JPH0440596B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of running a line through a main pipe buried or hidden by a structure in a city gas pipeline using a pressure-feed type traction device.

[Prior art]

Conventionally, both sides of the main pipe were excavated and opened, and the traction tool connected to the wire was fed from one opening to the other, or only one side of the main pipe was opened. A towing tool was forced into the opening formed in the main pipe from the above-ground part of the branch pipe that was dug out and opened and connected to the other side (I cannot provide references).

[Problem that the invention seeks to solve]

However, in any of the conventional methods, a lot of work time is required to dig out and open the main pipe, a large amount of expense is required for the excavation work and the disposal of the excavated earth, and in addition, the city gas supply must be interrupted. First, there was room for improvement in terms of workability, construction costs, and gas supply.

An object of the present invention is to enable wiring to a buried or hidden main pipe by extremely rational means, without requiring any digging or opening in the main pipe, and moreover, while continuing the city gas supply. The point is to make it so.

[Means to solve the problem]

The characteristic means of the present invention is to insert a traction tool connected to the line from the above-ground part of the upstream side of the two branch pipes connected to the main pipe, and from the downstream side of the branch pipes to the upstream side. While supplying pressurized city gas into the branch pipe, the pulling tool is force-fed from the upstream branch pipe to the main pipe and then to the downstream branch pipe in this order, and its effects are as follows.

[Effect]

In other words, the towing tool inserted from the above-ground part of the upstream branch pipe is sent to the main pipe by city gas pumped from the downstream branch pipe, and within the main pipe, it is directed to the downstream branch pipe and other branch pipes. The flowing city gas is sent to the connection point of the downstream branch pipe,
At the connection point, as city gas is supplied from the downstream branch pipe to the upstream branch pipe, the city gas flowing from the main pipe into the downstream branch pipe is fed into the downstream branch pipe, and is sent to the downstream branch pipe. City gas is sucked into the pipe and transported to the above ground area. Then, the wire is passed from the above-ground part of the upstream branch pipe to the above-ground part of the downstream branch pipe, through the upstream branch pipe, the main pipe, and the downstream branch pipe, and then from the downstream branch pipe to the above-ground part of the downstream branch pipe. Remove the equipment that supplies city gas under pressure to the upstream branch pipe, connect an appropriate device to one end of the line, pull the other end of the line, and insert the device from the branch pipe into the main pipe. The main pipe can be cleaned, lined with a lining material, internally inspected, and other appropriate treatments can be carried out by the introduced device and by moving the device within the main pipe through a wire.

〔Effect of the invention〕

The effect is that the above-ground section of the branch pipe can be used effectively to run wires to the main pipe, and there is no need to excavate the main pipe or form openings, making the construction easier, faster, and less costly. Now I can do it.

In addition, construction work can be carried out while the city gas supply from the main pipe to other branch pipes is interrupted, and overall, it is advantageous in terms of workability, economy, and gas supply, as it is possible to conduct the work through the main pipe that is buried or hidden. I am now able to take action.

〔Example〕

Next, examples will be shown.

As shown in Fig. 1, before carrying out appropriate measures such as cleaning, applying lining material, internal inspection, etc. to a part 1a of the underground city gas supply main pipe 1, When passing the wire to insert the device into the main pipe 1 and the branch pipes 2 and 3, openings are made in the above-ground parts 2a and 3a of the branch pipes 2 and 3 connected to the upstream and downstream sides of the target part 1a. form. That is, for example, an opening is formed by removing a customer gas meter and a meter cock from the manufacturer's standpipes serving as the branch pipes 2 and 3.

Next, as shown in FIG. 2, a suitable pressure-feeding towing device 4, such as a parachute or a windsock type, is inserted into the above-ground portion 2a of the upstream branch pipe 2, with a wire 5 connected thereto. At the same time, a pipe 7 with a blower 6 for supplying pressurized city gas from the downstream branch pipe 3 to the upstream branch pipe 2 is connected.

Next, while supplying pressurized city gas into the upstream branch pipe 2 by the blower 6, the traction tool 4 is force-fed to the upstream branch pipe 2, the main pipe 1, and the downstream branch pipe 3 in this order,
As shown in FIG. 8, the wire 5 is passed through both the upstream and downstream branch pipes 2, 3 and the main pipe 1 over the above ground portions 2a, 3a of the upstream and downstream branch pipes 2, 3.

Note that the amount of air blown and the discharge pressure by the blower 6 are
At least 1m/Sec or more, preferably 2m/Sec.
Also, branch pipe 2,
3, if the flow velocity is set to be equal to or higher than that of the main pipe 1, preferably at least twice the flow velocity of the main pipe 1, the pulling tool 4 can be smoothly and reliably fed from the main pipe 1 to the downstream branch pipe 3. The air volume and discharge pressure of the blower 6 are appropriately determined according to the diameters of the main pipe 1 and the downstream branch pipe 3, the flow velocity in the main pipe 1, and other conditions.

In addition, after completing the wiring, connect the pipe 7 to the branch pipes 2 and 3.
Necessary measures are taken for the main pipe 1 and branch pipes 2 and 3, such as by removing the main pipe 1 and the branch pipes 2 and 3 from the main pipe 1 and introducing appropriate devices into the main pipe 1 from the above-ground portion 2a or 3a of the branch pipe 2 or 3 by pulling with the wire 6.

Moreover, after the processing is completed, the device is pulled out through the line 5, both branch pipes 2 and 3 are restored and connected, and city gas supply to these branch pipes 2 and 3 is resumed.

[Another example]

Next, another embodiment will be described.

The traction tool 4 and the wire passage 5 can be appropriately selected in terms of material, shape, etc.
In order to insert and take out the pipes into and out of the branch pipes 2 and 3, an appropriate jig may be connected to the branch pipes 2 and 3 and used.

Various types of blowing equipment can be used to supply pressurized city gas from the downstream branch pipe 3 to the upstream branch pipe 2.

The main pipe 1 may be hidden in a structure, in which case the externally exposed parts of the branch pipes 2 and 3 are referred to as above-ground parts 2a and 3a.

[Brief explanation of drawings]

1 to 3 are conceptual diagrams illustrating the procedure of the method of the present invention. 1... Main pipe, 2... Upstream branch pipe, 2a... Above ground portion of upstream branch pipe, 3... Downstream branch pipe, 3
a... Above ground part of the downstream branch pipe, 4... Towing tool,
5... Line.

Claims (1)

[Claims] 1 Insert the traction tool 4 connected to the line 5 from the above-ground part 2a of the upstream branch pipe 2 of the two branch pipes 2 and 3 connected to the main pipe 1, and While supplying pressurized city gas from the upstream branch pipe 2 into the upstream branch pipe 2, the pulling tool 4 is moved from the upstream branch pipe 2 to the main pipe 1 and the downstream branch pipe 3.
A method for running city gas pipes under pressure in the following order: