JP2001182863A - Disposal method of buried pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To waste a buried pipe in a buried condition without exerting wrong effect on homebuilding and the like. SOLUTION: A carbon rod 11 is disposed in a buried pipe 10, electrolyte 12 and an insulating base material 13 are filled therein, voltage is applied between the carbon rod 11 and the buried pipe 10, and thereby, electric corrosion of the buried pipe 10 is treated, and furthermore, mechanical strength is lost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a buried pipe such as a buried supply pipe branched from a gas pipe conduit (main pipe or branch pipe) buried under a road and drawn into a demanded residential land. The present invention also relates to a disposal method of a buried pipe for disposing the buried pipe in a buried state.

[0002]

2. Description of the Related Art FIG. 2 is an explanatory view showing a piping system of a supply pipe extending from a main pipe buried under a road to a residential land of a demand destination. In the figure, reference numeral 1 denotes a conduit called a main pipe or a branch pipe laid below a road surface a at a required burial depth, and reference numeral 2 denotes a branch branched from the conduit 1 and located in a residential land b of a demand destination. The supply pipe and the inner pipe that are retracted. Here, if the house in the residential land is removed and the residential land is vacant,
The above-mentioned supply pipe is cut near the boundary between road and residential land,
It is necessary to remove the unused supply pipe 2a.

Conventionally, the operation of removing the unused supply pipe 2a is performed by excavating and removing the entire area of the buried unused supply pipe 2a, or as shown in FIG.
Excavation points A and B are excavated on both sides of a, and a pipe extracting device 3 is set in the excavating point A on one side. Drawer part 2a '
Was cut and removed, and the drawing and cutting and removing were repeated to remove the unused supply pipe 2a.

[0004]

If the supply pipe 2a is left in a buried state, it adversely affects other works such as water pipe work, which is inconvenient. However, when removing supply pipes,
According to the above-mentioned conventional method of excavating and removing the entire supply pipe, there is a problem that digging and backfilling require a large amount of cost and time. Further, according to the method using the above-described pipe drawing device, the excavation and backfilling portion is only the excavated portions A and B, and the labor required for excavation and backfilling is reduced.
There is a problem that the working time is prolonged because the drawing and cutting of the pipe must be repeated many times, and there is a problem that the cost is increased as a whole because a pipe drawing device requiring a large amount of power is used. Further, according to the latter method using a pipe drawing device, there is a problem that a cavity is formed in a drawing trace of a buried pipe after work, and this cavity affects a base of a house.

The present invention has been proposed in order to cope with such a situation, and fundamentally reverses the concept that buried pipes left under a road must be removed. It is an object of the present invention to dispose of the buried pipe so as not to affect other works and to eliminate the above-mentioned problem in removing the buried pipe.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, a method of disposing of a buried pipe is performed by removing a metal buried pipe buried underground. A rod-shaped electrode is provided, an insulating substrate and an electrolytic solution are filled, and a voltage is applied between the rod-shaped electrode and the buried pipe to subject the buried pipe to electrolytic corrosion treatment.

The present invention according to claim 2 is characterized in that a corrosion promoting liquid is injected into a metal buried pipe buried underground, and the buried pipe is subjected to corrosion treatment.

According to a third aspect of the present invention, for a metal buried pipe buried underground, liquid nitrogen is injected into the buried pipe to embrittle the buried pipe. I do.

According to the above construction, the buried pipe is rapidly corroded or embrittled, and loses its structural strength. Therefore, when the excavation work is performed in another construction or the like, the buried pipe has no strength, and the buried pipe has no influence. Moreover, although the buried pipe does not keep its original shape, it is interposed in the ground, so that there is no inconvenience that a cavity is formed underground. This eliminates the necessity of removing unnecessary buried pipes, so that the cost and time required for the removal work can be saved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing a disposal method of a buried pipe according to one embodiment of the present invention. Reference numeral 10 denotes a buried pipe made of an iron pipe such as the supply pipe described above. A carbon rod 11, which is a rod-shaped electrode, is disposed inside the buried pipe. The arrangement of the carbon rod 11 is performed by cutting the carbon rod 11 into short pieces and connecting them with a flexible conductive material to make the whole flexible, forming a dug portion as shown in FIG. Or may be arranged in the pipe in advance when the pipe is buried. The buried pipe 1 on which the carbon rod 11 is disposed
In contrast, around a carbon rod 11, a mixture of an electrolyte solution 12 such as salt water and an insulating base material 13 such as gravel and sand flows and fills. At this time, it is important to fill the insulating base material so that the carbon rod 11 does not contact the inner surface of the buried pipe 10.

After the disposition of the carbon rod 11 and the filling of the electrolyte 12 and the insulating substrate 13 are completed, the carbon rod 11 is connected to the cathode and the buried tube 10 is connected to the anode, and a voltage is applied between the two. . Depending of this, in the buried pipe 10 is an iron ^{pipe, Fe → Fe + 2 + 2e} - ionization reaction proceeds made, it can corrode the buried pipe 10 in the iron oxide. The above voltage is applied to the buried pipe 1
Continue until the 0 erodes and loses its mechanical strength. Then, when this is completed, the carbon rod 11 is removed.

According to this, the corroded buried pipe and the insulating base material remain underground, but the corroded buried pipe loses its mechanical strength, so that there is no need for any foundation work such as excavation. There is no influence, and since the inside of the buried pipe is buried with an insulating base material, there is no inconvenience such as land subsidence.

In the above embodiment, an iron pipe has been described as an example.
It is needless to say that the present invention can be applied to other metal pipes capable of performing the electrolytic corrosion treatment. Further, when the inner surface of the buried pipe is plated, the corrosion of the buried pipe can be more effectively advanced by performing the step of removing the plating as a pretreatment.

As a second embodiment, not shown,
A corrosion-promoting solution such as a weakly acidic aqueous solution is injected into the buried pipe together with the gravel, and the buried pipe is forcibly corroded. As a result, as described above, the corroded buried pipe has no mechanical strength, so it has no effect on foundation work such as excavation, and does not form a cavity in the ground. There is no inconvenience such as settlement.

Further, as a third embodiment, although not shown, liquid nitrogen gas is sealed in the buried pipe from one end opening of the buried pipe. Then, the temperature of the buried pipe rapidly decreases and becomes brittle, and loses the strength as a structure. As a result, as described above, the corroded buried pipe has no mechanical strength, so it has no effect on foundation work such as excavation, and does not form a cavity in the ground. There is no inconvenience such as settlement.

[0016]

Since the present invention is configured as described above,
It is possible to dispose of the buried pipe so that it will not affect other works while buried. This eliminates the need to remove unnecessary buried pipes, and saves cost and time required for removal work.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a piping system of a supply pipe from a gas pipe conduit to an inner pipe in a residential land of a demand destination.

FIG. 3 is an explanatory view showing a conventional example.

[Explanation of symbols]

 Reference Signs List 10 buried pipe 11 carbon rod 12 electrolyte 13 insulating base material

Claims (3)

[Claims] A metal buried pipe buried underground is provided with a rod-shaped electrode therein, filled with an insulating base material and an electrolyte, and a voltage is applied between the rod-shaped electrode and the buried pipe. A method of disposing of a buried pipe, wherein the method is applied and the buried pipe is subjected to electrolytic corrosion treatment. 2. A disposal method for a buried pipe, wherein a corrosion promoting liquid is injected into a metal buried pipe buried underground, and the buried pipe is corroded. 3. A disposal method for a buried pipe, wherein liquid nitrogen is injected into the buried pipe into a metal buried pipe buried underground to embrittle the buried pipe.