JP2022056755A - Current/potential measuring device and electrode - Google Patents

Abstract

To provide a permanent type current/potential measuring device capable of improving workability and convenience for grasping a corrosion-resistant state of a corrosion-resistant object and the degree of consumption of a sacrificial anode, and an electrode.SOLUTION: A current/potential measuring device for grasping a corrosion-resistant state of a corrosion-resistant object subjected to corrosion resistance by a sacrificial anode includes: an electrode part including a probe electrode arranged in corrosive environment approximately same as that of the corrosion-resistant object and electrically connected to the corrosion-resistant object, and a reference electrode electrically insulated from the probe electrode and connected to the probe electrode; and a measurement part for measuring a current flowing between the sacrificial anode and the probe electrode and measuring the potential of the corrosion-resistant object by the reference electrode.SELECTED DRAWING: Figure 3

Description

The present invention relates to a permanent type current / potential measuring device and electrodes for grasping the anticorrosion state of an electrocorrosion-proof metal member and the life of the food-prevention-preventing material.

In order to prevent corrosion of steel structures installed in water or soil, electric corrosion protection using a sacrificial anode or the like is generally performed. For the sacrificial anode, metals such as aluminum, zinc, and magnesium, which have a higher electrochemical ionization tendency than steel materials, and alloys thereof are used. When the sacrificial anode is attached to the structure, an anticorrosion current flows from the sacrificial anode to the structure and the sacrificial anode itself corrodes, thereby preventing the structure from corroding. The sacrificial anode needs to be renewed regularly due to its tendency to wear out over time. In order to grasp the anticorrosion state of the anticorrosion object and the degree of wear of the sacrificial anode, the potential of the anticorrosion object and the current generated from the sacrificial anode are measured.

The anticorrosion state of the anticorrosion object by the sacrificial anode in the soil is determined, for example, by installing a reference electrode that gives a reference point of the potential in the soil and measuring the potential of the anticorrosion object with the collation electrode. For example, the negative terminal of the measuring instrument is connected to the reference electrode, and the positive terminal of the measuring instrument is connected to the anticorrosion object.

In the potential measurement of the anticorrosion state in the soil, the electrical resistance of the electrolyte in the soil affects the measured value. When the potential of the anticorrosion object is measured with a reference electrode, the measured potential includes an IR drop (mainly the product of the anticorrosion current and the electrical resistance of the electrolyte). In order to reduce the measurement error due to IR drop, an electrode called a probe made of the same material as the structure is used (see, for example, Patent Document 1). According to the technique described in Patent Document 1, a probe, a reference electrode, and a measuring unit electrically connected to an anticorrosion object in the protected soil are provided.

Japanese Unexamined Patent Publication No. 10-185800

Multiple steel pipe piles are used for piers that support floating structures such as piers. Steel pipe piles are protected by sacrificial anodes. At the pier, since a plurality of steel pipe piles are provided in a deep place on the land side, it is difficult to grasp the anticorrosion state. Therefore, the steel pipe piles along the front surface of the pier on the sea side are the measurement targets for grasping the anticorrosion state, and the actual situation is that the anticorrosion state of other steel pipe piles is not completely grasped.

In addition, wiring of the reference electrode and the probe involves complicated work. It is necessary to bury a reference electrode or the like in the soil in order to grasp the anticorrosion state in the soil of the steel pipe pile, and it is necessary to excavate the installation site in advance at the time of regular replacement and maintenance. If the method described in Patent Document 1 is applied to a steel pipe pile such as a pier, it may be difficult to install or replace a reference electrode or a probe, and it may be difficult to grasp the corrosion-proof state of the steel pipe pile.

The present invention has been made in view of the above problems, and an object of the present invention is to improve the workability and convenience of a current / potential measuring device and an electrode for grasping the anticorrosion state of an anticorrosion object and the degree of wear of the sacrificial anode. And.

In order to achieve the above object, the present invention is a current / potential measuring device for grasping the anticorrosion state of the anticorrosion object protected by the sacrificial electrode and the degree of wear of the sacrificial electrode, and is abbreviated as the anticorrosion object. An electrode portion having a probe electrode arranged in the same corrosive environment and electrically connected to the anticorrosion object, a matching electrode electrically insulated from the probe electrode and connected to the probe electrode, and an electrode portion. It is characterized by including a measuring unit for measuring the current flowing between the sacrificial anode and the probe electrode and measuring the potential of the probe electrode with the collation electrode.

According to the present invention, since the probe electrode and the reference electrode are integrally formed in the electrode portion of the current / potential measuring device, the electrode portion can be easily installed in a corrosive environment substantially the same as the anticorrosion object for a long period of time. It is possible to facilitate the measurement of current and potential over the range.

The probe electrode of the present invention is formed in a rod shape with substantially the same material as the anticorrosion object, and has an insulating portion covered with an insulating material on the surface side and an exposed portion with the material exposed. May be good.

According to the present invention, since the probe electrode is formed of a material substantially the same as that of the rod-shaped anticorrosion object in the electrode portion, the apparatus configuration can be simplified.

The exposed portion of the present invention may be formed so as to have a predetermined area.

According to the present invention, since the exposed portion of the probe electrode is formed in a predetermined area, the anticorrosion current density can be calculated based on the current flowing into the probe electrode.

In the present invention, the probe electrode and the reference electrode are integrally formed in a rod shape in the electrode portion, the exposed portion is formed on one end side of the probe electrode, and the reference electrode is electrically insulated. May be connected.

According to the present invention, since the probe electrode and the reference electrode are integrally formed in a rod shape in the electrode portion, it is possible to easily install the electrode portion in a corrosive environment substantially the same as the corrosion protection target.

The electrode portion of the present invention may be connected to the reference electrode to provide an intrusive member, and the reference electrode and the exposed portion may be embedded in the soil.

According to the present invention, since the reference electrode is provided with the intrusive member, the electrode portion can be easily embedded in the soil.

The reference electrode and the exposed portion of the present invention may be installed in water or in soil.

According to the present invention, the reference electrode and the probe electrode can be easily installed not only in water but also in soil.

The present invention may include the electrode portion embedded in soil and another electrode portion installed in water.

According to the present invention, the electrode portion can be easily installed in water and soil.

The measuring unit of the present invention may determine the anticorrosion state of the anticorrosion object based on the measurement result of the electrode unit.

According to the present invention, it is possible to determine the anticorrosion state of the anticorrosion object by using the measurement result using the electrode portion.

In the present invention, an external power supply type anode may be connected instead of the sacrificial anode.

According to the present invention, the current / potential measuring device can be applied to grasp the anticorrosion state of the anticorrosion object electrically protected by the external power supply method and the current energized from the anode (insoluble type).

The present invention is an electrode for grasping the anticorrosion state of the anticorrosion object protected by the sacrificial anode and the degree of wear of the sacrificial anode, and is arranged in substantially the same corrosive environment as the sacrificial anode. It is an electrode including a probe electrode electrically connected to the probe electrode and a collation electrode electrically insulated from the probe electrode and connected to the probe electrode.

According to the present invention, since the probe electrode and the reference electrode are integrally formed in the electrode portion for grasping the corrosion protection state of the corrosion protection target and the degree of wear of the sacrificial anode, the corrosion environment is substantially the same as that of the corrosion protection target. It is possible to facilitate the installation of the electrode portion on the surface and facilitate the measurement of current and potential.

According to the present invention, it is possible to improve the workability and convenience of the current / potential measuring device and the electrode for grasping the anticorrosion state of the anticorrosion object and the degree of wear of the sacrificial anode.

It is a figure which shows the structure of the electric corrosion protection to the corrosion protection object which has been performed conventionally. It is a figure which shows an example of the anticorrosion state determination criteria. It is sectional drawing which shows the structure of the current / potential measuring apparatus. It is a block diagram which shows the structure of the measuring part.

Hereinafter, embodiments of the current / potential measuring device of the present invention will be described with reference to the drawings. The current / potential measuring device is a permanent type device for grasping and determining the anticorrosion state of the anticorrosion object electrically protected by the sacrificial anode and the degree of wear of the sacrificial anode. First, the principle of the current / potential measuring device will be described.

As shown in FIG. 1, the anticorrosion object G is, for example, a pier in a structure such as a pile-type pier. The anticorrosion object G is, for example, a steel pipe pile constructed of steel pipes. The lower end of the anticorrosion object G is placed in the soil deeper than the seabed B (in the sea soil), and the floor slab D is supported at the upper end.

The anticorrosion object G is exposed to soil and water (seawater). A sacrificial anode P for anticorrosion is installed on the anticorrosion object G. Since the height of the seabed of the anticorrosion object G is different, the area (area) exposed to the soil and water differs depending on the position where it is placed. The anticorrosion state of the anticorrosion object G is determined by measuring the potential of the anticorrosion object G in the soil and the potential of the anticorrosion object G in water with the reference electrode M.

The anticorrosion state of the anticorrosion object G by the sacrificial anode P in water is determined, for example, by installing a collation electrode M that gives a reference point of the potential in water and measuring the potential of the anticorrosion object G with the collation electrode M. .. For example, the negative terminal of the measuring instrument S is connected to the reference electrode M, and the positive terminal of the measuring instrument S is connected to the anticorrosion object G.

Similarly, the anticorrosion state of the anticorrosion object G by the sacrificial anode P in the soil is determined by burying a collation electrode M that gives a reference point of the potential in the soil and measuring the potential of the anticorrosion object G with the collation electrode M. Will be done.

As shown in FIG. 2, when the anticorrosion object G is made of a steel material and is in an anticorrosion state by the sacrificial anode P, the potential of the anticorrosion object G is measured by the reference electrode M and the sea mercury / silver chloride collation is performed. When converted to the electrode reference, for example, a value of −780 (mV vs. Ag / AgCl [sw]) or less is shown.

At the pier, since a plurality of anticorrosion objects G are installed in a deep place on the land side, other anticorrosion objects other than the anticorrosion object G arranged along the front surface (landing side) of the deck D. For G, it is difficult to measure the potential with the reference electrode M. Therefore, the current / potential measuring device described below is applied to the pier.

As shown in FIG. 3, the current / potential measuring device 1 includes an electrode unit 10 formed in a rod shape, and a measuring unit 50 for determining the anticorrosion state of the anticorrosion object G using the electrode portion 10. The electrode portion 10 is inserted into the opening H provided in advance in the floor slab D.

The electrode portion 10 is installed in a corrosive environment substantially the same as that of the anticorrosion object G. Here, the corrosive environment substantially the same as the anticorrosion object G is, for example, pH, if it is in water, as compared with the environment in which the anticorrosion object G is installed even if it is not in the vicinity of the anticorrosion object G. Indicates positions where environment-related parameters such as chloride ion concentration, resistivity, temperature, dissolved oxygen concentration, flow velocity, water depth, and distance from land can be regarded as substantially the same. In this embodiment, the anticorrosion object is a steel pipe pile, and the position where the distance from the front surface (landing side) of the pier is the same is set as substantially the same corrosion environment as the anticorrosion object G.

The electrode portion 10 includes an electrode portion 11 for soil and an electrode portion 12 for underwater use. The electrode portion 11 for soil is used by being penetrated into the soil deeper than the seabed B. The electrode portion 11 for soil includes a probe electrode 11A electrically connected to an anticorrosion object and a collation electrode 11G connected to the probe electrode.

The probe electrode 11A is formed in a cylindrical shape having a circular cross section. The probe electrode 11A is made of substantially the same material as the anticorrosion object G. When the anticorrosion object G is a steel pipe pile made of a steel material, the probe electrode 11A is made of substantially the same steel material.

The probe electrode 11A has an insulating portion 11B covered with an insulating material on the surface side thereof. The insulating portion 11B is formed by being coated with a highly durable inorganic coating material such as a reinforced inorganic heavy-duty anticorrosion material containing carbon fiber. The insulating material may be ceramic in addition to the above-mentioned material. Even if it is an organic material, it may be a putty material or the like as long as it has a track record of being able to withstand long-term use. Any material may be used as long as it can insulate and coat the steel material for a long period of time. The probe electrode 11A has an exposed portion 11C having an exposed steel material formed on the lower end side. The exposed portion 11C is formed so as to have a predetermined area. The exposed portion 11C is buried in the soil deeper than the seabed B. On the upper end (other end) side of the probe electrode 11A, a terminal 11D that electrically conducts with the probe electrode 11A is provided. The terminal 11D is connected to the measuring unit 50.

A reference electrode 11G is electrically insulated and connected to the lower end (one end) side of the probe electrode 11A. The reference electrode 11G is formed in a columnar shape having the same diameter as the probe electrode 11A. The reference electrode 11G is made of, for example, zinc or a zinc alloy. The reference electrode 11G is concentrically connected to the probe electrode 11A. A washer 11H made of ceramic or silicon as an insulator is provided between the upper end of the reference electrode 11G and the lower end of the probe electrode 11A. The washer 11H is composed of, for example, a pair of silicon washers and a ceramic washer arranged between the pair of silicon washers.

A conductor 11K is connected to the upper end of the reference electrode 11G. The conductor 11K is formed, for example, into a rod-shaped body having a circular cross section made of copper. A male screw is formed at the lower end of the conductor 11K, and is screwed into a female screw hole formed on the upper surface of the reference electrode 11G. As a result, the reference electrode 11G and the conductor 11K are electrically connected. The conductor 11K is inserted inside the probe electrode 11A. For example, a glass tube 11L is inserted between the conductor 11K and the probe electrode 11A. As a result, the conductor 11K and the probe electrode 11A are electrically insulated from each other.

The upper end of the conductor 11K projects from the upper end of the probe electrode 11A. A male screw is formed at the upper end of the conductor 11K. A nut 11M is fastened to the upper end of the conductor 11K via a washer 11H made of ceramic and silicon as an insulator. As a result, the probe electrode 11A is sandwiched between the nut 11M at the upper end and the reference electrode 11G at the lower end, and is securely connected to the reference electrode 11G. The upper end of the conductor 11K is exposed to metal and functions as a terminal. The upper end of the conductor 11K is connected to the measuring unit 50.

A metal fitting 11I (penetration member) for driving into the soil is connected to the lower end of the reference electrode 11G. The metal fitting 11I is made of, for example, metal. The upper end of the metal fitting 11I and the lower end of the reference electrode 11G are connected. A washer 11H made of ceramic or silicon as an insulator is provided between the upper end of the metal fitting 11I and the lower end of the reference electrode 11G.

The upper end of the metal fitting 11I and the lower end of the reference electrode 11G are fixed by, for example, a ceramic rod bolt 11J serving as an insulator. As a result, the metal fitting 11I and the reference electrode 11G are electrically insulated from each other. The metal fitting 11I is formed in a tapered shape whose cross section decreases toward the lower end. The metal fitting 11I is formed in a conical shape with a sharp lower end so as to easily penetrate into the soil from the seabed B, for example. In addition to the cone, the metal fitting 11I may have any shape as long as it can penetrate into the soil without excavation, in addition to a triangular pyramid and a pyramid including a quadrangular pyramid. Further, as long as it is hard and functions as an intrusive member, it may be a non-metal, and examples thereof include a hard vinyl chloride resin.

Next, the electrode portion 12 for underwater will be described. The electrode portion 12 for underwater has basically the same structure as the electrode portion 11 for soil. Hereinafter, the description overlapping with the electrode portion 11 for soil will be omitted as appropriate. The electrode portion 12 for underwater is formed shorter than the electrode portion 11 for soil. The underwater electrode portion 12 includes a probe electrode 12A and a reference electrode 12G.

The probe electrode 12A is formed in a cylindrical shape having a circular cross section. The probe electrode 12A is made of substantially the same material as the anticorrosion object G. The probe electrode 12A has an insulating portion 12B covered with an insulating material on the surface side thereof. The probe electrode 12A has an exposed portion 12C on the lower end side where substantially the same material as the anticorrosion object G is exposed. The area of the exposed portion 12C when assumed to be used in water is, for example, about 100 cm ² , which is extremely small compared to the area of the anticorrosion object. Therefore, an electrocoating is formed in a relatively short period of time, and the inflowing current is It is reduced and reaches the same level of anticorrosion current density as the anticorrosion object G.

The exposed portion 12C is formed so as to have a predetermined area. The exposed portion 12C is exposed to water. On the upper end (other end) side of the probe electrode 12A, a terminal 12D that electrically conducts with the probe electrode 12A is provided. The terminal 12D is connected to the measuring unit 50.

A reference electrode 12G is electrically insulated and connected to the lower end (one end) side of the probe electrode 12A. The reference electrode 12G is made of, for example, zinc or a zinc alloy. The reference electrode 12G may be selected from other materials as long as it has requirements as a reference electrode such as no hysteresis and a large exchange current density other than zinc and zinc alloy. A washer 12H made of ceramic or silicon as an insulator is provided between the upper end of the reference electrode 12G and the lower end of the probe electrode 12A.

A conductor 12K is connected to the upper end of the reference electrode 12G. The reference electrode 12G and the conductor 12K are electrically connected. The conductor 12K is inserted inside the probe electrode 12A. A glass tube 12L is inserted between the conductor 12K and the probe electrode 12A. The upper end of the conductor 12K protrudes from the upper end of the probe electrode 12A.

A male screw is formed at the upper end of the conductor 12K. A nut 12M is fastened to the upper end of the conductor 12K via a washer 12H made of ceramic and silicon as an insulator. The upper end of the conductor 12K is exposed to metal and functions as a terminal. The upper end of the conductor 12K is connected to the measuring unit 50.

The measuring unit 50 measures the current flowing between the sacrificial anode P and the probe electrodes 11A and 12A, and measures the potentials of the probe electrodes 11A and 12A by the reference electrode 11G. The measuring unit 50 includes a current meter 51 that measures the current flowing between the sacrificial anode P and the probe electrodes 11A and 12A, a voltmeter 52 that measures the potential of the anticorrosion object G with the matching electrode 11G, and a matching electrode 12G. A voltmeter 53 for measuring the potential of the anticorrosion object G is provided. The ammeter 51, the voltmeter 52, and the voltmeter 53 may be an integrated device.

As shown in FIG. 4, the measuring unit 50 includes a calculation unit 54 for determining the corrosion protection state of the corrosion protection target G and a calculation unit based on the measurement results of the electrode unit 10 by the ammeter 51 and the voltmeters 52 and 53. A display unit 55 for displaying the determination result of 54 and a storage unit 56 for storing various data may be further provided.

The arithmetic unit 54 is realized by executing a program (software) by a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). Part or all of these functional parts may be realized by hardware such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), or software. It may be realized by the cooperation of hardware.

For example, the calculation unit 54 compares a predetermined standard with the measurement result, and determines the degree of wear of the sacrificial anode P, the necessity of replacement, and the anticorrosion state of the anticorrosion object G.

The display unit 55 performs a predetermined display based on the determination result of the calculation unit 54. The display unit 55 displays a display image on the screen prompting the replacement of the sacrificial anode P, the repair of the anticorrosion object G, and the like based on the determination result. The display unit 55 is, for example, a display device such as an LCD (Liquid Crystal Display), an organic EL (Electro Luminescence) display, or an LED (Light Emitting Diode) display.

The storage unit 56 is, for example, a storage device such as an HDD (Hard Disk Drive) or a flash memory. The calculation unit 54, the display unit 55, and the storage unit 56 may be realized by an information processing terminal such as a personal computer, a tablet terminal, or a smartphone. The information processing terminal may be connected to a network, or may output a determination result based on the measurement result of the electrode unit 10 transmitted by the network.

Next, a method of using the current / potential measuring device 1 will be described. The user inserts the rod-shaped electrode portion 10 through the opening H formed in the deck slab D (see FIG. 3). The user submerges the electrode portion 11 for soil in the sea, and after the metal fitting 11I of the electrode portion 11 for soil reaches the seabed B, the top of the electrode portion 11 is pushed downward and subsided by a predetermined distance for collation. The electrode 11G and the exposed portion 11C are buried in the soil.

The user closes the switch 51A of the electrode portion 11 to conduct the sacrificial anode P and the probe electrode 11A, and measures the probe current with the ammeter 51. The exposed portion 11C of the probe electrode 11A is formed in a constant area. Based on the current flowing into the exposed unit 11C, the calculation unit 54 calculates the anticorrosion current density required for designing the electric anticorrosion and predicting the life. The user measures the OFF potential of the probe electrode 11A with the voltmeter 52.

The user opens the switch 51A to electrically turn off the probe electrode 11A and the sacrificial anode P. Since the IR drop disappears immediately after the IR drop is turned off, the calculation unit 54 calculates the potential at the time when the IR drop disappears as the OFF potential of the probe electrode 11A. Similarly, the user arranges the other electrode portion 12 for underwater in water, and exposes the reference electrode 12G and the exposed portion 12C in water.

The user closes the switch 51B of the electrode unit 12, conducts the sacrificial anode P and the probe electrode 12A, and measures the probe current with the ammeter 51. The calculation unit 54 calculates the anticorrosion current density required for designing the electrocorrosion protection and predicting the life based on the current flowing into the exposed portion 12C of the probe electrode 12A and the area of the exposed portion 12C.

The user measures the OFF potential of the probe electrode 12A with the voltmeter 53. The user opens the switch 51B to electrically turn off the probe electrode 12A and the sacrificial anode P. The calculation unit 54 calculates the potential at the time of turning off as the OFF potential of the probe electrode 12A. The calculation unit 54 determines the anticorrosion state of the anticorrosion object G based on the measurement result, and the determination result is displayed on the display unit 55.

As described above, according to the current / potential measuring device 1, the insulating portion of the probe electrode is highly durable insulated by a predetermined covering material or the like, so that the maintenance cost can be reduced. According to the current / potential measuring device 1, since the structure and constituent materials of the device are composed of a simple structure consisting only of rods, pipes, and screws in consideration of workability and maintainability, workability, convenience, and maintenance are required. Sex improves.

According to the current / potential measuring device 1, since the electrode portion 10 is formed in a rod shape, the electrode portion 10 can be installed from the opening H formed in the deck D, and is installed in a deep place on the land side. It is possible to easily grasp the anticorrosion state of the anticorrosion object G such as a steel pipe pile and the degree of wear of the sacrificial anode.

According to the current / potential measuring device 1, since the reference electrode 11G is formed so as to be inserted into the soil, the workability at the time of installation can be improved. According to the current / potential measuring device 1, since the metal fitting 11I is provided on the reference electrode 11G, it can be easily inserted into the soil.

According to the current / potential measuring device 1, since the reference electrode and the probe electrode are integrally provided on the electrode portion 10, the electrode portion 10 can be easily installed at the time of measurement. According to the current / potential measuring device 1, the probe electrodes 11A and 12A function as electrodes through which current flows from the sacrificial anode P into the exposed portions 11C and 12C. According to the current / potential measuring device 1, since the exposed portions 11C and 12C are formed in a predetermined area, the anticorrosion current density required for the design of electric corrosion protection and the life prediction from the current flowing into the exposed portions 11C and 12C. Can be calculated.

According to the current / potential measuring device 1, in the probe electrodes 11A and 12A, the inflow current of the insulating portions 11B and 12B other than the exposed portions 11C and 12C changes when the insulating coating is peeled off and the exposed portion increases, and the anticorrosion current changes. Since the accuracy of the density is lowered, a highly durable insulating coating is applied by a coating material such as a reinforced inorganic heavy-duty anticorrosion material containing carbon fiber. According to the current / potential measuring device 1, since the reference electrodes 11G and 12G and the probe electrodes 11A and 12A are attached in the vicinity thereof, the influence of the error due to the IR drop can be reduced. In the above embodiment, the current / potential measuring device 1 grasps the anticorrosion state of the anticorrosion object G and the degree of wear of the sacrificial anode by using the two electrode portions of the electrode portion 11 and the electrode portion 12, but the present invention is not limited to this. If multiple electrodes are used in combination, more data can be obtained for each water depth. Further, the current / potential measuring device 1 for each of the soil and the water may be integrally formed. Further, the positional relationship between the reference electrodes 11G and 12G and the exposed portions 11C and 12C of the probe electrodes 11A and 12A may be upside down, and the metal fitting 11I (penetration member) itself may be the reference electrode 11G, 12G or the probe electrodes 11A and 12A. It may be formed as exposed portions 11C and 12C. At this time, the electrical connection inside the electrode portion 10 becomes a little complicated, but by using a durable material, workability, convenience, and maintainability can still be improved.

Next, other uses of the current / potential measuring device 1 will be described. Buried pipes, which are structures buried in the soil, are generally entirely covered with an insulating material. If the coating film formed by the insulating material is sound, the buried pipe will not corrode. However, if the coating film deteriorates over time and the metal base of the buried pipe is exposed, the pipe will corrode. Therefore, it is desirable that the covered buried pipe is electrically protected. The electrolytically protected coated pipe is regularly checked for corrosion protection by a reference electrode and maintained.

When the buried pipe is electrically protected by the sacrificial anode method, the coating of the buried pipe is in perfect condition, and the metal substrate is not exposed, no corrosion-proof current flows from the sacrificial anode. However, if a defect occurs in the coating film due to damage during construction or deterioration over time, an anticorrosion current according to the potential difference between the sacrificial anode and the buried pipe, soil resistivity, etc. will flow into the metal substrate, resulting in electrical anticorrosion. Is done. The current / potential measuring device 1 is also applied to grasp the corrosion protection state of the buried pipe and the degree of wear of the sacrificial anode. For example, the longer the distance between the buried pipe and the sacrificial anode, the more difficult it is for the anticorrosion current to flow.

Therefore, the electrode portion 10 of the current / potential measuring device 1 is embedded in a place where the anticorrosion current is difficult to reach, that is, at the midpoint between the adjacent sacrificial anode and the sacrificial anode and in the vicinity of the buried pipe farthest from the sacrificial anode. It is inserted so that it reaches the same depth as the center of the pipe. As a result, the required anticorrosion current (anticorrosion current density) and potential at that point can be confirmed by the current / potential measuring device 1, and the anticorrosion state of the anticorrosion object can be properly grasped. The area of the exposed portion 11C when it is assumed to be used for a covered buried pipe in the soil may be, for example, about 10 cm ² .

According to the current / potential measuring device 1 according to the embodiment, the anticorrosion current density can be calculated from the current measured for the steel pipe pile or the buried pipe. By comparing the above-mentioned anticorrosion current density with the current density assumed at the time of designing the electric anticorrosion, it is possible to grasp whether or not the consumption of the sacrificial anode is faster than the degree of consumption assumed at the time of design. For example, if the sacrificial anode wears faster than the degree of wear assumed at the time of design, the actual life of the sacrificial anode will be shorter than the design life. If the wear of the sacrificial anode is slower than the degree of wear assumed at the time of design, the actual life of the sacrificial anode will be longer than the design life.

It should be noted that all or a part of the functions of each unit included in the measurement unit 50 in the above-described embodiment is recorded on a computer-readable recording medium by recording a program for realizing these functions on the recording medium. It may be realized by loading the program into a computer system and executing it. The term "computer system" as used herein includes hardware such as an OS and peripheral devices.

Further, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, or a storage unit such as a hard disk built in a computer system. Further, a "computer-readable recording medium" is a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short period of time. It may also include a program that holds a program for a certain period of time, such as a volatile memory inside a computer system that is a server or a client in that case.

Further, the above-mentioned program may be for realizing a part of the above-mentioned functions, and may be further realized by combining the above-mentioned functions with a program already recorded in the computer system.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment and can be appropriately modified without departing from the spirit of the present invention. For example, in the above embodiment, in the current / potential measuring device 1, the electrode portion 10 is inserted into the opening H provided in advance in the deck D, but the opening H is the existing deck. It may be formed later on D to determine the anticorrosion state of the existing anticorrosion object G and the degree of wear of the sacrificial anode. Further, in the above embodiment, anticorrosion by the sacrificial anode P is exemplified, but in the present invention, the anticorrosion state and the anode (insoluble type) of the anticorrosion object to which an external power supply type anode is connected instead of the sacrificial anode. ) May be applied to grasp the current energized.

1 Current / potential measuring device, 10, 11, 12 electrode part, 11A, 12A probe electrode, 11B, 12B insulation part, 11C, 12C exposed part, 11D, 12D terminal, 11G, 12G collation electrode, 11H, 12H washer, 11I Metal fittings, 11J rod bolt, 11K, 12K conductor, 11L, 12L glass tube, 11M, 12M nut, 50 measuring unit, 51 current meter, 51A, 51B switch, 52, 53 voltmeter, 54 arithmetic unit, 55 display unit, 56 Storage part, B seabed, D floor slab, G anticorrosion object, H opening, M collation electrode, P sacrificial anode, S measuring instrument

Claims (10)

It is a current / potential measuring device that grasps the anticorrosion state of the anticorrosion object protected by the sacrificial anode and the degree of wear of the sacrificial anode.
A probe electrode placed in substantially the same corrosive environment as the anticorrosion object and electrically connected to the anticorrosion object, and a matching electrode electrically insulated from the probe electrode and connected to the probe electrode. With an electrode section and
A measuring unit for measuring the current flowing between the sacrificial anode and the probe electrode and measuring the potential of the probe electrode with the reference electrode is provided.
Current / potential measuring device. The probe electrode is formed in a rod shape with substantially the same material as the anticorrosion object, and has an insulating portion covered with an insulating material on the surface side and an exposed portion with the material exposed.
The current / potential measuring device according to claim 1. The exposed portion is formed so as to have a predetermined area.
The current / potential measuring device according to claim 2. In the electrode portion, the probe electrode and the reference electrode are integrally formed in a rod shape.
In the probe electrode, the exposed portion is formed on one end side, and the reference electrode is electrically insulated and connected.
The current / potential measuring device according to claim 2 or 3. The electrode portion is connected to the collation electrode to provide an intrusive member, and the collation electrode and the exposed portion are embedded in the soil.
The current / potential measuring device according to any one of claims 2 to 4. The reference electrode and the exposed portion are installed in water or soil.
The current / potential measuring device according to any one of claims 2 to 4. The electrode part buried in the soil and
With the other electrode portion installed in water,
The current / potential measuring device according to any one of claims 1 to 6. The measuring unit determines the anticorrosion state of the anticorrosion object based on the measurement result of the electrode unit.
The current / potential measuring device according to any one of claims 1 to 7. An external power supply type anode is connected in place of the sacrificial anode.
The current / potential measuring device according to any one of claims 1 to 8. It is an electrode for grasping the anticorrosion state of the anticorrosion object protected by the sacrificial anode and the degree of wear of the sacrificial anode.
A probe electrode placed in substantially the same corrosive environment as the anticorrosion object and electrically connected to the anticorrosion object,
An electrode comprising a reference electrode that is electrically insulated from the probe electrode and is connected to the probe electrode.

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