JPS5838512B2 - Deep buried external power source cathode protection electrode device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a deep-buried externally powered electrolytic corrosion protection electrode device for corrosion protection of metal buried objects such as pipelines and foundation piles.

Recently, many deep-buried electrode type external power supply devices have been installed, which have less interference with adjacent pipes and are excellent in current distribution to the physical pipes.

One of the electrode devices used for this has been proposed as shown in a schematic vertical cross-sectional view in FIG.

That is, a plurality of magnetic iron oxide anodes 2 are placed inside the protective steel pipe 1.
are mutually insulated and held by a support metal fitting consisting of an anode spacer 8 and two reinforcing bars 9.

These anodes 2 are connected to appropriate positions 4 of electric wires 3 through anode lead wires 10, and these electric wires 2 are led out from the top of the steel pipe 1 to the outside of the soil and connected to a DC power supply device (not shown). Connected to the positive side.

Further, a degassing vibro made of synthetic resin having countless holes 5 is housed inside the steel pipe 1 to prevent chlorine or oxygen gas electrolytically generated from the anode 2 from filling the steel pipe 1. There is.

Note that 7 is a backfill material made of graphite grains and coke grains filled in order to reduce the grounding resistance of the anode 2.

And, 250 to 350 such conventional electrode devices were excavated at predetermined positions in the soil! 1;' XI It is installed in a cylindrical hard hole of 00m.

However, the following two problems remain in the conventional electrode device.

The first is the conventionally used magnetic iron oxide, high silicon cast iron,
Graphite and other anodes have a common disadvantage of high wear rate and poor mechanical strength, so they are large and the anode itself and the anode lead wire are heavy. However, since the support metal takes up space, the diameter of the protective steel pipe must be increased, and as a result, the cost of polling is actually 1/3 to 1/3 of the order amount for the cathodic protection equipment. 1
/4.

Second, backfill enters and accumulates through the opening of the gas vent pipe, making it impossible to efficiently exhaust the generated gas, which increases the resistance inside the electrode device, reduces the generation of anti-corrosion current, and causes the wire sheathing to deteriorate. There was a risk that it would deteriorate and that sufficient anticorrosion effects could not be expected for a long period of time.

The present invention has been made to solve the above-mentioned conventional problems, and it greatly improves economic efficiency compared to conventional cathodic protection equipment by minimizing the cost of polling work, and also eliminates the possibility of backing up in gas venting pipes. The purpose is to provide an electrode device in which no fill material enters and accumulates, and the gist of the device is to provide a synthetic resin degassing pipe with a plurality of openings inserted into a protective steel pipe, a plurality of insoluble anodes, these pipes, and an anode. In an externally powered cathodic protection electrode device that is buried deep in the soil and has a backfill filled in the gap between the steel pipe and the steel pipe, an insoluble anode in the form of a wire, foil, or wire mesh is applied to the outer peripheral surface of the wire coating. A deep-buried type external power source electric shield characterized in that the anode is formed integrally with the electric wire, a part of the anode is electrically connected and fixed to the electric wire, and the outer peripheral surface of the pipe is wrapped with a fiber tape. It is an edible electrode device.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 2, the electrode device of the present invention is shown in a schematic longitudinal sectional view, and the same parts as the conventional electrode device shown in FIG. 1 are designated by the same numbers.

A plurality of wire mesh-like insoluble anodes 2' made of platinum-plated tantalum are formed so as to surround the coated outer surface of the wire 3, and a portion of these anodes 2' is connected to the wire by a connector 11 at an appropriate position on the wire 3. It is electrically connected and fixed to the core wire 12, and is kept watertight by the filler 13 and the synthetic resin tube 14.

Further, the outer peripheral surface of the degassing vibro made of synthetic resin and having countless holes 5 is wrapped in a half-fold and single layer with a fiber tape 15, for example, a glass cloth tape.

This tape 15 is corrosion-resistant and satisfies the conditions that particles of the backfill 7 cannot pass through it and gas can pass through it.

Then, a protective steel pipe 1 containing the above-mentioned anode-attached electric wire and gas venting pipe was excavated at a predetermined position in the soil.
It is installed in a 10m cylindrical hard hole.

Although a wire-mesh-shaped anode was used in this example, a wire-shaped insoluble anode made of platinum-plated titanium may be wound around the outer circumferential surface of the electric wire in a coil shape or arranged in a straight line along the outer circumferential surface of the electric wire. An encased foil-like insoluble anode may also be used.

In the past, the anodes were divided into insulated sections at appropriate intervals as shown in this embodiment, and in addition to being connected to electric wires, one anode could also be used as a long piece.

Further, it is more effective if the protective steel tube of the electrode device of the present invention is connected to the positive side of the DC power supply and used as an anode.

As explained above, according to the electrode device of the present invention, the poling diameter is 115 to 1/7 compared to the conventional electrode device.
Therefore, the polling construction cost can be significantly reduced to about 115 yen compared to the conventional method, and the construction period can also be shortened.

In addition, since the degassing nozzle never gets clogged, the generated gas can be quickly discharged to the outside of the soil, so a stable anti-corrosion effect can be expected over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a conventional electrode device, and FIG. 2 is a schematic vertical cross-sectional view of the electrode device of the present invention. 1... Protective steel pipe, 2.2'... Anode, 3... Electric wire,
6... Gas vent pipe, 7... Back fill, 15
...Fiber tape.

Claims (1)

[Claims] 1 A synthetic resin degassing vibro having a plurality of openings 5 inserted into a protective steel pipe 1 and a plurality of insoluble anodes 2, and a backfill 7 filled in the gap between the vibro, the anode 2, and the steel pipe 1. A button is attached to an externally powered cathodic protection electrode device deeply buried in the soil, and is integrally formed on the outer circumferential surface of the coated wire 3 of an insoluble anode wire 3 in the form of a wire, foil or wire mesh, A deep-buried external power supply cathodic protection electrode device characterized in that the = section of the anode 2' is electrically connected and fixed to the electric wire 3, and the outer peripheral surface of the vibro is wrapped with a fiber tape 15. .