branch pipe part from inside the underground pipe. This eliminates the need for complex construction work such as joining the branch pipes, making repair work on branch pipes simple and easy, reducing costs and construction times. It becomes possible to repair branch pipe sections.

Hereinafter, the present invention will be specifically explained with reference to an embodiment shown in FIGS. 3 to 7. In Figure 3, 1 is an existing underground pipe, 2 is a branch pipe,
3 is a repair pipe, 5 is mortar, 6 is a branch repair pipe, 7
indicates a water stop fitting, 8 indicates a stopper, and 9 indicates a gasket. As shown in FIG. 5, the branch repair pipe 6 has a smaller diameter than the branch pipe 2 and is inserted into the branch pipe 2, and has a flange portion 6b on the outer periphery of its lower end that tightly contacts the inner surface of the repair pipe 3, and a flange portion 6b in the middle thereof. It is provided with a stopper receiver 6c provided on the outer circumferential surface, and its upper end opens into the branch pipe 2 and its lower end opens into the repair pipe 3. The water stop fitting 7 has three cylinders 7a, 7 as shown in FIG.
b and 7c are stacked and welded to each other, and the innermost cylinder 7a is positioned inside the branch repair pipe 6, straddling the upper end of the branch repair pipe 6, and its lower end is connected to the inner surface of the branch repair pipe 6. The outermost cylinder 7c is fitted into the gap 10 between the branch pipe 2 and the branch repair pipe 6 from above, and its lower end abuts the upper surface of the gasket 9.

The stopper 8 has an annular shape and is placed on the stopper receiver 6c. The gasket 9 has an annular shape, and the upper surface of the stopper 8 and the outermost cylinder 7 of the water stop fitting 7.
c, and is brought into close contact with the inner surface of the branch pipe 2 and the outer surface of the branch repair pipe 6. Therefore, when repairing the branch pipe 2, first check the position of the branch pipe 2 through the small hole 11 drilled in the repair pipe 3, as shown in A of Fig. 3, a hole 12 with a diameter slightly larger than the inner diameter of the branch pipe 2 is bored. Next, as shown in B, the water stop fitting 7, gasket 9, and stopper 8 are inserted in this order into the branch pipe 2 through this hole 12.
Next, as shown in C, the branch repair pipe 6 is pushed in until the upper surface of the flange portion 6b comes into close contact with the inner surface of the repair pipe 3, and after the center of the branch repair pipe 6 is aligned with the center of the branch pipe 2, the flange portion 6b is The outer peripheral edge of the repair pipe 3 is fillet welded 13 to the inner surface of the repair pipe 3. Next, as shown in D, pull the water stop fitting 7 by hand or with a device in the direction of the arrow in the figure, place the stopper 8 on top of the stopper receiver 6c, place the gasket 9 on top of it, and place the top end of the water stop fitting 7 on top of that. The lower end of the outer cylinder 7c is brought into contact and pressed to bring the gasket 9 into close contact with the inner surface of the branch pipe 2 and the outer surface of the branch repair pipe 6. Next, as shown in E, the lower end of the innermost cylinder 7a of the water stop fitting 7 is fillet welded 14 to the inner surface of the branch repair pipe 6. Thereafter, if necessary, repair coating is performed around the fillet welds 13 and 14. Thus, underground pipe 1 and repair pipe 3
When mortar 5 is injected into the gap between the pipe and the pipe, the gasket 9 prevents the mortar 5 from leaking into the branch pipe 2.

Since all of these operations can be performed from inside the underground pipe 1, the conventional work of excavating a shaft and performing it from outside the pipe can be omitted, making the construction simple and easy. Therefore, the cost and construction period can be reduced.

In addition, if the shaft cannot be excavated or if the branch pipe 2
Even if the diameter of the branch pipe is small, it is possible to repair the branch pipe section.

In the above embodiment, the branch repair pipe 6 is provided with a stopper receiver 6c, and the stopper 8 is placed thereon, but a stopper can be attached to the branch repair pipe 6. In addition, although the water stop fitting 7 is made by stacking three cylinders 7a, 7b, and 7c and welding them together, it is also possible to manufacture the water stop fitting 7 as a single body by casting or the like.
A and 7b may be omitted, and the outermost cylinder 7c may be fixed to the upper end of the branch repair pipe 6 by fillet welding.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an outline of the pipe-in-pipe construction method, FIG. 2 is a cross-sectional view showing a conventional branch pipe repair procedure, and FIGS. 3 to 7 show an embodiment of the present invention. Figure 3 is a sectional view showing the branch structure, Figure 4 is an enlarged view of Figure 3, Figure 5 is a perspective view of the branch repair pipe, Figure 6 is a perspective view of the water stop fitting, Figure 7 is It is a figure showing a construction procedure. Stopper...8, Branch pipe...2, Repair pipe...
3. Branch repair pipe...6. Gasket...9. Water stop fitting...7.

Claims (1)

[Claims] 1 Repair pipe 3 inserted inside underground pipe 1
, a hole 12 made in the repair pipe 3 at the position of the branch pipe 2, a branch repair pipe 6 inserted into the branch pipe 2 through the hole 12, and an outer circumference of the outer end of the branch repair pipe 6 and the branch pipe. a water stop fitting 7 fitted between the inner periphery of the pipe 2;
A gasket 9 is fitted watertightly between the branch repair pipe 6 and the branch pipe 2 at the inner end of the water stop fitting 7, and a gasket 9 is filled inside the gasket 9 between the underground pipe 1 and the repair pipe 3. A repair branch structure characterized by comprising mortar 5.