JPH0565681A - External power unit for preventing corrosion and its construction method - Google Patents

Abstract

PURPOSE:To construct an external power unit which can be constructed with improved workability, capable of avoiding the cutting of its lead wire and with the entire structure miniaturized and simplified by utilizing the periphery of a synthetic-resin vent pipe to hold an electrode. CONSTITUTION:An electrode 4 is set in an embedding pit 1, the electrode is used as an anode and an object to be prevented from corrosion as a cathode, and the corrosion of the object due to the underground stray current is prevented by the external power unit. In this power unit, a conductive film 3 extending in the longitudinal direction is formed on a synthetic-resin vent pipe 2, an electrode member 4 is mounted on the pipe 2 at regular intervals and electrically connected to the film 3, the pipe 2 is introduced into the embedding pit 1, and the object is electrically connected to the electrode member 4 through the film 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a corrosion-preventing external power supply device for preventing electric corrosion of underground buried objects such as gas pipes, and a method of constructing the same.

[0002]

2. Description of the Related Art As an external power supply device for this type of corrosion protection,
A structure of a deep buried type external power supply system shown in FIGS. 7 and 8 is known. That is, in the external power supply device, a cylindrical bottomed conductive protection tube (for example, a steel tube) 102 is inserted into a pre-drilled underground burial hole 101, and an internal protection provided with a centerizer 103 therein. Pipe (eg steel pipe) 1
04, the electrode member 106 such as a platinum electrode in the form of foil is introduced through the lead wire 105, and
A synthetic resin pipe (for example, a vinyl chloride pipe) 107 for degassing is inserted in the center, and a conductive filling (for example, a backfill such as Loresco (trade name)) 108 is provided inside the protective pipes 102 and 104. And small gravel 109 is filled in the gap between the protection pipe 102 and the underground burial hole 101. The conducting wire 105 led out to the outside through the manhole 110 is connected to a gas pipe or the like buried in a relatively shallow underground, and a current is passed through this as a negative electrode to prevent galvanic corrosion due to a stray current. .. It should be noted that the inner protection tube 104 is located above the outer protection tube 1 above.
Synthetic resin protection tube 104A via joint 100 with 02
It is connected to the.

[0003]

However, in the above-mentioned conventional example, the following construction method is adopted because the electrodes are buried at a depth of about 100 m to 150 m underground. That is, since groundwater seeps into the underground burial hole, a considerable buoyancy acts on the protective tube 102 inserted therein, and therefore a weight 111 of about 1.5 ton is usually attached to the bottom of the protective tube 102. It is necessary to increase the construction cost. Further, since the electrode 106 is suspended via the conductive wire 105, a load is applied to the conductive wire 105 and its connecting / covering portion 112, and there is a risk of disconnection or the like when the conductive filling material 108 is filled. Therefore, for each electrode, measures such as connecting conductors in parallel have been made, but the work for this is complicated, and there is essentially no countermeasure for avoiding disconnection. Further, the external power supply device has a drawback in that it is structurally complicated and takes a long time to construct.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and has a structure in which the outer peripheral surface of a gas venting synthetic resin tube is used to hold an electrode and avoid the risk of cutting a conductor. SUMMARY OF THE INVENTION It is an object of the present invention to provide an anticorrosion external power supply device and a construction method thereof, which can reduce the size and simplification of the structure as a whole and improve workability in construction.

[0005]

Therefore, according to the present invention,
Place an electrode in the underground burial hole, use this electrode as the anode,
Further, in the external power supply device for corrosion protection, which uses the corrosion-resistant material as a cathode to prevent corrosion of the corrosion-resistant material by underground stray current, the conductive film extending in the longitudinal direction is provided on the outer periphery of the synthetic resin pipe for degassing, and the conductive coating is used. In a state of being electrically coupled to, the electrode members are attached to the synthetic resin pipe at predetermined intervals, and the synthetic resin pipe is introduced into the underground burial hole,
The corrosion-resistant object is electrically connected to the electrode member through the conductive film.

In this case, for example, the synthetic resin pipe is divided into a plurality in the longitudinal direction and connected to each other through a pipe joint, and the conductive film is electrically connected at the pipe joint portion. A covering tube made of synthetic resin is attached to the outside of the synthetic resin tube except at least a part of the electrode member.

Further, according to the present invention, an external power supply device for anticorrosion is provided in which an electrode is arranged in an underground burial hole, the electrode is used as an anode, and the anticorrosion object is used as a cathode for anticorrosion of the anticorrosion object by an underground stray current. In the construction method, the synthetic resin pipe for degassing, which has a conductive coating extending in the longitudinal direction on the outer periphery, is inserted into the underground burial hole, together with a synthetic resin covering pipe surrounding the synthetic resin pipe. At the connection point between the resin pipe and the next synthetic resin pipe connected to it via a pipe joint, the electrode member is fitted onto the synthetic resin pipe so as to be continuous with the covering pipe, and the electrode member is continuous with this electrode member. As described above, by fitting the next covering tube to the corresponding synthetic resin tube, the conductive structure is sequentially constructed in the longitudinal direction of the synthetic resin tube.

Further, according to the present invention, an external power supply device for corrosion protection is provided in which an electrode is arranged in an underground burial hole, the electrode is used as an anode, and the corrosion-preventing material is used as a cathode to prevent corrosion of the corrosion-resistant material by underground stray current. In the construction method of, in the underground burial hole, insert a conductive protective tube, in the conductive protective tube, in the process of inserting a synthetic resin tube provided with a conductive coating extending in the longitudinal direction on the outer periphery, By fitting the electrode member to the synthetic resin pipe at the connection point between the synthetic resin pipe and the next synthetic resin pipe connected to the synthetic resin pipe through the pipe joint, the conductive structure is sequentially formed in the longitudinal direction of the synthetic resin pipe. After the construction, a conductive filling material is filled between the electrode member and the conductive protection tube.

[0009]

Therefore, in the structure of the present invention, the electrode is mechanically and structurally held by the synthetic resin pipe for gas release and / or the covering pipe without imposing a load on the conductor wire, and the conductor wire is also in the form of a film. Since it is mounted on the synthetic resin pipe for degassing, it is possible to completely avoid the risk of disconnection when filling the conductive filler. Further, in the above configuration, even if water is put into the degassing synthetic resin pipe, there is substantially no electrical trouble, so if necessary, instead of the weight in the buoyancy countermeasure in the underground burial hole, You will be able to use water like. This is very advantageous in construction. Further, the structure is simplified and the size can be reduced as compared with the conventional one.

Further, as described above, in the construction method of the present invention, the number of working steps is reduced as compared with the conventional construction method, and the working time is shortened and the work is easy.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.
This will be specifically described. 1 to 3, reference numeral 1 is an underground burial hole, and an external power supply device inserted therein has a conductive coating 3 extending in the longitudinal direction on the outer periphery of a synthetic resin pipe 2 for degassing, Electrode members 4 are fitted to the synthetic resin pipe 2 at a predetermined interval while being electrically coupled to the conductive film 3, and the synthetic resin pipe 2 is introduced into the underground burial hole 1, The anticorrosion object (not shown) is electrically connected to the electrode member 4 through the upper end of the conductive film 3. In this case, the synthetic resin pipe 2
Are, for example, divided into a plurality in the longitudinal direction and are connected to each other via a pipe joint 5. In order to electrically connect the conductive film 3 to the pipe joint 5, for example, the pipe joint 5 may be made of a conductor or a conductive film may be formed on the outer periphery of the pipe joint 5, and further, conductive bonding may be performed. Agent, conductive adhesive parts,
Adjacent conductive films 3 may be electrically connected to each other. Further, in the above external power supply device, a synthetic resin coating pipe 6 is attached to the outside of the synthetic resin pipe 2 except at least a part of the electrode member 4. The cladding tube 6 is
The outer diameter of the electrode member 4 is substantially the same as that of the electrode member 4, and the electrode member 4 and the synthetic resin pipe 2 are fitted together with the electrode member 4 in series through a spacer 7 having the same shape. To be done. Further, the covering pipe 6 and the electrode member 4 are liquid-tightly connected by a pipe joint 8. In addition,
In the figure, reference numeral 9 is a bottom center riser, and reference numeral 1
Reference numeral 0 denotes a bottom end cap provided thereon, which receives the lower ends of the synthetic resin pipe 2 and the covering pipe 6.

In the above embodiment, the pipe joint 5 is independent of the synthetic resin pipe 2, and the synthetic resin pipes 2 are connected to each other by an adhesive agent or a screw structure. However, it may be formed integrally with one synthetic resin pipe 2 and connected to the other synthetic resin pipe 2 by the same means as above. In addition, the electrode member 4 is shown in FIG.
As shown in Fig. 4, for example, the synthetic resin support 4A has a structure in which an annular electrode plate 4B made of copper or platinum is held, but as shown in Fig. 4, it is formed on the synthetic resin ring 4A. The strip-shaped electrode plates 4B may be fitted in the slit groups. Further, in order to protect the surface of the electrode plate 4B, a conductive protective layer may be provided on the outer periphery thereof. Further, for the synthetic resin pipe 2 and the covering pipe 6 in this embodiment, for example, vinyl chloride pipes may be used. The gas vent hole 2A of the synthetic resin pipe 2 is formed so as to penetrate the electrode member 4 in this embodiment.

In constructing such an external power supply device in the underground burial hole 1, first, in the underground burial hole 1, a synthetic resin pipe 2 for venting, which has the conductive film 3 on the outer periphery thereof, is attached. Along with the surrounding synthetic resin coating pipe 6, in the process of insertion, at the connection point between the synthetic resin pipe 2 and the next synthetic resin pipe 2 connected to the synthetic resin pipe 2 via the pipe joint, the above-mentioned spacer 7 is used. The electrode member 4 is fitted on the synthetic resin pipe 2 so as to be continuous with the covering pipe 6. And in this example,
The joint portion of the covering pipe 6 including the spacer 7 and the electrode member 4 is covered and connected by the pipe joint 8. Means such as an adhesive, a joining part, and a screwing structure may be adopted for this connection. Also, so as to be continuous with this electrode member 4,
The next coated pipe 6 is fitted onto the corresponding synthetic resin pipe 2 and the pipe joint 8 is used for coating and connection. In this way, the conductive structure is sequentially constructed in the longitudinal direction of the synthetic resin tube 2.

Then, small gravel 16 is filled in the gap between the coating pipe 6 and the underground burial hole 1. Further, as a measure against buoyancy applied to the external power supply device, it is preferable that groundwater can enter the synthetic resin pipe 2. Furthermore, if necessary, a sealant for waterproofing may be loaded in the gap between the synthetic resin pipe 2 and the covering pipe 6, or a conductive filler such as Loresco (trade name) may be backfilled. You may fill as. And finally, the top cap 11
A lead wire 12 that is inserted from the conductive coating 3 and is led to the outside through a manhole 13 provided at the top of the underground burial hole 1. For example, a buried object such as a gas pipe buried relatively shallowly. (Not shown). Thereby, the electrode member 4 is used as an anode and the buried object is used as a cathode, and a current is caused to flow therethrough to prevent electrolytic corrosion of the buried object due to an underground stray current.

In the embodiment shown in FIGS. 5 and 6, a conductive protection tube 14 is attached to the outside of the external power supply device, and a conductive filling is provided between the protection tube 14 and the covering tube 6 and the electrode member 4. The configuration in which the object 15 is filled is shown. In this case, for the protection pipe 14, for example, a steel pipe may be used, and if necessary, a weight may be attached as in the conventional case.

The procedure for constructing the external power supply device having such a configuration is as follows. That is, the conductive protection tube 14 is inserted into the underground burial hole 1, and inside the conductive protection tube 14,
In the process of inserting the synthetic resin pipe 2 having the conductive coating 3 extending in the longitudinal direction on the outer periphery, at the connection point between the synthetic resin pipe 2 and the next synthetic resin pipe 2 connected to this through the pipe joint 5, By fitting the electrode member 4 on the synthetic resin tube 2,
A conductive structure is sequentially constructed in the longitudinal direction of the synthetic resin tube 2, and after the construction, a conductive filler 15 is filled between the coating tube 6 and the electrode member 4 and the conductive protection tube 14.

In each of the above embodiments, the conductive film 3
Is attached to the outer circumference of the synthetic resin pipe 2 in an annular shape, but it may be divided into a plurality of pieces in the circumferential direction to form a strip shape extending in the longitudinal direction. Further, in addition to the thin film, the plate may be attached by means such as adhesion. In such a configuration,
At the joint with the electrode member 4, some consideration must be given to the liquid-tight seal.

Therefore, in the present invention, since the conductive film 3 is attached to the synthetic resin tube 2 and the electrode member 4 is supported by the synthetic resin tube 2 and / or the covering tube 6, a load is applied to the conductor. Unlike the conventional one, there is no risk of disconnection, the structure is simplified, the radial dimension can be reduced, and the handling at the time of construction is easy, and the construction period can be shortened. Further, as in the first embodiment, when the steel pipe is not used, the work such as welding of the steel pipe is not required during the burying process.

[0019]

As described above in detail, the present invention has a synthetic resin pipe for degassing provided with a conductive coating, and the electrode member is supported by the synthetic resin pipe (and / or the covering pipe).
Since it employs a configuration that is performed by, the basic effects such as avoiding disconnection, as well as the downsizing of the device,
Many benefits such as improved workability and improved device reliability can be obtained.

[Brief description of drawings]

FIG. 1 is a partially longitudinal front view showing an embodiment of the present invention.

FIG. 2 is a partially enlarged vertical side view of the above embodiment.

3 is a cross-sectional view taken along the line ab of FIG.

FIG. 4 is a cross-sectional plan view of essential parts showing another embodiment of the present invention.

FIG. 5 is a partially longitudinal side view showing another embodiment of the present invention.

FIG. 6 is a cross-sectional plan view of essential parts taken along lines c to d showing the above embodiment.

FIG. 7 is a partially longitudinal side view showing a conventional example.

FIG. 8 is a cross-sectional plan view taken along line e to f showing the conventional example.

[Explanation of symbols]

 1 Underground burial hole 2 Synthetic resin pipe 2A Gas vent hole 3 Conductive film 4 Electrode member 5 Pipe joint 6 Cover pipe 7 Spacer 8 Pipe joint

Claims (7)

[Claims] 1. An external power supply device for corrosion protection, wherein an electrode is arranged in an underground burial hole, the electrode is used as an anode, and the corrosion-preventing material is used as a cathode to prevent corrosion of the corrosion-resistant material by underground stray current. A conductive film extending in the longitudinal direction is provided on the outer periphery of the synthetic resin pipe for use in the synthetic resin pipe, and electrode members are attached to the synthetic resin pipe at predetermined intervals in a state of being electrically coupled to the conductive film. An external power supply device for corrosion protection, characterized in that a pipe is introduced into the underground burial hole to electrically connect the corrosion-resistant object to the electrode member through the conductive film. 2. The synthetic resin pipe is divided into a plurality of pieces in the longitudinal direction and connected to each other through a pipe joint, and the conductive film is electrically connected at a portion of the pipe joint,
The corrosion-prevention external power supply device according to claim 1, wherein a synthetic resin coating tube is attached to the outside of the synthetic resin tube except at least a part of the electrode member. 3. The external power supply device for corrosion protection according to claim 2, wherein the coating pipe and the electrode member are liquid-tightly connected via a pipe joint. 4. The external power supply device for corrosion protection according to claim 1, wherein at least an outer side of the electrode plate is surrounded by a conductive protection tube electrically connected to the electrode plate. 5. The anticorrosion external power supply device according to claim 1, wherein the electrode member is composed of an annular electrode plate or a group of electrode plates arranged in an annular shape. 6. A construction for constructing an external power supply device for corrosion protection, wherein an electrode is arranged in an underground burial hole, the electrode is used as an anode, and the corrosion-preventing substance is used as a cathode to prevent corrosion of the corrosion-resistant substance by underground stray current. In the method, in the underground burial hole, in the process of inserting a synthetic resin pipe for degassing, which is provided with a conductive film extending in the longitudinal direction on the outer periphery, together with a synthetic resin covering pipe surrounding the synthetic resin pipe, At the connection point with the next synthetic resin pipe connected via a pipe joint, so as to be continuous with the coating pipe, the electrode member is fitted to the synthetic resin pipe, so as to be continuous with this electrode member, A method for constructing an external power supply device for corrosion protection, characterized in that a conductive structure is sequentially built in the longitudinal direction of the synthetic resin pipe by fitting the following covering pipe to the corresponding synthetic resin pipe. .. 7. A construction for constructing an external power supply device for corrosion prevention, wherein an electrode is arranged in an underground burial hole, the electrode is used as an anode, and the corrosion-preventing material is used as a cathode to prevent corrosion of the corrosion-resistant material by underground stray current. In the method, in the underground burial hole, a conductive protective pipe is inserted, and in the process of inserting a synthetic resin pipe having a conductive coating extending in the longitudinal direction on the outer periphery into the conductive protective pipe, At the connection point with the next synthetic resin pipe connected to this through a pipe joint, by fitting the electrode member to the synthetic resin pipe, sequentially, to build a conductive structure in the longitudinal direction of the synthetic resin pipe, After the construction, a method for constructing an external power supply device for corrosion protection, characterized by filling a conductive filler between the electrode member and the conductive protection tube.