JP7101594B2 - Coating degradation detection system, coating degradation detection method and program - Google Patents

Description

The present invention relates to a coating degradation detection system, a coating degradation detection method and a program.

Techniques for monitoring the coating of steel materials have been proposed.
For example, Patent Document 1 describes a method for monitoring the durability of heavy anticorrosion coated steel materials used for rivers and marine structures. In this method, an electrode is provided that penetrates the steel body to be covered with heavy anticorrosion in the plate thickness direction, and the steel body and the electrode are insulated by an insulating material. Then, a coated conductor is attached to each of the steel body and the electrode, and the electrical resistance between these coated conductors is continuously measured. The primer and urethane elastomer, which are the heavy anticorrosion coating layer applied to the steel body, are peeled off and the water film penetrates to the position of the electrode, so that electrical conduction occurs between the coated conductors. This electrical continuity is detected.

Japanese Unexamined Patent Publication No. 2011-11249

In the method described in Patent Document 1, it is detected that the heavy anticorrosion coating layer is peeled off to the position of the electrode. On the other hand, if deterioration of the coating can be detected before the coating (coating layer) of the coating film or the like is peeled off, damage to the coating target (steel material or the like) can be prevented.

The present invention provides a coating deterioration detection system, a coating deterioration detection method and a program capable of detecting deterioration of a coating before peeling of the coating occurs.

According to the first aspect of the present invention, the coating deterioration detection system is a sensor provided on a monitored object having a surface coating, and two or more electrodes and each of the two or more electrodes are exposed. An insulating portion that separates the two or more electrodes and a coating portion that is formed of the same material as the surface coating and integrally covers the surface of the two or more electrodes and the insulating portion. A sensor provided with a monitoring target and the two or more electrodes separated by the insulating portion, a voltage applying portion for applying an AC voltage to the two or more electrodes, and the voltage applying portion applied the AC voltage. It is provided with an impedance acquisition unit for acquiring the impedance at the time.

The voltage application unit may apply voltages of three or more different frequencies, and the impedance acquisition unit may acquire real and imaginary components of impedance for each frequency.

The voltage application unit may apply a voltage at a frequency determined in advance so that the real and imaginary components of the impedance are plotted on the arc of the Nyquist diagram.

The voltage application unit may apply an AC voltage in the range of at least 100 millivolts to 10 volts to the two or more electrodes.

The voltage application unit may apply an AC voltage in the range of at least 300 millivolts to 3000 millivolts to the two or more electrodes.

According to the second aspect of the present invention, the coating deterioration detecting method is a sensor provided on a monitored object to which a surface coating is applied, and two or more electrodes and each of the two or more electrodes are exposed. An insulating portion that separates the two or more electrodes and a coating portion that is formed of the same material as the surface coating and integrally covers the surface of the two or more electrodes and the insulating portion. A step of applying an AC voltage to the two or more electrodes of a sensor provided with a monitoring target and the two or more electrodes separated by the insulating portion, and a step of acquiring an impedance when the AC voltage is applied. And, including.

In the step of applying the AC voltage, voltages of three or more different frequencies may be applied, and in the step of acquiring the impedance, the real number component and the imaginary number component of the impedance for each frequency may be acquired.

The voltage application unit may apply a voltage at a frequency determined in advance so that the real and imaginary components of the impedance are plotted on the arc of the Nyquist diagram.

In the preliminary test, the impedance may be acquired in an environment that accelerates the deterioration of the surface coating.

According to a third aspect of the present invention, the program is a sensor provided on a monitored object having a surface coating on a computer, and two or more electrodes and each of the two or more electrodes are exposed. An insulating portion that separates the two or more electrodes and a coating portion that is formed of the same material as the surface coating and integrally covers the surface of the two or more electrodes and the insulating portion. A step of applying an AC voltage to the two or more electrodes of a sensor provided with a monitoring target and the two or more electrodes separated by the insulating portion, and a step of acquiring an impedance when the AC voltage is applied. And, it is a program to execute.

According to the coating deterioration detection system, the coating deterioration detection method and the program described above, the deterioration of the coating can be detected before the peeling of the coating occurs.

It is a schematic block diagram which shows the example of the functional structure of the coating deterioration detection system which concerns on embodiment. It is a figure which shows the structural example of the sensor which concerns on embodiment. It is a figure which shows the installation example of the sensor which concerns on embodiment to the monitoring target. It is a figure which shows the example of the Nyquist diagram obtained in an embodiment. It is a figure which shows the example of the processing procedure in the preliminary test in an embodiment. It is a figure which shows the example of the impedance of the surface coating which concerns on embodiment. It is a figure which shows the structural example of the environment which accelerates the deterioration of a coating in an embodiment. It is a figure which shows the example of the processing procedure which determines the deterioration of a surface coating by the coating deterioration detection apparatus which concerns on embodiment.

Hereinafter, embodiments of the present invention will be described, but the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential to the means of solving the invention.
FIG. 1 is a schematic block diagram showing an example of a functional configuration of a coating deterioration detection system according to an embodiment. With the configuration shown in FIG. 1, the coating deterioration detection system 1 includes a sensor 100, a power supply device 200, and a coating deterioration detection device 300. The coating deterioration detection device 300 includes a communication unit 310, an operation input unit 320, a display unit 330, a storage unit 380, and a control unit 390. The control unit 390 includes a voltage application control unit 391, an impedance acquisition unit 392, and a deterioration determination unit 393.

The coating deterioration detection system 1 is a system for detecting deterioration of the surface coating applied to the monitored object. The monitoring target here is not limited to a specific one as long as it is coated to protect the monitoring target such as rust prevention. For example, the monitoring target may be a vehicle such as a ship, a vehicle, or an aircraft. Alternatively, the monitoring target may be a machine tool or a machine such as plant equipment. Alternatively, the monitoring target may be a structure such as a building.
The material to be monitored can be various materials such as steel, aluminum, magnesium, etc., which are coated for protection.
In the following, a case where a coating film (paint film) is formed as a surface coating to be monitored will be described as an example. However, the surface coating to be monitored is not limited to the coating film, and may be a coating artificially provided to protect the monitoring target and whose impedance changes due to deterioration.
The coating material (coating material) is not limited to a specific material. For example, the monitoring target may be coated with an epoxy-based coating material or may be coated with a urethane-based coating material.

The sensor 100 is a sensor for measuring impedance, and is used for detecting deterioration of the surface coating to be monitored. Although the sensor 100 is provided on the monitored object, the impedance of the surface coating of the monitored object is measured by measuring the impedance of the surface coating provided on the sensor 100 itself, instead of directly measuring the impedance of the surface coating of the monitored object. Is simulated.

FIG. 2 is a diagram showing a configuration example of the sensor 100.
FIG. 2 shows an example in which the sensor 100 is configured in the shape of a cylinder, and FIG. 2A (upper view) shows a schematic outline view of the sensor 100 when viewed from the side surface of the cylinder. The cross-sectional view inside the sensor 100 is shown superimposed. The upper side of FIG. 2A is the monitoring target side at the time of installation on the monitoring target.

In the example of FIG. 2, the sensor 100 includes a pin electrode 111, a ring electrode 112, an insulating portion 120, a coating portion 130, a first lead wire 141, and a second lead wire 142.
FIG. 2B (lower figure) is a schematic outline view when viewed from the side opposite to the monitoring target (lower side in FIG. 2A) when installed in the monitoring target, and is a cross section inside the sensor 100. The figures are overlaid.

In the configuration of FIG. 2, the ring-shaped ring electrode 112 is arranged around the cylindrical pin electrode 111. The combination of the pin electrode 111 and the ring electrode 112 corresponds to the example of two or more electrodes. The pin electrode 111 and the ring electrode 112 are collectively referred to as an electrode 110.
The number of electrodes included in the sensor 100 is not limited to the two exemplified in FIG. 2, and may be two or more. For example, the sensor 100 may include a grounding electrode in addition to a pair of electrodes such as a pin electrode 111 and a ring electrode 112. Further, the sensor 100 may include two or more pairs of electrodes.

The insulating portion 120 separates the pin electrode 111 and the ring electrode 112 so that each of the pin electrode 111 and the ring electrode 112 is exposed on the lower side of FIG. 2 (A). That is, the pin electrode 111 and the ring electrode 112 are not covered with the insulating portion 120 on the lower surface of FIG. 2A, and are covered with the insulating portion 120 other than the insulating portion 120. The pin electrode 111 and the ring electrode 112 are insulated by an insulating portion 120 except for the lower surface of FIG. 2A.

Further, the pin electrode 111 and the ring electrode 112 are insulated from the monitored object and its surface coating by the insulating portion 120 in a state where the sensor 100 is installed in the monitored object. Since the pin electrode 111 and the ring electrode 112 are insulated from the monitoring target, noise is not picked up from the monitoring target. According to the coating deterioration detection system 1, deterioration of the coating can be detected with high accuracy in this respect.

The coating portion 130 is formed of the same material as the surface coating to be monitored, and integrally covers the surface of the pin electrode 111 and the ring electrode 112 and the insulating portion 120 (particularly, the lower surface and the side surface of FIG. 2A). ..
In particular, on the lower surface of FIG. 2A, a coating with the same coating material as the surface coating to be monitored is formed as a part of the coating portion 130 with the same thickness as the surface coating to be monitored. The sensor 100 simulates the deterioration of the surface coating to be monitored by measuring the deterioration of the coating formed on the lower surface of FIG. 2A.

Both the first lead wire 141 and the second lead wire 142 are configured by using a coated conductor wire. The first lead wire 141 is connected to the pin electrode 111, and the second lead wire 142 is connected to the ring electrode 112. Further, the first lead wire 141 and the second lead wire 142 are connected to the power supply device 200, respectively.
The power supply device 200 corresponds to an example of a voltage application unit, and by applying a voltage between the first lead wire 141 and the second lead wire 142, a voltage is applied between the pin electrode 111 and the ring electrode 112. do.
The first lead wire 141 and the second lead wire 142 are collectively referred to as a lead wire 140.

When the coating on the lower surface of FIG. 2A deteriorates, its impedance changes. The coating deterioration detection system 1 acquires the impedance of the coating by applying an AC voltage between the pin electrode 111 and the ring electrode 112 and measuring the current, and detects the deterioration of the coating based on the obtained impedance. ..

However, the configuration of the sensor 100 is not limited to that illustrated in FIG. For example, both of the two electrodes may be configured in the shape of a pin electrode.
As the sensor 100, an existing sensor such as a two-pole atmospheric corrosion sensor can be used.

FIG. 3 is a diagram showing an example of installation of the sensor 100 on the monitoring target.
As described above, with the sensor 100 installed on the monitoring target 910, the pin electrode 111 and the ring electrode 112 are insulated from the monitoring target 910 and the surface coating 920 by the insulating portion 120.
In the configuration of FIG. 3, the first lead wire 141 extending from the pin electrode 111 and the second lead wire 142 extending from the ring electrode 112 are connected to the power supply device 200 and the measuring device 410, respectively.

The power supply device 200 applies an AC voltage between the pin electrode 111 and the ring electrode 112 via the first lead wire 141 and the second lead wire 142. The measuring device 410 has a current (coating portion 130) between the first lead wire 141 and the second lead wire 142 in a state where the power supply device 200 applies an AC voltage between the pin electrode 111 and the ring electrode 112. The current flowing between the pin electrode 111 and the ring electrode 112) is measured. The communication device 420 transmits the current measured value by the measuring device 410 to the coating deterioration detecting device 300.

The installation method of the sensor 100 on the monitoring target 910 is not limited to the installation method according to the configuration of FIG. For example, a part or all of the power supply device 200, the measuring device 410, and the communication device 420 may be integrally configured with the sensor 100. Alternatively, a part or all of the measuring device 410 and the communication device 420 may be installed inside the monitored object 910.
The coating deterioration detection device 300 may also be integrally configured with the sensor 100, or may be installed inside the monitoring target 910.
Further, the first lead wire 141 and the second lead wire 142 may be connected to the coating deterioration detecting device 300 so that the coating deterioration detecting device 300 measures the current. In this case, the measuring device 410 and the communication device 420 are unnecessary.

FIG. 3 shows an example in which the sensor 100 is installed after the surface coating 920 is applied to the monitoring target 910, and the surface coating 920 exists between the monitoring target 910 and the sensor 100. In this way, after the surface coating 920 is applied to the monitored object 910, the sensor 100 can be installed by so-called retrofitting. Therefore, the coating deterioration detection system 1 can be applied to the existing monitoring target 910.
Alternatively, the surface coating 920 may be applied after the sensor 100 is installed on the monitoring target 910. In this case, the coating portion 130 is applied to the sensor 100 by applying the surface coating 920 to the monitoring target 910, and it is not necessary to perform a separate process for providing the coating portion 130 on the sensor 100.

The sensor 100 is installed in a portion of the monitoring target 910 where visibility or accessibility is poor and / or where the corrosive environment is severe. This makes it possible to compensate for the oversight of deterioration of the coating by visual confirmation. The number of sensors 100 installed in one monitoring target 910 may be one or more. For example, when the monitoring target 910 has a plurality of locations having poor visibility or accessibility, the sensor 100 may be installed in each of the plurality of locations.

The power supply device 200 applies an AC voltage in the range of at least 100 millivolts (mV) to 10 volts (V) between the pin electrode 111 and the ring electrode 112. More preferably, the power supply 200 applies an AC voltage between the pin electrode 111 and the ring electrode 112 in the range of at least 300 millivolts to 3000 millivolts.

Here, in the technique for detecting the peeling of the coating material, a relatively low voltage of about 10 millivolts to 20 millivolts is used in order to monitor the occurrence of corrosion of the steel material.
On the other hand, the coating deterioration detection system 1 detects deterioration at the initial stage of deterioration of the surface coating 920. In other words, the coating deterioration detection system 1 detects the deterioration of the coating at a stage prior to the occurrence of corrosion of the steel material.
Therefore, the power supply device 200 applies a voltage higher than the voltage (about 10 millivolts to 20 millivolts described above) in the case of detection at the stage where the deterioration of the coating has progressed, such as the detection of peeling of the coating.

At the stage where the deterioration of the coating has progressed, it is considered that the coated target device (monitoring target 910 in this embodiment) is damaged. In this case, it is necessary to remove the coating once to clean the target device and then reapply the coating, which requires time for maintenance and places a heavy burden on the maintenance worker. Also, the target device cannot be moved during maintenance.

On the other hand, by detecting the initial stage of coating deterioration by the coating deterioration detection system 1, it is possible to detect and perform maintenance before damage occurs to the monitored object 910 without performing excessive maintenance. The rice cycle cost of the monitored target 910 can be reduced in that excessive maintenance can be avoided and relatively simple maintenance such as maintenance of the coating is required.

The power supply 200 may apply voltages of three or more different frequencies. If the arc in the Nyquist diagram can be estimated by measuring the impedance at three or more different frequencies, the degree of deterioration of the surface coating 920 can be evaluated based on the diameter of the arc.

FIG. 4 is a diagram showing an example of a Nyquist diagram. The horizontal axis of the graph of FIG. 4 shows the real component impedance (Re | Z |) between the pin electrode 111 and the ring electrode 112 (of the coating). The vertical axis indicates the imaginary component impedance (Re | Z |).
Lines L11 and L12 show examples of Nyquist plots. Line L11 shows the arc portion of the Nyquist diagram. Line L12 indicates a straight line portion of the Nyquist diagram.

Both the lines L13 and L14 are lines that extend the arc of the line L11.
The distance D11 indicates the diameter of the arc (lines L11, L13 and L14) indicated by the Nyquist diagram. This distance D11 indicates the coating film resistance (the real part of the response resistance), and it can be evaluated that the larger the distance D11, the larger the resistance value of the coating and the smaller the degree of deterioration.

The right side of the graph has a low measurement frequency (frequency of the AC voltage applied between the pin electrode 111 and the ring electrode 112), and the left side has a high measurement frequency. At points P1 to P3, point P1 has the highest measurement frequency, then point P2 has the highest measurement frequency, and point P3 has the lowest measurement frequency.
By measuring the impedance while changing the measurement frequency and measuring, for example, three points P1 to P3, an arc in the Nyquist diagram can be estimated and the diameter of the arc can be calculated.

Since there is a part where the Nyquist diagram does not form an arc like line L12, and the Nyquist diagram may not form an arc depending on the measured voltage, the measured voltage and measurement frequency are determined by a preliminary test. I will do it.
In the preliminary test, for the surface coating 920 with the coating material to be measured, a sample having several stages of deterioration such as large, medium, and small is prepared. Then, for each degree of deterioration, the impedance is measured at various frequencies for each of several voltages such as, for example, an applied voltage of 10 millivolts (mV), 100 millivolts, 500 millivolts, and 1000 millivolts, and frequency characteristics are detected.

By drawing a Nyquist diagram based on the obtained frequency characteristics, it is possible to determine the voltage and frequency that are points on the arc of the Nyquist diagram according to the degree of deterioration. This causes the power supply 200 to apply a voltage at a frequency determined in advance so that the real and imaginary components of the impedance are plotted on the arc of the Nyquist diagram.

FIG. 5 is a diagram showing an example of a processing procedure in a preliminary test.
In the process of FIG. 5, the test worker prepares a sample having several stages of deterioration, for example, large, medium, and small, for each of the coating materials to be measured (step S101). Then, the process of step S102 or less is performed for each prepared sample (hence, for each coating material and each degree of deterioration).

Next, the test worker sets the temperature environment and the humidity environment (step S102). This is to perform tests at various temperatures and humidity so that deterioration of the surface coating 920 can be detected regardless of temperature and humidity.
Next, the test worker sets the applied voltage (step S103). The test worker sets the applied voltage to a preset voltage, for example, in the range of 10 millivolts to 1000 millivolts.

Then, the test worker measures the impedance between the pin electrode 111 and the ring electrode 112 (hence, the impedance of the sample of the surface coating 920) (step S104).
Further, the test worker evaluates the detection of the coating film resistance (step S105). The coating film resistance is indicated by the diameter of the arc drawn by the Nyquist curve, as shown at the distance D11 in FIG.

When it is determined in step S105 that the coating film resistance cannot be detected (step S105: cannot be detected), the test operator resets the applied voltage (step S111) and repeats the process from step S104.
On the other hand, when it is determined in step S105 that the coating film resistance can be detected (step S105: detectable), the test operator evaluates the frequency characteristics in the test and applies the applied frequency (between the pin electrode 111 and the ring electrode 112). (Frequency of the AC voltage applied to) is determined (step S121).

Then, the test worker monitors the change in impedance with time (step S122).
Then, the test worker determines whether or not the processing has been performed for all the temperature and humidity environments to be set (step S123).

When it is determined that there is an unset temperature / humidity environment (step S123: NO), the operator resets the temperature / humidity environment to the unset temperature / humidity environment (step S131), and repeats the process from step S103.
On the other hand, when it is determined in step S123 that the processing has been performed for all the temperature and humidity environments to be set (step S123: YES), the processing of FIG. 5 is terminated.

Alternatively, the coating deterioration detection system 1 may determine the deterioration of the surface coating 920 directly from the impedance measurement value without relying on the Nyquist diagram. In this case, the relationship between the voltage and frequency at which deterioration of the surface coating 920 is easily detected, the impedance at the voltage and frequency, and the degree of deterioration of the surface coating 920 is determined by a preliminary test.

FIG. 6 is a diagram showing an example of the impedance of the surface coating 920. The horizontal axis of the graph of FIG. 6 indicates the frequency of the applied voltage, and the vertical axis indicates the impedance (| Z | / Ω) of the surface coating 920.
Each of the lines L21 to L24 shows the frequency characteristic of the impedance (relationship between the frequency of the applied voltage and the impedance of the surface coating 920) at a certain degree of deterioration. The degree of deterioration of the line L21 is the smallest, and the degree of deterioration is gradually increased in the order of the lines L22, L23, and L24. Therefore, as the deterioration of the surface coating 920 progresses, the impedance of the surface coating 920 becomes smaller.

Referring to FIG. 6, the change in impedance due to the deterioration of the surface coating 920 is large near 0.1 hertz (Hz). Therefore, the frequency of the voltage applied by the power supply device 200 between the pin electrode 111 and the ring electrode 112 can be determined to be 0.1 hertz.
Generally, when the frequency of the applied voltage is high, the impedance can be measured stably, but the change in impedance due to the deterioration of the coating is relatively unlikely to appear. On the other hand, when the frequency of the applied voltage is low, the impedance measurement becomes unstable, but the change in impedance due to the deterioration of the coating is relatively likely to appear.

The coating deterioration detection device 300 detects the deterioration of the surface coating 920 by measuring the impedance with the sensor 100. The coating deterioration detection device 300 is configured by using a computer such as a personal computer or a workstation.
The communication unit 310 communicates with other devices. In particular, the communication unit 310 receives the measured value of the impedance by the sensor 100. Further, the communication unit 310 transmits an instruction of the output voltage and the output frequency to the power supply device 200.

The operation input unit 320 includes an input device such as a keyboard and a mouse, and accepts user operations. For example, the operation input unit 320 accepts an input operation of a determination threshold value for detecting deterioration of the surface coating 920.
The display unit 330 includes a display screen such as a liquid crystal panel or an LED (Light Emitting Diode) panel panel, and displays various images. For example, when the coating deterioration detecting device 300 detects the deterioration of the surface coating 920, the display unit 330 displays an alarm message indicating the deterioration of the coating deterioration detecting device 300.

The storage unit 380 stores various data. The storage unit 380 is configured by using the storage device included in the coating deterioration detection device 300.
The control unit 390 controls each unit of the coating deterioration detection device 300 to perform various processes. The control unit 390 is configured by a CPU (Central Processing Unit) included in the coating deterioration detection device 300 reading a program from the storage unit 380 and executing the program.

The voltage application control unit 391 controls the power supply device 200 to apply an AC voltage having a voltage and a frequency determined in a preliminary test between the pin electrode 111 and the ring electrode 112.
The impedance acquisition unit 392 acquires the impedance when the power supply device 200 applies an AC voltage between the pin electrode 111 and the ring electrode 112. For example, the impedance acquisition unit 392 acquires the real number component and the imaginary number component of the impedance for each frequency applied by the power supply device 200 from the sensing data received from the sensor 100 by the communication unit 310.

The deterioration determination unit 393 detects the deterioration of the surface coating 920 described above. The deterioration determination unit 393 determines whether or not the deterioration of the surface coating 920 is equal to or higher than the preset degree of deterioration. For example, the deterioration determination unit 393 calculates the coating film resistance indicated by the diameter of the arc of the Nyquist diagram, and compares the coating film resistance with a predetermined threshold value. When the coating film resistance is smaller than the threshold value, the deterioration determination unit 393 determines that the deterioration of the surface coating 920 is equal to or higher than the preset deterioration degree, and displays an alarm message indicating the deterioration of the surface coating 920 on the display unit 330. Display.

An environment that accelerates the deterioration of the coating may be used in order to efficiently perform a preliminary test for determining the applied voltage and frequency by the power supply 200.
FIG. 7 is a diagram showing a configuration example of an environment that accelerates the deterioration of the coating.
The deterioration acceleration environment 500 shown in FIG. 7 is controlled by a sensor 100, an oil bath 511, an oil 512, a glass container 521, a deterioration acceleration liquid 522, a thermocouple 530, a cooler 540, and a data logger 551. A personal computer (PC) 552 and a potentiostat / FRA553 are provided.

The oil 512 is put in the oil bath 511, and the glass container 521 is immersed in the oil 512. The oil bath 511 and the oil 512 are provided to stabilize the temperature inside the glass container 521.
The deterioration accelerating liquid 522 is put in the glass container 521, and the sensor 100 is immersed in the deterioration accelerating liquid 522. The deterioration accelerator 522 deteriorates the coating portion 130 of the sensor 100.

As the deterioration accelerating liquid 522, for example, a liquid obtained by mixing 50 grams of sodium chloride, 10 ml of acetic acid, 5 grams of hydrogen peroxide, and 1 L of distilled water can be used, but is not limited thereto.
Instead of the deterioration accelerating liquid 522, the coating portion 130 may be deteriorated by irradiation with ultraviolet rays.

The thermocouple 530 measures the temperature of the deterioration accelerator 522. The temperature measured by the thermocouple 530 is recorded in the data logger 551.
The cooler 540 cools the inside of the glass container 521 when the temperature of the deterioration accelerating liquid measured by the thermocouple 530 is too high.
The data logger 551 has various data such as the voltage and frequency applied to the sensor 100 and the current measured by the sensor 100 (current flowing between the pin electrode 111 and the ring electrode 112) in addition to the temperature measured value by the thermocouple 530. To record.

The control personal computer 552 instructs the potentiostat / FRA553 of the voltage and frequency applied to the sensor 100.
The Potentiostat / FRA553 is used in place of the power supply 200 to apply a voltage to the sensor 100. The potentiostat / FRA553 controls the voltage and frequency at the electrodes of the sensor 100 to the voltage and frequency instructed by the control personal computer 552 regardless of the state of the deterioration accelerating liquid 522.
When the deterioration acceleration environment 500 is used, the deterioration of the coating portion 130 is accelerated, whereby the applied voltage and frequency for each degree of deterioration of the coating portion 130 can be efficiently determined.

When the applied voltage and frequency are determined by conducting a test in an environment different from the actual environment as in the example of FIG. 7, it is preferable to confirm the validity of the determined applied voltage and frequency in the actual environment. The actual environment referred to here is an environment in which the coating deterioration detection system 1 is actually used to detect deterioration of the surface coating 920 of the monitoring target 910, that is, an environment in which the monitoring target 910 is actually operated.

Next, the operation of the coating deterioration detection device 300 will be described with reference to FIG.
FIG. 8 is a diagram showing an example of a processing procedure in which the coating deterioration detecting device 300 determines deterioration of the surface coating 920. The coating deterioration detecting device 300 performs the processing of FIG. 8 at regular intervals, for example. Alternatively, the coating deterioration detection device 300 may perform the process of FIG. 8 in response to a user operation instructing execution of the process.
In the process of FIG. 8, the voltage application control unit 391 sets the voltage and frequency of the AC voltage applied to the sensor 100 by the power supply device 200 to a preset combination of voltage and frequency, and controls the power supply device 200. And apply an AC voltage (step S201).

Next, the impedance acquisition unit 392 acquires the impedance measurement value (AC voltage between the pin electrode 111 and the ring electrode 112) by the sensor 100 in a state where the power supply device 200 applies an AC voltage to the sensor 100. (Step S202).
Next, the voltage application control unit 391 determines whether or not the application of the AC voltage to the sensor 100 and the acquisition of the impedance have been completed for all the combinations preset for the voltage and frequency (step S203).

When it is determined that there is an unset voltage and frequency combination (step S203: NO), the voltage application control unit 391 sets the voltage and frequency of the AC voltage applied to the sensor 100 by the power supply device 200 to the unset voltage and frequency. The frequency combination is set, and the power supply device 200 is controlled to apply an AC voltage (step S211).
After step S211 the process returns to step S202.

On the other hand, when the voltage application control unit 391 determines in step S203 that all the preset combinations of voltage and frequency have been set (step S203: YES), the deterioration determination unit 393 of the coating unit 130 The degree of deterioration is detected (step S221). The degree of deterioration of the coating portion 130 is used as a simulation of the degree of deterioration of the surface coating 920.
The deterioration determination unit 393 may calculate the diameter of the arc drawn by the Nyquist diagram as the degree of deterioration as described with reference to FIG. Alternatively, the deterioration determination unit 393 may directly use the obtained impedance as the degree of deterioration, such as using the magnitude of the impedance obtained in step S202 as the degree of deterioration.

Next, the deterioration determination unit 393 determines whether or not the degree of deterioration detected in step S221 is larger than the threshold value (step S222). The large degree of deterioration here means that the deterioration is progressing.
When it is determined that the degree of deterioration is larger than the threshold value (step S222: YES), the deterioration determination unit 393 controls the display unit 330 and displays a warning message on the display unit 330 indicating that the deterioration of the surface coating 920 has been detected. (Step S231).
After step S231, the coating deterioration detection device 300 ends the process of FIG.
Alternatively, when it is determined in step S222 that the degree of deterioration is equal to or less than the threshold value (step S222: NO), the coating deterioration detection device 300 ends the process of FIG.

As described above, the sensor 100 is provided on the monitored object 910 to which the surface coating 920 is applied. In the sensor 100, the insulating portion 120 separates the two or more electrodes 110 so that each of the two or more electrodes 110 (in the example of FIG. 2, the pin electrode 111 and the ring electrode 112) is exposed. The coating portion 130 is formed of the same material (coating material) as the surface coating 920, and integrally covers each of the two or more electrodes 110 and the surface of the insulating portion 120. The sensor 100 is provided with the monitoring target 910 and each of the two or more electrodes 110 separated by an insulating portion 120. The power supply device 200 applies an AC voltage to two or more electrodes 110 of the sensor 100. The impedance acquisition unit 392 acquires the impedance when the power supply device 200 applies an AC voltage.

In this way, the sensor 100 is installed in the monitoring target 910. By installing the sensor 100 in a portion of the monitoring target 910 where visibility or accessibility is poor and / or in a location where the corrosive environment is severe, it is possible to compensate for the oversight of coating deterioration in visual confirmation.
Further, since the electrode 110 and the monitoring target 910 are insulated by the insulating portion 120, the sensor 100 does not pick up the noise from the monitoring target 910. According to the coating deterioration detection system 1, deterioration of the surface coating 920 can be detected with high accuracy in this respect.

Further, the power supply device 200 applies voltages having three or more different frequencies. The impedance acquisition unit 392 acquires the real number component and the imaginary number component of the impedance for each frequency.
By acquiring impedances for a plurality of different frequencies by the impedance acquisition unit 392, the deterioration determination unit 393 can determine the deterioration of the surface coating 920 with higher accuracy.
Further, the impedance acquisition unit 392 acquires the real number component and the imaginary number component of the impedance for three or more different frequencies, so that the deterioration determination unit 393 can estimate the Nyquist diagram. In particular, the deterioration determination unit 393 estimates the arc drawn by the Nyquist diagram and calculates the diameter of the arc, so that the calculated diameter can be used as an index value for deterioration of the surface coating 920. As the deterioration progresses, the diameter becomes smaller.

The power supply 200 also applies a voltage at a frequency determined in advance so that the real and imaginary components of the impedance are plotted on the arc of the Nyquist diagram.
As a result, the deterioration determination unit 393 can estimate the arc drawn by the Nyquist diagram and calculate the diameter of the arc, and use the calculated diameter as an index value for deterioration of the surface coating 920 as described above. be able to.

Further, according to the coating deterioration detection system 1, deterioration can be detected in the initial stage of deterioration of the surface coating 920 by using a relatively high voltage in the range of 100 millivolts to 10 volts applied by the power supply device 200. .. More preferably, the power supply 200 applies a voltage in the range of 300 millivolts to 3000 millivolts.
At the stage where the deterioration of the coating has progressed, it is considered that the coated target device (monitoring target 910 in this embodiment) is damaged. In this case, it is necessary to remove the coating once to clean the target device and then reapply the coating, which requires time for maintenance and places a heavy burden on the maintenance worker. Also, the target device cannot be moved during maintenance.

By detecting the initial stage of coating deterioration, the coating deterioration detection system 1 can detect and perform maintenance before damage occurs to the monitored object 910 without performing excessive maintenance. According to the coating deterioration detection system 1, the rice cycle cost of the monitored target 910 can be reduced in that excessive maintenance can be avoided and relatively simple maintenance such as maintenance of the coating is required.
Further, in the coating deterioration detection system 1, it is not necessary to use an electrolytic solution or the like when measuring the deterioration of the coating. Therefore, according to the coating deterioration detection system 1, it is possible to avoid the influence on the coating due to the use of the electrolytic solution at the time of measurement.

A program for realizing all or part of the functions of the control unit 390 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into the computer system and executed. May be processed. The term "computer system" as used herein includes hardware such as an OS and peripheral devices.
Further, the "computer system" includes the homepage providing environment (or display environment) if the WWW system is used.
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, and a storage device such as a hard disk built in a computer system. Further, the above-mentioned program may be for realizing a part of the above-mentioned functions, and may be further realized for realizing the above-mentioned functions in combination with a program already recorded in the computer system.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment and includes design changes and the like within a range not deviating from the gist of the present invention.

1 Coating deterioration detection system 100 Sensor 111 Pin electrode 112 Ring electrode 120 Insulation part 130 Coating part 141 First lead wire 142 Second lead wire 200 Power supply device 300 Coating deterioration detection device 310 Communication unit 320 Operation input unit 330 Display unit 380 Storage unit 390 Control unit 391 Voltage application control unit 392 Impedance acquisition unit 393 Deterioration judgment unit

Claims (10)

A sensor provided on a monitored object having a surface coating, the two or more electrodes, an insulating portion that separates the two or more electrodes so that each of the two or more electrodes is exposed, and the surface thereof. It is formed of the same material as the coating and includes the two or more electrodes and a coating portion that integrally covers the surface of the insulating portion, and the monitoring target and the two or more electrodes are separated by the insulating portion. With the sensors provided
A voltage application unit that applies an AC voltage to the two or more electrodes,
An impedance acquisition unit that acquires impedance when the voltage application unit applies the AC voltage, and an impedance acquisition unit.
A coating deterioration detection system. The voltage application unit applies voltages of three or more different frequencies to the voltage application unit.
The impedance acquisition unit acquires the real number component and the imaginary number component of the impedance for each frequency.
The coating deterioration detection system according to claim 1. The voltage application section applies a voltage at a frequency determined in advance so that the real and imaginary components of the impedance are plotted on the arc of the Nyquist diagram.
The coating deterioration detection system according to claim 2. The voltage application unit applies an AC voltage in the range of at least 100 millivolts to 10 volts to the two or more electrodes.
The coating deterioration detection system according to any one of claims 1 to 3. The voltage application unit applies an AC voltage in the range of at least 300 millivolts to 3000 millivolts to the two or more electrodes.
The coating deterioration detection system according to claim 4. A sensor provided on a monitored object with a surface coating, the two or more electrodes, an insulating portion that separates the two or more electrodes so that each of the two or more electrodes is exposed, and the surface thereof. It is formed of the same material as the coating, and includes the two or more electrodes and a coating portion that integrally covers the surface of the insulating portion, and the monitoring target and the two or more electrodes are separated by the insulating portion. The step of applying an AC voltage to the two or more electrodes of the provided sensor, and
The process of acquiring the impedance when the AC voltage is applied and
Coating deterioration detection method including. In the step of applying the AC voltage, three or more different frequency voltages are applied, and the voltage is applied.
In the step of acquiring the impedance, the real number component and the imaginary number component of the impedance for each frequency are acquired.
The coating deterioration detection method according to claim 6. In the step of applying the AC voltage, a voltage having a frequency determined in the preliminary test is applied so that the real and imaginary components of the impedance are plotted on the arc of the Nyquist diagram.
The coating deterioration detection method according to claim 7. In the preliminary test, the impedance is acquired in an environment that accelerates the deterioration of the surface coating.
The coating deterioration detection method according to claim 8. On the computer
A sensor provided on a monitored object with a surface coating, the two or more electrodes, an insulating portion that separates the two or more electrodes so that each of the two or more electrodes is exposed, and the surface thereof. It is formed of the same material as the coating, and includes the two or more electrodes and a coating portion that integrally covers the surface of the insulating portion, and the monitoring target and the two or more electrodes are separated by the insulating portion. The step of applying an AC voltage to the two or more electrodes of the provided sensor, and
The process of acquiring the impedance when the AC voltage is applied and
A program to execute.

Images