JP2678223B2 - Corrosion environment monitoring method and device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a corrosive environment monitoring method and apparatus suitable for monitoring corrosiveness of environment and corrosion of members arranged in the environment.

[Conventional technology]

Well-known methods for monitoring the corrosion of equipment and structures or the corrosiveness of the environment are as discussed in "Detection and Prediction of Abnormalities", pages 61 to 65, published by the Industrial Research Board, edited by Hiroo Yamazaki. There is a method in which a probe in which a corrosion test piece is embedded as a sensor is installed in a device to be monitored, and the amount of thinning of the corrosion test piece is determined from the change in the electrical resistance of the sensor due to corrosion. This method is effective for tracking corrosion behavior over a long period of time, but has a drawback of slow response as a real-time sensor.

Further, as an attempt to improve such responsiveness, Japanese Patent Laid-Open No.
As shown in −490, there is a device that stacks multiple corrosion test pieces and monitors the amount of corrosion from the dimensional change of the corrosion test pieces.

[Problems to be solved by the invention]

However, the technology described in “Abnormality detection and prediction” has a slow response as a sensor, and has the drawback that it is difficult to detect when corrosion does not progress uniformly, such as crevice corrosion and pitting corrosion, which are the most problematic problems in corrosion. It was

Further, in the technique described in JP-A-63-490, it is necessary to increase the number of test pieces used in order to increase the detection sensitivity.
For example, when using a displacement measuring means with a resolution of 2 μm, it is necessary to measure the amount of corrosion with a sensitivity of 10 nm (20 nm on both sides of the test piece).
Zero test pieces are required. Therefore, it is necessary to manufacture 100 identical test pieces for high-sensitivity measurement, and when monitoring corrosion and the environment in several places of the same device, sensor manufacture is very expensive. Further, the above-mentioned conventional technique is suitable for detecting uniform corrosion in mild steel in the atmosphere, soil or concrete, and for detecting local corrosion of corrosion resistant materials such as stainless steel, aluminum alloys, copper alloys and nickel-based alloys. Not suitable.

An object of the present invention is to detect a corrosion in a gap formed in a member, which is also applicable to the detection of local corrosion of a corrosive material and has a fast response and a highly sensitive corrosion environment monitoring method and the same. To provide a device.

[Means for solving the problem]

In order to achieve the above object, the corrosive environment monitoring method of the present invention is characterized by measuring a stress change of the member due to an increase in volume due to a corrosion product generated in a gap portion formed by the member.

Further, in order to achieve the above object, the corrosion environment monitoring apparatus of the present invention is a member that constitutes a crevice, and a measurement that responds to a stress change of the member due to a volume change due to a corrosion product generated in the crevice. It is characterized by including means.

The member forming the gap of the corrosive environment monitoring device may be composed of a compressed spiral coil, a compressed spiral coil, a comb tooth, or a folded foil, or formed on a certain member. Other members for accelerating corrosion may be inserted in the formed gap.

As the stress measuring means in the corrosive environment monitoring device, it is preferable to use an electromechanical load converter, for example, a piezoelectric converter.

Further, in order to achieve the above object, another method for monitoring a corrosive environment is characterized by measuring a mass change of the member due to a corrosion product generated in a gap achieved in the member.

Further, in order to achieve the above object, another corrosive environment monitoring device includes a member that achieves a gap and a measuring unit that responds to a change in mass of the member due to a corrosion product generated in the gap. There is something I did.

A crystal unit is often used as a measuring unit that responds to a change in mass, and in that case, it is convenient to configure the member forming the gap portion from a thin film laminated on the crystal unit and another member in contact with the thin film. Further, the other member may be made of a material that is electrochemically more noble than the thin film.

In a corrosive environment monitoring device for measuring mass change, the member forming the gap may be composed of fine particles and other members in contact with the fine particles, in which case the fine particles are made of graphite as a corrosion accelerator. Is good. Other,
In order to form the gap using the corrosion accelerator, the member forming the gap may be composed of graphite-based fiber, wool or gasket, and other members in contact therewith.

In a corrosive environment monitoring device for measuring a stress change due to a corrosion product generated in the gap and a mass change due to the corrosion product, a temperature sensor for temperature compensating a measurement value by the measuring means. Should be provided.

Furthermore, the various corrosive environment monitoring devices listed above are suitable for water quality monitoring systems that respectively measure the corrosion of water and detect the deterioration of water quality from the degree of corrosion progress of the water. In this case, any one type of corrosion Multiple environmental monitoring devices are installed in the plant, and the measured values obtained by the corrosive environmental monitoring device are CR.
It is preferable to display the measured values in correspondence with the drawing of the plant drawn on the T screen. Then, it is convenient for safety if the statistical distribution of the measured value is evaluated and an abnormal value of the measured value is detected.

Further, if a large number of any one of the above corrosive environment monitoring devices are arranged in an array and the measured values obtained from the corrosive environment monitoring device are statistically processed, accurate data can be obtained.

The above-mentioned corrosive environment monitoring devices are applied to large-capacity magnetic storage devices, and the corrosiveness of the installation environment is measured,
An alarm can be displayed on the CRT when the measured corrosivity reaches a predetermined value, or the corrosive environment monitoring device can be applied to a large computer to monitor the corrosiveness of the cooling medium for cooling the internal elements. An alarm may be displayed on the CRT when it is detected and the measured corrosivity reaches a predetermined value.

[Action]

INDUSTRIAL APPLICABILITY The corrosion environment monitoring method and apparatus of the present invention utilize acceleration of corrosion in the gap and increase in volume or mass in the gap due to formation of corrosion products.
That is, in the gap, it becomes difficult to replenish oxygen, so that the corrosion resistant oxide film cannot be maintained, and it becomes more likely to be electrochemically corroded than the free surface, and the corrosion is accelerated.

Here, the gap means a minute gap of several hundred μm or less formed between the surface of a test piece and the surface of another part of the same test piece or the surface of another member, and water is formed by capillary action. Refers to the intruder. Oxygen is deficient in such gaps, so materials such as stainless steel, aluminum alloys, nickel-based alloys, and titanium alloys that exhibit corrosion resistance due to the presence of corrosion-resistant oxide coatings cannot maintain the oxide coatings. It is known that the corrosion proceeds at a corrosion rate that is several orders of magnitude higher than that of a non-free surface. Further, since the corrosion products generated by corrosion are metal oxides, hydrated oxides, and hydroxides, the volume and weight increase as compared with the metal state.

In the present invention, the change in stress acting on the test piece due to the increase in the volume of the corrosion product in the gap is measured by a strain gauge, a piezoelectric element or the like. In order to perform highly sensitive measurement, it is effective to increase the number of gaps formed in the test piece.

The mass increase is measured by utilizing the fact that the natural frequency of the crystal unit changes due to the change of the mass. That is, when the thin film deposited on the crystal unit is corroded and oxidized to increase its weight, the natural frequency changes in proportion to the mass change. For a 6MHz oscillator, the change in frequency at 1Hz is 1.23
This corresponds to a mass change of × 10 ^-8 g / cm ² and can be measured with extremely high sensitivity.

Therefore, it is possible to monitor the change in the corrosiveness of the environment by monitoring the corrosion rate in the gap portion, and it is also possible to monitor the corrosion by configuring the test piece with the same material composition as the member to be monitored.

〔Example〕

Before describing the embodiments of the present invention, the operating principle of the present invention will be described. FIG. 1 is a diagram showing the operating principle of the present invention.

The corrosive environment monitoring device according to the present invention has a test piece 1 having a plurality of gaps 2 of several hundreds of μm arranged in parallel with each other.
And a support plate 3 attached to both sides of the test piece 1 in parallel with the gap portion 2, a foil stretched straight between the support plates 3 and a strain gauge 5 attached to the surface of the foil 4. Corrosion preferentially progresses in the gap portion 2 as compared with the free surface 6, and a corrosion product 7 is generated, which serves as a force 8 for pushing and expanding the gap 2.
This force 8 gives tension to the foil 3, and its magnitude can be measured with a strain gauge 4 attached to the surface as a strain amount with a resolution of 1 × 10 ⁻⁶ .

Further, it is also possible to measure the stress change due to the increase in volume of the test piece 1 caused by corrosion by the piezoelectric element 21 as shown in FIG. In this case, the piezoelectric element 21 is arranged in contact with one side of the test piece 1 via the insulating film 22, and the piezoelectric element 21 and the test piece 1 are fixed by the support 23 having high rigidity. The force 8 associated with the increase in volume due to the formation of the corrosion product 7 in the gap 2 gives a compressive stress to the piezoelectric element 21 and its magnitude can be measured with a resolution of nV (nanovolt) as a change in the voltage applied to the piezoelectric element 21. .

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 3 is a configuration diagram of a corrosive environment monitoring device according to an embodiment of the present invention. The case where the strain gauge 5 is used is shown. The strain caused by the stress caused by the corrosion of the test piece 1 shown in FIG. 1 becomes the resistance change of the strain gauge 5, and the resistance change is changed as a voltage change by the signal conditioner 31. It is converted and amplified, and is input to the computer 33 as the distortion amount of the test piece 1 via the A / D converter 32. The obtained strain amount is displayed or displayed on the CRT screen and is based on a calibration curve indicating the relationship between the strain amount and the corrosion amount that has been previously obtained,
It is converted into the amount of corrosion by the computer 33. The data thus obtained is stored and recorded in the external storage device 34 and the external recording device 35 connected to the computer 33.

FIG. 4 shows the structure of a test piece in which the structure of the clearance is facilitated. The test piece consists of a single spiral coil 41, which is compressed into the support 23 to form a coil.
Since a plurality of gaps are formed in 41, the processing cost of the test piece can be greatly reduced.

FIG. 5 shows a test piece in which the gap portion is formed by using the spiral coil 51, and a large number of gaps can be formed at the same time by compressing it in the support member 23.

FIG. 6 shows the structure of a comb-teeth test piece 61 in which the structure of the gap portion is formed by making a notch in the test piece. The comb test 61 has an advantage that it is easy to support and can be easily manufactured from the same material as that actually used.

FIG. 7 shows a test piece obtained by folding the foil 71 in the structure of the clearance, which also has an advantage that it can be easily supported.

FIG. 8 shows a test piece having the structure of the crevice part by inserting another member 81 for accelerating corrosion into the test piece 1 having a wide crevice width. Other components that accelerate corrosion here 81
Is different depending on the type of material of the test piece 1, but a material having a higher electrochemical potential than the test piece 1 is generally used. Graphite, platinum and gold are particularly effective. Insulators can also be used, and plastics such as polycarbonate and Teflon and rubber such as neoprene are effective.
Further, it is also effective to form another member having the same shape as the test piece and insert the concave and convex portions into each other to form an acceleration gap, instead of individually inserting other members into the gap.

FIG. 9 shows an outline of strain measurement. In this case, the thin plate 91 used for strain measurement is attached to the head of an L-shaped and highly rigid support body, and the thin plate 91 and the support body 23 are U-shaped. The test piece 1 having the gap portion 2 is sandwiched between one side of the support 23 and the thin plate 91 and fixed so as to crush the gap portion 2. Therefore, a bending stress is applied to the thin plate 91. The strain gauge 5 is attached to the surface of the thin plate 91 with an adhesive 92. The strain gauge 5 is selected in consideration of waterproofness and heat resistance according to the corrosive environment in which it is installed. When waterproofing is required at high temperatures, a welding gauge with a gauge embedded in a metal tube is effective. Also, if necessary, the thin plate may be replaced with a diaphragm to isolate the strain gauge from the corrosive environment.

FIG. 10 shows the structure of a stress measuring element utilizing the piezoresistive effect. The piezoresistive effect is a phenomenon in which the electrical conductivity changes and the specific resistance changes when an external force acts on the crystal. The silicon element 101 has an N-type diffusion resistance layer 102 and a P-type diffusion resistance layer 10
3 is formed, and the resistance change due to the stress is taken out as a voltage through the lead wire 104. Since the piezoresistive coefficient depends on the crystal direction, multiaxial stress components can be taken out by forming a diffusion resistance layer by changing the crystal direction using single crystal silicon. FIG. 10 is arranged so that the three-direction stress components can be detected separately. Five rectangular resistors having a width of 10 μm and a length of 300 μm are arranged in series. Further, since the diffusion resistance has a strong temperature dependency, the temperature measuring element 105 is embedded in the silicon element 101. This stress measuring element is extremely small, and its waterproof shield can be easily and reliably provided by using semiconductor packaging.

Also, when the corrosive environment is severe, a device having the configuration shown in FIG. 11 has been devised as a method for avoiding deterioration of the measuring means.
Here, the stress measuring element 111 is isolated from the corrosive environment 112 in which the test piece 1 is arranged by the seal diaphragm 113.
The stress measuring element 111 is held in a sealing liquid 114 for force transmission. Lead wire 1 through hermetic seal 115
04 is taken out and connected to the amplifier 116.

To measure such a voltage change, a method to directly capture the stress change as a DC voltage change and a method to superimpose a small amplitude sine wave and use lock-in to extract only the signal synchronized with that frequency to lower the noise level Is also effective.

FIG. 12 is a block diagram of an apparatus for measuring the mass increase due to corrosion in the gap. The figure shows the case of using the crystal unit 201, which is a thin film of the material to be monitored for corrosion.
2 is deposited on the crystal unit 201, and the thin film 202 forms a gap with the holder 203 of the crystal unit 201. When the thin film 202 corrodes in this gap and the mass of the corrosion product increases, the resonance frequency of the crystal unit 201 decreases.
The magnitude of this drop is proportional to the mass change. Using a 6MHz oscillator, a change of 1Hz corresponds to a mass change of 1.23 × 10 ^-8 g / cm ² and is extremely sensitive.

In FIG. 12, 204A and 204B are crystal oscillators, 205A and 205B are mixers, 206 is a bandpass filter, and 207 is 400 to 500.
A KHz oscillator, 208 is a roll pass filter, 209 is an amplifier, 32 is an A / D converter, 33 is a computer, 34 is an external storage device, and 35 is an external recording device. In the above configuration,
The signal from the crystal oscillator 204A is input to the mixer 205A, and the standard signal from the crystal oscillator 204B, that is, the standard signal lower than the crystal oscillator 204A by 0.5 KHz is a signal from the oscillator 207 whose frequency is variable (400-500 KHz). And mixer 205B
, And the sum and difference frequencies of both frequencies are obtained. These signals are sent to the bandpass filter 206, of which only the sum of the frequencies passes through the bandpass filter 106 and is input to the mixer 205A. Mixer 2
In 05A, the standard signal and the measurement signal are mixed to form a beat, and the signal is input to the amplifier 209 via the roll pass filter 208. The amplifier 209 amplifies the input signal and outputs the amplified signal to the computer 33 via the A / D converter 32. Computer 32 calculates the change in mass
It is displayed on the CRT and stored and recorded in the external storage device 34 and the external recording device 35.

For the crystal unit used for measurement, AT-cut crystal whose resonance frequency is extremely stable against temperature is most desirable. In addition, the resonance frequency is more advantageous from the viewpoint of sensitivity, but it is 6-10KHz considering the stability of oscillation and the ease of handling.
Is desirable.

FIG. 13 is a structural diagram of a crystal unit in which thin films, which are targets of corrosion monitoring, are laminated. The crystal unit 201 has a chromium film 141 vapor-deposited on both sides to improve adhesion, and a target thin film 202 is vapor-deposited thereon.

A gap forming member 142 made of a foil of a material electrochemically more noble than the thin film 202 is stacked on the thin film 202 on the crystal unit 201 to form a gap, and the gap is held by a holder 203. It is also effective to vapor-deposit gold or silver on the chromium film 141 to form an electrode in order to ensure electrical connection. It is also effective to use the gap forming material 142 as a plastic film or rubber which is an insulator.

FIG. 14 shows the case where the gap constituent material is fine particles.The fine particles 151 scattered on the thin film 202 deposited through the chromium film on the surface of the crystal unit 201 have the fine particles 151 scattered on the contact surface with the thin film 202. Make up the department. As fine particles, graphite powder is desirable.

Since graphite has a very high potential electrochemically,
It is very effective as a crevice component that accelerates corrosion,
It can be used in the form of fiber, wool or gasket.

Whether a strain gauge or a piezoelectric element is used as the measuring means or a crystal oscillator is used as the measuring means, it is necessary to compensate for an error due to temperature change in order to perform accurate measurement. for that purpose,
It is effective to attach a strain gauge to a highly rigid support part and obtain a difference from the strain gauge for measurement, or to arrange a quartz oscillator laminated with thin films that do not cause corrosion.

FIG. 15 shows an embodiment in which the corrosive environment monitoring device according to the present invention is applied to monitor the water quality of reactor water in a reactor pressure vessel. In a reactor pressure vessel 161, a corrosion environment monitoring device including a stainless steel test piece 1 forming a gap and a high temperature waterproof welding strain gauge is arranged. Its location is near the structure inside the reactor, for example, the control rod 16 installed in the core.
Water supply sparger 165 installed between 3 and above the core
At or near the CRD 168 in the lower core, or in or near the pipe 167, the valve 169, the pump 170 in the recirculation system extending from the lower core to the outside of the reactor pressure vessel 161, and the recirculation. The outlet is a jet pump 166 for sending the reactor water 162 returned from the system to the lower part of the core. Reactor water 162
The deterioration of the water quality of No. 1 promotes the corrosion of the crevice and brings about an increase in the amount of strain, so that it can be easily monitored by this example.

FIG. 16 shows a histogram in which a large number of corrosive environment monitoring devices according to the present invention are arranged in a nuclear power plant as shown in FIG. 15, and measured values obtained from these devices are compared with plant drawings on a CRT screen of a computer. Displayed at 171, it is possible to determine in which part of the plant the water quality abnormality has occurred.

Fig. 17 shows the flow for finding out the abnormal value by evaluating the statistical distribution of the measured values obtained from the corrosive environment monitoring devices arranged in the atomic plant, depending on the size of the measured value. Create a histogram and set the cumulative distribution F to F =
Calculation is performed based on N / N + 1 (N is the number of data points), normal probability plotting is performed, the fit of the linear approximation is examined, and if the fit is good, the normal distribution parameter is determined, and the average value and standard deviation are calculated. When the conformity is bad, it is examined whether the data is an abnormal value, and if it is determined to be an abnormal value, an alarm is issued.
And we will pursue the cause.

Figure 18 is a plot of the normal probabilities of the measured values obtained by the corrosive environment monitoring device using the array method. The horizontal axis of the graph shows the corrosiveness of the water quality to be monitored, and the vertical axis shows the cumulative probability F. The average value and standard deviation are obtained from the parameters of the normal distribution of the measured values, which improves the reproducibility of the measurement and enables highly reliable monitoring.

FIG. 19 shows an embodiment in which the apparatus of the present invention monitors the corrosiveness of air circulating between large-capacity magnetic disk storage devices. When the storage medium 191 rotates in the direction of arrow A, the air flows circumferentially along the storage medium 191 in the direction of rotation in the direction of arrow B, but a part of the air positions the head arm assembly for access 193 that positions the head. Flow into the storage medium 191 again via the filter 194 for removing dust particles. Here, the corrosive environment monitoring device 195 according to the present invention is a bearing that supports the head 196 and the load arm 197 to monitor the corrosion degree of the storage medium 191 and the corrosiveness of the circulating air.
It is provided on the upstream side of 192 and close to the storage medium 191. The signal from the corrosive environment monitor is displayed on the CRT screen by the computer.

FIG. 20 shows an embodiment in which the corrosive environment monitoring device according to the present invention is used to monitor the water quality of water used for cooling the elements of a large computer. This is a cooling water circulating device for cooling the element 211 installed in the processor unit 216 of the large computer, and the corrosive environment monitoring device 1 is installed in the tank 212.
95 are arranged. The cooling water in the tank 212 on the side of the cooling water supply control unit 217 is heated by the pump 215 in the heat exchanger 213
To the processor section 216 to cool the element 211 and return to the tank 212 again. The corrosive environment monitor 195 monitors the corrosiveness of this cooling water.

As described above, according to each of the corrosive environment monitoring devices described above, each corrosive environment monitoring device has a test piece having a gap portion, and since the corrosion is accelerated in the gap portion, the response to corrosion is fast and high. Corrosive environment can be detected with sensitivity.

Also, the test piece can be manufactured at low cost by using a single member such as a spiral coil (see FIG. 4), a spiral coil (see FIG. 5), and a folded foil (see FIG. 7). be able to.

In addition, a corrosion environment monitoring device that detects the corrosion product generated in the gap of the test piece as the mass change of the test piece (No. 13
By using Fig. 14 and Fig. 14), it becomes possible to detect local corrosion of the structure, for example, pitting corrosion.

In addition, in the case of a test piece with a gap, even if the material of the test piece is corrosion-resistant stainless steel, aluminum alloy, copper alloy, nickel-based alloy, oxygen is deficient in the gap and the oxide film is maintained. Since it is not possible and the corrosion proceeds, it is possible to easily detect the corrosion of the steel or alloy structure.

The corrosive environment monitoring device according to the present invention can be used in any environment such as high temperature, high pressure, water, and the atmosphere if the measuring means is cut off from the corrosive environment (see FIG. 11), the plant,
The reliability of equipment maintenance can be improved.

〔The invention's effect〕

According to the present invention, a corrosive environment monitoring method and its device,
Since it was decided to measure the stress change or mass change of the member caused by the corrosion product generated in the gap formed in the member, the corrosion in the gap progresses much more accelerated than at the free surface, The response is fast and the corrosion can be detected with high sensitivity.In addition, if the member is made of a corrosion resistant material, oxygen will be deficient in the gap, so the oxide film cannot be maintained and corrosion Therefore, it becomes possible to easily detect the corrosion of the structure of the corrosion resistant material.

Furthermore, by using a corrosion environment monitoring device that detects a corrosion product generated in a gap portion of a member as a mass change of the member, it becomes possible to detect local corrosion of the structure, for example, pitting corrosion.

In addition, the members that make up the gap are spiral coils,
It can be manufactured at low cost by using a single member such as a spiral coil or a folded foil.

[Brief description of the drawings]

FIG. 1 shows an example of the operating principle of the method of the present invention, FIG. 2 shows another example of the operating principle of the method of the present invention, and FIG. 3 shows an example of an apparatus for carrying out the method of the present invention. Block diagram, 4th,
5, 6, 7, and 8 are diagrams showing examples of test pieces for carrying out the method of the present invention (measurement of stress change), and FIGS. 9, 10, 11 are measuring means for carrying out the method of the present invention. Fig. 12 is a block diagram showing an example of an apparatus for carrying out the method of the present invention, and Figs. 13 and 14 are examples of test pieces for carrying out the method of the present invention (measurement of mass change). Structural diagram showing the first
FIG. 15 is a schematic sectional view showing an example of implementing the apparatus of the present invention for monitoring reactor water water quality in a reactor pressure vessel, FIG. 16 is a map showing measured values as a display example, and FIG. 17 is an example of the present invention. Such a flow chart, FIG. 18 is a diagram showing an example in which measured values are represented by probability plots, and FIG. 19 is a diagram showing an example in which the device according to the present invention is applied to a cooling system of a large-capacity magnetic disk storage device. FIG. 20 is a diagram showing an example in which the device according to the present invention is applied to a cooling system of a large computer. 1 ... Test piece, 2 ... Gap, 5 ... Strain gauge, 21 ...
… Piezoelectric element, 111 …… Stress measuring element, 201 …… Crystal resonator.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunio Hasegawa 502 Jinritsucho, Tsuchiura-shi, Ibaraki Machinery Research Laboratory, Hitachi, Ltd. (56) Reference JP-A-54-106796 (JP, A) JP-A-2- 195227 (JP, A)

Claims (24)

(57) [Claims] 1. A method for monitoring a corrosive environment in which a stress change in a member due to an increase in volume due to a corrosion product generated in a gap formed in the member is measured. 2. A corrosive environment monitoring device comprising: a member that constitutes a gap portion; and a measuring means that responds to a stress change of the member due to a volume increase due to a corrosion product generated in the gap portion. 3. The corrosive environment monitoring device according to claim 2, wherein the member forming the gap portion is formed of a compressed spiral coil. 4. The corrosive environment monitoring device according to claim 2, wherein the member forming the gap portion is formed of a compressed spiral coil. 5. The corrosive environment monitoring device according to claim 2, wherein the member forming the gap portion is formed of comb teeth. 6. The corrosive environment monitoring device according to claim 2, wherein the member forming the gap is formed by folding a foil. 7. The corrosive environment monitoring device according to claim 2, wherein the member forming the gap portion is formed by inserting another member that accelerates corrosion into a gap formed in a certain member. 8. The corrosive environment monitoring device according to claim 2, wherein said measuring means comprises an electromechanical load converter. 9. The corrosive environment monitoring device according to claim 2, wherein said measuring means comprises a piezoelectric transducer. 10. A corrosive environment monitoring method for measuring a mass change of a member due to a corrosion product formed in a gap formed in the member. 11. A corrosive environment monitoring device comprising: a member that constitutes a gap portion; and a measuring means that responds to a change in mass of the member due to a corrosion product generated in the gap portion. 12. The corrosive environment monitoring device according to claim 11, wherein the measuring means comprises a crystal oscillator. 13. The corrosive environment monitoring device according to claim 11, wherein the member forming the gap is composed of a thin film laminated on the crystal unit and another member in contact with the thin film. 14. The member constituting the gap portion is composed of a thin film laminated on a crystal unit and another member which is in contact with the thin film and is electrochemically noble than the thin film. 11. Corrosion environment monitoring device described in 11. 15. The corrosive environment monitoring device according to claim 11, wherein the member forming the gap is composed of fine particles and another member in contact with the fine particles. 16. The corrosive environment monitoring device according to claim 11, wherein the member forming the gap is composed of fine particles made of graphite as a corrosion accelerator and other members in contact with the fine particles. . 17. The member forming the gap is composed of a fiber, wool or gasket based on graphite as a corrosion accelerator, and another member in contact with the fiber, wool or gasket. 12. The corrosive environment monitoring device according to claim 11. 18. A temperature sensor for temperature compensating a value measured by the measuring means.
Or the corrosive environment monitoring device described in 11. 19. Any one of claims 2 to 9 and 11 to 17
Measure the corrosion of water using the corrosive environment monitoring device described in the item,
A water quality monitoring system characterized by detecting deterioration of water quality from the degree of corrosion progress of the water. 20. Any one of claims 2 to 9 and 11 to 17
A plurality of corrosive environment monitoring device according to the paragraph is arranged in the plant, and the measured value obtained by the corrosive environment monitoring device is displayed in correspondence with the drawing of the plant drawn on the CRT screen. Characteristic plant water quality monitoring system. 21. The water quality monitoring system for a plant according to claim 20, wherein a statistical distribution of the measured values is evaluated and an abnormal value of the measured values is detected. 22. Any one of claims 2 to 9 and 11 to 17
A more corrosive environment monitoring method, characterized in that a large number of corrosive environment monitoring devices according to the item (1) are arranged in an array, and the measured values obtained from the corrosive environment monitoring devices are statistically processed. 23. Any one of claims 2 to 9 and 11 to 17
Measures the corrosiveness of the installation environment using the corrosive environment monitoring device described in the paragraph, and gives an alarm when the measured corrosiveness reaches a predetermined value.
A large-capacity magnetic storage device having a monitor device for displaying on a CRT. 24. Any one of claims 2 to 9 and 11 to 17
Using the corrosive environment monitoring device described in the paragraph, the corrosiveness of the cooling medium for cooling the internal element is detected, and a monitor device is provided for displaying an alarm on the CRT when the measured corrosiveness value reaches a predetermined value. A computer device characterized by the above.