JP7656795B2 - Characteristics Test Equipment - Google Patents

Description

The present invention relates to a characteristic testing apparatus capable of evaluating material characteristics in a specified environment, such as a hydrogen atmosphere.

Patent Document 1 below discloses a characteristic testing device for evaluating the characteristics or durability of a flat test piece in a fluid atmosphere such as a hydrogen atmosphere. This characteristic testing device includes a container that is partitioned into a first space and a second space by the test piece and that contains the test piece, and supplies a first fluid (e.g., hydrogen gas) whose pressure is varied by a fluid pressure adjusting means to the first space to apply a repeatedly varying bending load to the test piece, and supplies a second fluid (e.g., argon gas) to the second space, and analyzes the amount of cross-leak of the first fluid into the second space as damage to the test piece progresses as a change over time in the concentration of the first fluid contained in the second fluid.

Patent Publication 2018-0597239

However, in the conventional characteristic testing device of Patent Document 1, as damage to the test piece progresses, the first fluid in the first space and the second fluid in the second space begin to diffuse into each other, making it impossible to maintain the balance of pressure between the two fluids. This poses the problem that a back pressure valve must be provided in the exhaust system for the second fluid and the back pressure valve must be manually throttled to balance the pressures.

The present invention has been made in view of the above problems, and a main object of the present invention is to provide a characteristic testing device that can automatically maintain a balance between the pressure of the first fluid in the first space and the pressure of the second fluid in the second space, even if damage to the test piece progresses in the characteristic testing device of Patent Document 1, until the test piece approaches or even breaks.

In order to achieve the above-mentioned object, the characteristic testing apparatus according to the present invention is a characteristic testing apparatus for evaluating the mechanical characteristics, creep characteristics, fatigue characteristics, etc. of a test piece in an atmosphere of a fluid such as hydrogen, and is characterized by comprising: a container for storing the test piece, the container being partitioned into a first working space and a second working space, each having a fixed volume by the test piece, a first fluid supplying means for supplying a first fluid to the first working space formed between the container and the stored test piece, a first fluid pressure adjusting means for adjusting the pressure of the first fluid supplied to the first working space to apply a repeatedly fluctuating bending load to the test piece, a first fluid flow measuring means for measuring the flow rate of the first fluid supplied to the first working space, a second fluid supplying means for supplying a second fluid to the second working space formed between the container and the stored test piece, a second fluid pressure adjusting means for adjusting the pressure of the second fluid supplied to the second working space, and a calculation means for continuously calculating the pressure of the second fluid pressure adjusting means based on flow rate measurement data of the first fluid measured by the first fluid flow measuring means.

In addition, the characteristic testing device of the present invention is a characteristic testing device for evaluating the mechanical properties, creep properties, fatigue properties, etc. of a test piece in an atmosphere of a fluid such as hydrogen, and is characterized by comprising a second fluid supply means for supplying a second fluid different from the first fluid in the first operational space to the second operational space, and a concentration analysis means for analyzing the change over time in the concentration of the first fluid contained in the second fluid that cross-leaks into the second operational space due to damage to the test piece.

Furthermore, the characteristic testing apparatus of the present invention is characterized in that, in the characteristic testing apparatus described in claims 1 and 2, it is equipped with a circulation system for forming a loop of the second fluid and circulating the second fluid within the loop, a circulation means as a power source for circulating the second fluid, and a concentration analysis means.

According to the characteristic testing device of the present invention, the pressure waveform programmed by the first calculation means is transmitted to the first pressure fluctuation valve via the first pressure adjustment means, and the pressure of the first fluid is fluctuated to apply a repeatedly fluctuating bending load to the test piece stored in the container, thereby achieving a compact structure and achieving the effect of reducing fluid leakage outside the device.

Furthermore, according to the characteristic testing device of the present invention, even if interdiffusion occurs between the first fluid in the first working space and the second fluid in the second working space as damage to the test piece progresses and the pressure equilibrium between the first and second fluids changes over time, the change over time in the flow rate of the first fluid supplied to the first working space is measured by the first fluid flow rate measuring means, the flow rate data is input to the second calculation means, the set pressure of the second fluid pressure regulating means is calculated, and the opening of the second pressure fluctuation valve is predicted, thereby achieving the effect of automatically and continuously setting the pressure of the first fluid and the pressure of the second fluid to a new equilibrium state.

In addition, the characteristic testing device according to the present invention has the advantage that the progression of damage to the test piece, i.e., the change over time in the degree of damage to the test piece, can be quantified based on the change over time in the pressure of the second fluid continuously calculated by the second calculation means.

In addition, according to the characteristic testing device of the present invention, by incorporating polynomial approximation and even deep learning functions of artificial intelligence into the second calculation means, it is possible to construct a database for test pieces made of various types of materials.

In addition, according to the characteristic testing device of the present invention, in addition to the effects achieved by the characteristic testing device described in claim 1, since it is equipped with a concentration analysis means, it has the effect of being able to grasp the temporal change in the degree of damage to the test piece caused by the bending load by analyzing the change over time in the concentration of the fluid contained in the second action space.

In addition, according to the characteristic testing device of the present invention, by combining the progression of damage to the test piece inferred from the temporal change in the equilibrium state between the pressure of the first fluid and the pressure of the second fluid calculated by the second calculation means, and the progression of damage to the test piece inferred from the temporal change in the concentration of the first fluid in the second fluid in the second action space from the concentration analysis means, it is possible to achieve the effect of grasping the progression of damage to the test piece in a more three-dimensional manner.

Furthermore, according to the characteristic testing device of the present invention, in addition to the effects achieved by the characteristic testing device described in claims 1 and 2, by being provided with a circulation system for circulating the second fluid, a circulation means as a power source for circulating the second fluid, and a concentration analysis means, the device has the effect of being able to detect even slight cross-leakage of the first fluid into the second space.

1 is a schematic diagram showing a first embodiment of a characteristic test device according to the present invention; 4 is a calculation result showing a pressure history of a first fluid and a pressure history of a second fluid in the first embodiment of the characteristic test device of the present invention. FIG. 2 is a schematic diagram showing a second embodiment of a characteristic test device according to the present invention. FIG. 11 is a schematic diagram showing a third embodiment of a characteristic test device according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

First embodiment

FIG. 1 is a schematic diagram showing a first embodiment of the characteristic test device of the present invention. The characteristic test device 1 of the first embodiment includes a container 3 in which a flat test piece 2 is stored. The container 3 includes a first working space 6 formed by the flat test piece 2 and a container upper part 5 having a generally inverted concave shape in vertical section, and a second working space 22 formed by a container lower part 21 having a generally concave shape in vertical section and the back surface of the flat test piece 2, which is located opposite the first working space 6 and separated from the first working space 6 across the flat test piece 2. The container 3, which forms the first working space 6 and the second working space 22 inside, is configured such that the container upper part 5 and the container lower part 21 are openable and closable. The container 3 includes a packing 4 made of metal or resin, and when the container upper part 5 and the container lower part 21 are closed, the lower end of the container upper part 5 and the upper end of the container lower part 21 are overlapped via the packing 4. This allows the container 3 to be sealed, and the first working space 6 and the second working space 22 sealed in the container 3 can be formed.

The vessel 3 in the first embodiment is made of metal containing at least one of iron, nickel, chromium, aluminum, and copper. The vessel upper portion 5 is cylindrical, disk-shaped, spherical, or rectangular with a bottom that opens downward, and the vessel lower portion 21 is cylindrical, disk-shaped, spherical, or rectangular with a bottom that opens upward.

In addition, the characteristic test apparatus 1 of this first embodiment is equipped with at least one fluid supply system, namely, a first fluid supply system 11 consisting of a gas cylinder 7 as a first fluid supply means for supplying a fluid to the first working space 6 to create a test environment, and a first fluid compressor 8 as a first pressurizing means for pressurizing the fluid supplied to the first working space 6, and a second fluid supply system 27 consisting of a gas cylinder 23 as a second fluid supply means for supplying a fluid to the second working space 22, and a second fluid compressor 24 as a second pressurizing means for pressurizing the fluid supplied to the second working space 22.

The first fluid supply system 11 is connected to the first working space 6 of the upper container 5. As a result, gas from the gas cylinder 7 is supplied to the first working space 6 of the upper container 5. In addition, the second fluid supply system 27 is connected to the second working space 22 of the lower container 21. As a result, gas from the gas cylinder 23 is supplied to the second working space 22 of the lower container 21. The first fluid supply means 7 or the second fluid supply means 23 may be configured to supply gas from the gas cylinder via a pressure reducing valve.

The first fluid compressor 8 and the second fluid compressor 24 compress gas from the gas cylinders 7, 23. When the first fluid supply system 11 is provided, a first fluid pressure gauge 9 for detecting the pressure of the first fluid compressor 8 or the fluid on the output side of the pressure reducing valve is provided in the first fluid supply system 11. When the second fluid supply system 27 is provided, a second fluid pressure gauge 25 for detecting the pressure of the second fluid compressor 24 or the output side of the pressure reducing valve is provided in the second fluid supply system 27. The first fluid compressor 8 and the second fluid compressor 24 are adjusted based on the detected pressures of the first fluid pressure gauge 9 and the second fluid pressure gauge 25.

The characteristic test device 1 of the first embodiment also includes at least one of a first fluid discharge system 14 or a first fluid valve discharge system 12 that discharges the fluid from the first working space 6 to the outside of the container 3, and at least one of a second fluid discharge system 30 or a second fluid valve discharge system 28 that discharges the fluid from the second working space 22 to the outside of the container 3. All of these fluid discharge systems are configured to retain fluid within the device, and the first fluid discharge system 14 may be provided with a first fluid discharge valve 15, and the second fluid discharge system 30 may be provided with a second fluid discharge valve 31.

Furthermore, the characteristic testing device 1 of this first embodiment is provided with a first working space pressure gauge 10 for detecting the pressure in the first working space 6 at least at one location of the first fluid valve outlet system 13 or the first working space 6 or the first fluid discharge system 14, and is provided with a first fluid pressure adjusting means 17 and a first fluid pressure fluctuation valve 16 for adjusting the pressure value of the first working space pressure gauge 10 to a predetermined pressure value or a predetermined pressure fluctuation range.

In addition, the characteristic test device 1 of this first embodiment is equipped with a first calculation means 18, and is configured to transmit the pressure waveform programmed in the first calculation means 18 as a signal to the first fluid pressure adjustment means 17, thereby driving the first fluid pressure fluctuation valve 16 to the programmed pressure waveform.

1, the first fluid pressure fluctuation valve 16 is provided in the first fluid supply system 11, but may be provided in the first fluid exhaust system 14. On the other hand, in FIG. 1, the second fluid pressure fluctuation valve 32 is provided in the second fluid supply system 27, but may be provided in the second fluid exhaust system 30.

Furthermore, the characteristic testing device 1 of the first embodiment is provided with a second working space pressure gauge 26 for detecting the pressure in the second working space 22 at least at one location of the second fluid valve outlet system 29 or the second working space 22 or the second fluid discharge system 30, and is provided with a second fluid pressure adjusting means 33 and a second fluid pressure fluctuation valve 32 capable of adjusting the pressure value of the second working space pressure gauge 26 to a predetermined pressure value or a predetermined pressure fluctuation range.

Furthermore, the characteristic test device 1 of this first embodiment is configured to incorporate a first fluid flow rate measuring means 19 in the first fluid supply system 11, and to transmit data on the flow rate of the first fluid recorded by the first fluid flow rate measuring means 19 to the second calculation means 34 via a first fluid measurement value transmitting means 20.

In FIG. 1, the first fluid flow rate measuring means 19 is incorporated in the first flow rate supply system 11, but it may be incorporated in the first fluid valve exhaust system 12 or the first fluid exhaust system .

In this first embodiment, the first fluid pressure fluctuation valve 16 and the second fluid pressure fluctuation valve 32 can be driven by air pressure in response to signals from the first fluid pressure adjustment means 17 and the second fluid pressure adjustment means 33 to set the valve opening degree, but the valve drive source can also be constituted by a motor (electric motor), an electromagnet (solenoid), a piezoelectric element (piezo stack), etc.

In FIG. 1, the first calculation means 18 and the second calculation means 34 each include a calculation circuit including, for example, a central processing unit (CPU), a programmable logic controller (PLC), and memory means (RAM and ROM).

In addition, in Figure 1, a signal input circuit 35 from the second fluid pressure gauge 25 to the control operation unit 36 is illustrated as an example, but in addition to the second fluid pressure gauge 25, the system may also be equipped with a signal input circuit 35 from input devices such as the first fluid pressure gauge 9, the first working space pressure gauge 10, the second working space pressure gauge 26, the first fluid pressure adjustment means 17, the second fluid pressure adjustment means 33, and the first fluid flow rate measurement means 19, as well as a control operation unit 36 that receives and controls operational inputs from the test implementer and a control operation display unit 38 that displays the status of these control operations.

In addition, in FIG. 1, a signal output circuit 37 from the control operation unit 36 to the second calculation means 34 is illustrated as an example, but the system may also be equipped with a signal output circuit 37 to output devices such as the first fluid compressor 8, the second fluid compressor 24, the first fluid discharge valve 15, the second fluid discharge valve 31, the first fluid pressure fluctuation valve 16, the first calculation means 18, the second fluid pressure fluctuation valve 32, and the second calculation means 34, as well as a control operation unit 36 that receives and controls operation inputs from the test implementer and a control operation display unit 38 that displays the status of these control operations.

Next, a test method using the characteristic test device 1 of the first embodiment will be described. First, the flat test piece 2 is placed on the upper end of the lower container part 21, and the lower end of the upper container part 5 is overlapped and sealed via the packing 4. This prevents leakage of fluid from the overlapping part between the upper end of the lower container part 21 and the lower end of the upper container part 5.

After the flat test piece 2 is accommodated, gas is supplied from the gas cylinder 7 to the first working space 6 of the container 3 via the first fluid supply system 11. Also, gas is supplied from the gas cylinder 23 to the second working space 22 of the container 3 via the second fluid supply system 27. The gas supplied to the first working space 6 and the second working space 22 are compressed by the first fluid compressor 8 and the second fluid compressor 24, respectively. At this time, the first fluid compressor 8 and the second fluid compressor 24 are controlled so as to maintain the detected pressures obtained from the first fluid pressure gauge 9 and the second fluid pressure gauge 25, respectively, constant. When the pressures of the gas cylinders 7 and 23 are high, it is also possible to use pressure reducing valves instead of the first fluid compressor 8 and the second fluid compressor 24.

During the test, the flat test piece 2 is sandwiched between the upper container part 5 and the lower container part 21, and is fixed in a state in which the first working space 6 and the second working space 22 are separated from each other. The gas pressure of the first working space 6 is applied to the upper surface of the flat test piece 2, and the gas pressure of the second working space 22 is applied to the lower surface of the flat test piece 2.

Then, the pressure value or pressure waveform programmed and input to the first calculation means 18, or the pressure or pressure waveform input by the tester, is transmitted to the first pressure adjustment means 17, and the opening of the first fluid pressure fluctuation valve 16 can be adjusted based on the transmitted data. Fig. 2 shows, as an example, an output result of a trapezoidal pressure fluctuation 41 between a first fluid maximum pressure 39 and a first fluid minimum pressure 40. In Fig. 2, the pressure fluctuation is illustrated by a trapezoidal wave as an example, but a triangular wave, a sine wave, or a rectangular wave can also be used.

Here, the period and waveform width of the pressure waveform can be set automatically, continuously, or randomly as necessary, by the first calculation means 18. As a result, a test can be performed to evaluate fatigue damage and fatigue fracture of the flat test piece 2 by fluctuations in the pressure difference between the first working space 6 and the second working space 22.

Furthermore, during the process of characteristic testing of the flat test piece 2 using the characteristic testing device 1, when damage to the flat test piece 2 progresses and cross leakage of the first fluid from the first action space 6 to the second action space 22 begins to increase, this increase can be detected as an increase in the flow rate of the first fluid per unit time by the first fluid flow rate measuring means 19.

2 shows an example in which the increase in the first fluid flow rate is captured as, for example, an integrated flow rate using an integrating flow meter as the first fluid flow rate measuring means _19. As the first fluid flow rate 42 consumed per cycle of the trapezoidal wave increases from _q1 to _qi to _qj , the number of cycles 44 required to reach a predetermined integrated flow rate Q43 decreases from _n1 to _nj .

Furthermore, data on the increase in the flow rate of the first fluid measured by the first fluid flow rate measuring means 19 can be transmitted to the second calculation means 34 via the first fluid flow rate measurement value transmitting means 20. The second calculation means 34, which has received the data from the first fluid flow rate measuring means 19, performs calculation based on the received data, and can adjust the opening of the second fluid pressure fluctuation valve 32 via the second fluid pressure adjusting means 33 based on the calculation result.

2 shows an example of a change in the pressure 45 of the second fluid in accordance with adjustment of the opening degree of the second fluid fluctuation valve 32. The second fluid pressure 45 changes in stages from P ₁ ² , ..., P _i ² , ..., P _j ² .

² ( _P12 , ^... , _Pi2 ..., _Pj2 ) indicates the time-dependent characteristics of damage/fracture of the flat test piece ^2. Generally, a stress intensity factor is used as an index representing the time-dependent characteristics of damage/fracture of a material, and the change in the second fluid pressure 45 in the first embodiment can be said to be an index equivalent to the stress intensity factor.

As described above, according to the characteristic testing device 1 of the first embodiment, even if interdiffusion occurs between the first fluid in the first space 6 and the second fluid in the second space 22 as the damage to the flat test piece 2 progresses and the equilibrium in the pressures of the first and second fluids changes over time, the change over time in the flow rate of the first fluid supplied to the first space 6 is measured by the first fluid flow rate measuring means 19, the flow rate data is input to the second calculation means 34, the set pressure of the second fluid pressure adjustment means 33 is calculated, and the aperture of the second pressure fluctuation valve 32 is predicted by the method shown as an example in Figure 2, so that it is possible to continue to set the pressure of the first fluid and the pressure of the second fluid to a new equilibrium state continuously or stepwise.

Furthermore, according to the characteristic testing device 1 of the first embodiment, by adjusting at least one of the first fluid pressure fluctuation valve 16 and the second fluid pressure fluctuation valve 32 using the first fluid pressure adjustment means 17 and/or the second fluid pressure adjustment means 33, it is possible to intermittently and continuously create a difference between the fluid pressure in the first space 6 and the fluid pressure in the second space 22, and to intermittently and continuously apply a bending load to the flat test piece 2.

That is, according to the characteristic test device 1 of the first embodiment, it is possible to apply a bending load to the flat test piece 2 by the pressure difference between the first space 6 and the second space 22 that form the atmosphere, rather than applying a load to the flat test piece 2 by a hydraulic pump or cylinder. With this configuration, it is possible to eliminate the sliding part between the rod that applied a load to the test piece by piston movement in the past and the stationary hydrogen environment container. This makes it possible to reduce gas leakage such as hydrogen to a negligible level, ensuring high safety.

Furthermore, according to the characteristic test device 1 of the first embodiment, mechanisms for applying load to the test piece, such as hydraulic pumps and cylinders, are not required, making it possible to create a very compact testing machine.

In the characteristic test device 1 of this first embodiment, by using a hydrogen gas cylinder for at least one of the gas cylinders 7, 23 and filling at least one of the first space 6 and the second space 22 with hydrogen gas, it is possible to evaluate the characteristics of the flat test piece 2 in a hydrogen gas environment.

In this way, when a characteristic testing device 1 for evaluating the mechanical properties, creep properties, fatigue properties, etc. of a flat test specimen 2 in a fluid atmosphere is provided with a container 3 for storing the flat test specimen 2, a fluid supply means 7 for supplying hydrogen gas to a first space 6 between the flat test specimen 2 stored in the container 3, a first fluid pressure adjustment means 17 for adjusting the pressure of the hydrogen gas supplied to the first space 6, and a first fluid pressure fluctuation valve 16 for controlling the first fluid pressure adjustment means 17 to apply a load to the flat test specimen 2, the characteristics of the flat test specimen 2 in a hydrogen gas environment can be evaluated using a compact device while preventing leakage of hydrogen gas.

In the characteristic test apparatus 1 of the first embodiment, the test piece is flat, but it is possible to perform characteristic tests on test pieces that are roughly flat, hemispherical, or the like.

In the first embodiment, gas is given as an example of the fluid to be supplied to the first space 6 and the second space 22, but the present invention is not limited thereto. For example, the fluid may be a substance in a liquid state or a substance in a gas state at the test temperature. Examples of substances in a liquid state at the test temperature include liquid water, alcohol, and oil. The fluid may be any of these. Examples of substances in a gas state at the test temperature include reducing gases such as hydrogen, inert gases such as nitrogen and argon, rare gas elements such as helium, air, oxygen, and water vapor. The fluid may be any of these, or a mixed gas of these.

In the first embodiment, the container 3 is configured with the upper container portion 5 having a generally inverted concave vertical cross section and the lower container portion 21 having a generally concave vertical cross section, but is not limited to this. The container 3 may have a working space between the container 3 and the test piece. The working space may have at least a fluid passage, and may be, for example, a container 3 having one or more concave grooves or a structure similar to a separator of a fuel cell.

1 illustrates the characteristic test device 1 having both the first fluid supply means 7 and the first fluid discharge system 14, and also having both the second fluid supply means 23 and the second fluid discharge system 30, but the present invention is not limited thereto. For example, the characteristic test device 1 may have the first fluid supply means 7 and the first fluid valve discharge system 12 or/and the first fluid discharge system 14, the first fluid supply means 7 and the first fluid valve discharge system 12 or/and the first fluid discharge system 14, and the second fluid supply means 23, the second fluid supply means 23 and the second fluid valve discharge system 28 or/and the second fluid discharge system 30, or the second fluid supply means 23 and the second fluid valve discharge system 28 or/and the second fluid discharge system 30, and the first fluid supply means 7.

In the above first embodiment, an example was given in which the first fluid pressure fluctuation valve 16 was used in the first fluid supply system 11 as the first fluid pressure adjustment means, but the first fluid pressure adjustment means may be any means that adjusts the pressure of the fluid in the first space 6, and is not limited to this in any way. For example, the first fluid pressure fluctuation valve 16 may be used in the first fluid discharge system 14. Similarly, an example was given in which the second fluid pressure fluctuation valve 32 was used in the second fluid supply system 27 as the second fluid pressure adjustment means, but the first fluid pressure adjustment means may be any means that adjusts the pressure of the fluid in the second space 22, and is not limited to this in any way. For example, the second fluid pressure fluctuation valve 32 may be used in the second fluid discharge system 30.

Second embodiment

The characteristic test apparatus of the second embodiment is for quantifying the damage/destruction characteristics and leakage characteristics of a test piece, and is applicable to various characteristic test apparatuses, not limited to the first embodiment. FIG. 3 is a schematic diagram showing the characteristic test apparatus of the second embodiment. The characteristic test apparatus 1 of the second embodiment is basically the same as the characteristic test apparatus 1 of the first embodiment. Therefore, the following description will focus on the differences between the two, and corresponding parts will be denoted by the same reference numerals. Also, description of matters common to both embodiments will be omitted.

The characteristic test device 1 of the second embodiment has a second fluid discharge system 30 that discharges a second fluid having a different composition from the first fluid in the first space 6 to the outside of the container, and a concentration analyzer 46 that analyzes the concentration of the fluid that has leaked from the first space 6 to the second space 22 and is contained in the second fluid discharged from the second space 22 to the outside of the container 3. The concentration analyzer 46 also has a data recording system 47 that records the measured concentration value. For this purpose, gas cylinders 7 and 23 are used that have different compositions.

The concentration analyzer 46 is provided in the second fluid discharge system 30 and includes a metal oxide semiconductor gas sensor as a detector and a column, which is a tube for separating the sample gas. The concentration analyzer 46 performs gas analysis using a gas chromatography technique, and separates gases by utilizing the difference in speed at which gas components pass through the column. Gas components are identified by the appearance time (retention time) of peaks in a chromatogram. By changing the column, various gas types can be handled.

The data recording system 47 is a personal computer with dedicated software. For example, the sample name, measurement time, measurement temperature, etc. are input by operating the operation section of the data recording system 47, and the measurement results are displayed on the screen output section of the data recording system 47 after the measurement. Furthermore, the measurement data is stored in the memory section of the data recording system 47, so that the data can be easily managed and searched.

Next, the operation of the characteristic test device 1 of the second embodiment will be described. After the flat test piece 2 is stored in the container 3, gas is supplied from the gas cylinders 7, 23 to the first space 6 and the second space 22 of the container 3 through the fluid supply systems 11, 27. In this case, the type of the fluid in the first space 6 and the second fluid in the second space 22 are different. For example, a hydrogen cylinder is used as the gas cylinder 7 to fill the first space 6 with hydrogen gas, and an argon cylinder is used as the gas cylinder 23 to fill the second space 22 with argon gas. When the pressure of the gas supplied to the first space 6 and the second space 22 is low, it is compressed by the compressors 8, 24. Conversely, when the pressure of the gas cylinders 7, 23 is high, a pressure reducing valve is used instead of the compressors 8, 24.

In this state, the pressure of the first fluid in the first space 6 is made continuously or intermittently higher than the pressure of the second fluid in the second space 22, and the concentration of the first fluid leaked from the first space 6 to the second space 22 contained in the second fluid discharged from the second space 22 is analyzed by a concentration analyzer 46, making it possible to measure the gas permeability characteristics of the flat test piece 2, for example, the gas diffusion coefficient of Fick's law.

More specifically, in the case of the second embodiment, the concentration of the gas in the second fluid discharge system 30 is analyzed by the concentration analyzer 46, so that the concentration of hydrogen leaked into the argon can be measured.

According to the characteristic testing device 1 of the second embodiment, by changing the type of fluid in the first space 6 and the type of second fluid in the second space 22, applying a static bending load or a variable bending load to the flat test piece 2, and analyzing the concentration of the fluid that has leaked from the first space 6 to the second space 22 contained in the second fluid discharged from the second space 22, it is possible to continuously track the degree of damage to the flat test piece 2 caused by the bending load and the change in the damage over time.

Furthermore, according to the characteristic test device 1 of the second embodiment, even if interdiffusion occurs between the first fluid in the first space 6 and the second fluid in the second space 22 as the damage to the flat test piece 2 progresses and the equilibrium pressure of the first and second fluids changes over time, the change over time in the flow rate of the first fluid supplied to the first space 6 can be measured by the first fluid flow rate measuring means 19, the flow rate data can be input to the second calculation means 34, the set pressure of the second fluid pressure adjustment means 33 can be calculated, and the aperture of the second pressure fluctuation valve 32 can be predicted by the method shown as an example in Figure 2, thereby continuously setting the pressure of the first fluid and the pressure of the second fluid to a new equilibrium state.

Furthermore, according to the characteristic test device 1 of the second embodiment, by differentiating the types of fluid in the first space 6 and the second fluid in the second space 22, making the pressure of the fluid in the first space 6 higher than the pressure of the second fluid in the second space 22, and analyzing the concentration of the fluid that has leaked from the first space 6 to the second space 22 contained in the second fluid discharged from the second space 22, it is possible to identify the fluid permeability of the flat test piece 2, in particular the diffusion coefficient of the fluid.

Furthermore, by operating the first fluid pressure fluctuation valve 16 by the first fluid pressure adjustment means 17 upon receiving a signal from the first calculation means 18 as pressure control means, it is possible to apply pressure fluctuations 41, such as trapezoidal waves, rectangular waves, triangular waves, sine waves, etc., to the fluid in the first space 6 as a bending load mode to the flat test piece 2. In this case, by analyzing the concentration of the fluid leaked from the first space 6 to the second space 22 contained in the second fluid discharged from the second space 22 by the concentration analyzer 46, it is possible to quantitatively grasp the time-dependent characteristics of damage to the flat test piece 2 caused by the fluctuating load. Furthermore, since a data recording system 47 is provided, it is possible to record the data.

In this way, instead of applying a load to the flat test piece 2 using a hydraulic pump or a hydraulic cylinder, it is possible to apply a bending load to the flat test piece 2 using the pressure difference between the first space 6 and the second space 22 that form the atmosphere of the flat test piece 2. This configuration makes it possible to eliminate the sliding part between the rod that previously applied a load to the test piece using hydraulic piston movement and the stationary hydrogen environment container, thereby reducing gas leaks such as hydrogen to a negligible level and ensuring high safety. In addition, mechanisms that applied a load to the test piece, such as a hydraulic pump or a hydraulic cylinder, are no longer necessary, making it possible to create a very compact testing machine.

In particular, in the characteristic test device 1 of the second embodiment, for example, a hydrogen gas cylinder is used as the first fluid supply means 7 to circulate hydrogen gas in the first space 6, and an argon gas cylinder is used as the second fluid supply means 23 to circulate argon gas in the second space 22. In this state, the concentration analyzer 46 is used as a hydrogen gas analyzer to measure the concentration of hydrogen gas leaking from the first space 6 into the argon gas in the second space 22, thereby making it possible to measure the hydrogen gas permeability characteristic of the flat test piece 2, for example, the hydrogen gas diffusion coefficient. It is also possible to evaluate the time-dependent damage characteristic of the flat test piece 2 under variable bending load.

In the characteristic test device 1 of the second embodiment, the fluid in the first space 6 and the second fluid may be different fluids, and the fluid in the first space 6 and the second fluid may be, for example, a substance in a liquid state or a substance in a gaseous state at the test temperature. The substance in a liquid state at the test temperature may be liquid water, alcohol, or oil. The substance in a gaseous state at the test temperature may be hydrogen, nitrogen, air, oxygen, argon, helium, water vapor, or the like.

In the second embodiment, a gas analyzer is used as an example of the concentration analyzer 46, but the present invention is not limited to this. For example, the concentration analyzer 46 may be a liquid analyzer, an oxygen concentration meter, a mass spectrometer, a trace concentration gas analyzer, an oxygen analyzer conforming to the JIS standard, or the like.

3 illustrates the characteristic test device 1 including the first fluid supply means 7, the first fluid pressure fluctuation valve 16, the first fluid discharge system 14, the second fluid supply means 23, the second fluid pressure fluctuation valve 32, the second fluid discharge system 30, the concentration analyzer 46, and the data recording system 47, but the present invention is not limited to this. For example, the characteristic test device 1 may include the first fluid supply means 7, the first fluid pressure fluctuation valve 16, the first fluid valve discharge system 12 and/or the first fluid discharge system 14, the concentration analyzer 46, and the data recording system 47. Alternatively, the characteristic test device 1 may include the first fluid supply means 7, the first fluid pressure fluctuation valve 16, the first fluid valve discharge system 12 and/or the first fluid discharge system 14, the second fluid supply means 23, the concentration analyzer 46, and the data recording system 47.

Third embodiment

The characteristic test device of the third embodiment is for quantifying the damage/destruction characteristics and leakage characteristics of a test piece with high accuracy, and can be applied to various devices, not limited to the first and second embodiments. FIG. 4 is a schematic diagram showing the characteristic test device of the third embodiment. The characteristic test device 1 of the third embodiment is basically the same as the characteristic test device 1 of the first and second embodiments. Therefore, the following description will focus on the differences between the two, and corresponding parts will be denoted by the same reference numerals. Also, description of the matters common to the first and second embodiments will be omitted.

The characteristic test device 1 of the third embodiment has a second fluid discharge system 30 that discharges the second fluid, which has a different composition from the fluid in the first space 6, to the outside of the container, and is configured to return at least a portion of the second fluid discharged via the second fluid discharge system 30 to the second fluid supply system 27 via a second fluid circulation system 48, in which at least a concentration analyzer 46 and a second fluid circulation pump 49 are incorporated. The concentration analyzer 46 also has a data recording system 47 that records the measured concentration values.

Furthermore, a pressure reducing valve 50 may be incorporated in the second fluid circulation system 48 of the characteristic test device 1 of the third embodiment.

Next, the operation of the characteristic test device 1 of the third embodiment will be described. After the flat test piece 2 is stored in the container 3, gas is supplied from the gas cylinders 7, 23 to the first space 6 and the second space 22 of the container 3 through the fluid supply systems 11, 27. In this case, the type of the first fluid in the first space 6 and the second fluid in the second space 22 are different. For example, a hydrogen cylinder is used as the gas cylinder 7 to fill the first space 6 with hydrogen gas, and an argon cylinder is used as the gas cylinder 23 to fill the second space 22 with argon gas. When the pressure of the gas supplied to the first space 6 and the second space 22 is low, it is compressed by the compressors 8, 24. Conversely, when the pressure of the gas cylinders 7, 23 is high, a pressure reducing valve is used instead of the compressors 8, 24.

In this state, the pressure of the first fluid in the first space 6 is made continuously or intermittently higher than the pressure of the second fluid in the second space 22, and the concentration of the first fluid contained in the second fluid discharged from the second space 22 and leaking from the first space 6 to the second space 22 through the flat test piece 2 is analyzed by a concentration analyzer 46 provided in a second fluid circulation system 48 branched off from the second fluid discharge system 30, making it possible to measure the gas permeability characteristics of the flat test piece 2 and the breakage/destruction characteristics of the flat test piece 2 continuously, over a wide range, and with high precision.

To quantitatively explain the principle of the high measurement range of the characteristic test apparatus 1 of the third embodiment, for example, even if the upper measurement limit of the concentration analyzer 46 is in the range of 10 ppm, if the circulating flow rate of the second fluid is 10 and the leakage amount of the first fluid into the second fluid through the flat test piece 2 is 1, then in practice it is possible to measure in the range of 100 ppm. In this case, the circulating flow rate of the second fluid circulating system 48 can be controlled and managed by the flow rate of the second fluid circulating pump 49.

Conversely, to quantitatively explain the principle of high measurement accuracy of the characteristic test device 1 of the third embodiment, for example, even if the lower measurement limit of the concentration analyzer 46 is 1 ppm, the circulation flow rate of the second fluid in the circulation system 48 is constant, whereas the first fluid leaking from the first space 6 to the second space 22 via the flat test piece 2 accumulates over time and the concentration of the first fluid in the second fluid increases, so that a leak concentration of 1 ppm or less, which is the lower measurement limit of the concentration analyzer 46, can be observed. In other words, it is possible to further increase the accuracy of the breakage and destruction characteristics of the flat test piece 2.

In addition, in the characteristic test device 1 of the third embodiment, by providing the circulation system pressure reducing valve 50 at any position in the second fluid circulation system 48, it is possible to reduce the fluid pressure downstream of the circulation system pressure reducing valve 50. By incorporating the concentration analyzer 46 downstream of the pressure reducing valve 50 in the circulation system 48 and upstream of the second fluid circulation return pump 49, it is possible to reduce the design pressure of the concentration analyzer 46.

The following technical ideas can be understood from the above embodiment.
(1) A characteristic testing device characterized in that a load is applied in at least one direction of the test piece by the fluid by varying the pressure difference between the internal pressure of a first space (the first working space) and the internal pressure of a second space (the second working space).

According to the invention of (1), a low-cost characteristic test device can be provided without requiring a large-scale and complicated structure.

The present invention is applied to a characteristic testing device for evaluating material characteristics such as gas permeability and fatigue characteristics of a test specimen exposed to a hydrogen environment.

1. Characteristic test device 2. Flat test piece (test piece)
3 Container 4 Packing 5 Container upper part 6 First working space (first space)
7 First fluid supply means (gas cylinder)
Reference Signs List 8: First fluid compressor 9: First fluid pressure gauge 10: First working space pressure gauge 11: First fluid supply system 12: First fluid valve exhaust system 13: First fluid valve outlet system 14: First fluid exhaust system 15: First fluid exhaust valve 16: First fluid pressure fluctuation valve 17: First fluid pressure adjustment means 18: First calculation means 19: First fluid flow rate measurement means 20: First fluid flow rate measurement value transmission means 21: Lower part of vessel 22: Second working space (second space)
23 Second fluid supply means (gas cylinder)
24 Second fluid compressor 25 Second fluid pressure gauge 26 Second working space pressure gauge 27 Second fluid supply system 28 Second fluid valve exhaust system 29 Second fluid valve outlet system 30 Second fluid exhaust system 31 Second fluid exhaust valve 32 Second fluid pressure fluctuation valve 33 Second fluid pressure adjustment means 34 Second calculation means 35 Signal input circuit 36 Control operation unit 37 Signal output circuit 38 Control operation display unit 39 First fluid maximum pressure 40 Second fluid minimum pressure 41 Pressure fluctuation 42 First fluid flow rate 43 Integrated flow rate 44 Number of cycles 45 Second fluid pressure 46 Concentration analysis means (concentration analyzer)
47 Data recording system 48 Second fluid circulation system 49 Second fluid circulation pump 50 Circulation system pressure reducing valve

Claims (3)

A characteristic test apparatus for evaluating characteristics and/or durability of a test piece in a fluid atmosphere, comprising:
a container for storing the test strip, the container being partitioned by the test strip into a first working space and a second working space each having a fixed volume;
a first fluid supply means for supplying a first fluid to the first working space formed between the container and the test piece contained therein;
a first fluid pressure adjusting means for adjusting the pressure of the first fluid supplied to the first working space to apply a repeatedly varying bending load to the test piece;
a first fluid flow rate measuring means for measuring a flow rate of the first fluid supplied to the first working space;
a second fluid supply means for supplying a second fluid to the second working space formed between the container and the test piece contained therein;
a second fluid pressure adjusting means for adjusting the pressure of the second fluid supplied to the second working space;
a calculation means for automatically adjusting the pressure of the second fluid pressure adjustment means to a new approximate pressure equilibrium state with the first fluid pressure as damage to the test piece progresses , based on flow rate measurement data of the first fluid measured by the first fluid flow rate measurement means;
A characteristic test device comprising: a second fluid supply means for supplying a second fluid, different from the first fluid in the first working space , to the second working space ;
a concentration analysis means for analyzing a change over time in the concentration of the first fluid contained in the second fluid, which cross-leaks into the second working space in a state of approximate pressure equilibrium between the first fluid pressure and the first fluid pressure, which continuously changes as the test piece breaks;
2. The characteristic test apparatus according to claim 1, further comprising: a circulation system for circulating the second fluid in a new approximate pressure equilibrium state with the first fluid pressure over a wide range as the damage of the test specimen progresses;
A circulation means as a circulation power source;
3. The characteristic test apparatus according to claim 1, further comprising:

Images