JPS5894688A - Method of renewing buried pipe to novel pipe - 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 The present invention relates to a method for replacing buried old city gas pipes with new pipes.

When a city gas pipeline, etc. buried underground reaches the end of its useful life, conventionally, as shown in the shaded area in Figure 1, the entire length of the renewal extension is excavated, the old pipe is dug up, and the new pipe is replaced. Since it is intended to be replaced with a new one, it has the drawback that excavation work and backfilling work require a lot of time and expense. or,
When this renewal work is done on the road surface, it is necessary to cut off the main traffic, and there are many restrictions on the renewal.

The present invention has been proposed in view of the above points, and its gist is that a shaft is excavated at both ends of the location where the old pipe to be replaced is buried until the old pipe is exposed, and 3 No. □ Lever The old pipe is cut in the shaft, then a new pipe is connected to one end of the cut old pipe, and the old pipe is pulled out at the other end of the old pipe while simultaneously being replaced with a new pipe. .

The present invention will be described in detail below based on the drawings. First, as shown in FIG. A puller 5 is set in one of the shafts 2 and the exposed old pipes 1 are cut in the shafts 2 and 3 (Fig. 3).
.

Then, as shown in Fig. 4, in the shaft 3 on the side other than the shaft 2 where the extractor 5 is set, a new pipe 6 is attached to the tip of the old pipe l.
are connected by the joint tool 7, and the extractor 5 is operated to pull out the old pipe 1 in the direction of the arrow in FIG.

As a result, the new pipe 6 is connected to the old pipe 1, so when the old pipe 1 is pulled out, the new pipe 6 is pulled in afterwards as shown in Figure 5, and at the same time as the old pipe 1 is pulled out, the new pipe 6 is connected to the old pipe 1. Tube 6 is replaced.

Note that the old pipe 1 may be pulled out from the drawing machine 5 to the ground as it is, but in the case of the embodiment, it is cut into short pieces with a cutter inside the shaft 2.

When the replacement of the new and old pipes, i.e., the renewal, is completed as described above, the puller 5 is removed from the shaft 2, and both ends of the new pipe 6 are connected to the existing pipes 9 and 10 that were cut earlier. 2.
All work will be completed by backfilling 3 and performing other measures such as paving.

In addition, there was significant corrosion in the middle of the old pipe 1, and the extraction machine 5
There are some that cannot withstand the pulling force.

In such cases, it is necessary to not only connect the new and old pipes, but also
As shown in FIG. 6(a), a wire or rod-shaped tow rope 8 is inserted into the old pipe 1, the tip of which is connected to the new pipe 6, and the tow rope 8 is also used or this tow rope 8 is used. Pull in new pipe 6. Alternatively, the tip of the tow rope 8 may be engaged with the old pipe 1 within the joint tool 7, as shown in FIG. 6(b).

Next, the new pipe 6 may be thicker than the old pipe 1. In such a case, as shown in FIG. 7, a joint tool 7 whose external shape is tapered and thickened on the side of the new pipe 6 is used to minimize the resistance in the soil.

As described above, the present invention creates the shaft 2.3 by excavating only the both ends of the old pipe 1 that needs to be replaced, and does not excavate the middle, so it is more efficient than the conventional method of excavating the entire pipe. The cost of excavation, backfilling and paving can be greatly reduced. Particularly, the present invention is particularly effective when the update distance is long. In addition, even when updating across a road, it is convenient to be able to do the updating work without blocking traffic, and conventionally it was not possible to do the updating work at night in consideration of the traffic blockage. There used to be many, but there will no longer be a need for something like this.

Note that, of course, if a branch pipe is connected to the old pipe 1, it is necessary to remove this branch pipe in advance.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of an example of conventional new and old pipe renewal work, Figure 2-
Figure 5 is an explanatory diagram of the construction method of the present invention, Figures 6 (a) and (b) are cross-sectional views showing an example of a method for connecting new and old pipes using a joint tool and a towing cable, and Figure 7 is a diagram of a new pipe. No. -19- It is a sectional view showing an example of a joint tool when the pipe is thicker than the old pipe. ■・・・ Old pipe, 2.3... Vertical shaft, 5... Pulling machine, 6... New pipe, 7... Joint tool, 8... Towing Cable, 9.1o...Existing pipe. Patent applicant Tokyo Gas Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 5 Figure 7

Claims (1)

[Claims] 1. A shaft is excavated until the old pipe is exposed at both ends of the location where the old pipe to be replaced is buried, and the old pipe is cut within the shaft, and then the cut old pipe is removed. A method of replacing a buried pipe with a new pipe by connecting a new pipe for renewal to one end of the pipe, and pulling out the old pipe at the other end of the old pipe and replacing it with a new pipe at the same time. 2. A method for replacing a buried pipe with a new pipe according to claim 1, in which the old pipe is cut while being pulled out in a shaft on the drawing side. 3. If the old pipe is corroded in the middle or cannot withstand the pulling force, pass a tow cable through the old pipe, connect the new pipe to this tow cable, and use the tow cable together with the old pipe. A method for updating a buried pipe to a new No. -1111 pipe according to claim 1, wherein a new pipe is pulled in while pulling out an old pipe. 4. When the new pipe is thicker than the 11] pipe, the joint tool for joining the old pipe and the new pipe is a tapered joint tool in which the external shape on the new pipe side gradually becomes thicker.Claim 1
How to replace buried pipes with new pipes as described in section.