Hydrogen permeation dynamic testing device for simulating hydrogen-contacting pipe

Abstract

The invention provides a hydrogen permeation dynamic testing device for simulating a hydrogen-present pipe, which comprises: a first shell, the open end of which is connected with one side of a sample, a first chamber being defined between the first shell and the sample, the first chamber being used for storing hydrogen; the open end of the second shell is connected with the other side of the sample, a second cavity is defined between the second shell and the sample, the second cavity is used for containing electrolyte, an auxiliary electrode and a reference electrode are arranged on the second shell, the auxiliary electrode and the reference electrode penetrate through the second shell and then stretch into the second cavity, and the auxiliary electrode and the reference electrode are arranged in the second cavity. The auxiliary electrode and the reference electrode are immersed in the electrolyte; the stretcher is connected with the sample, and the stretcher is used for applying tensile force to the sample. According to the invention, the technical problem that a gas phase hydrogen permeation device in the prior art is used for testing the hydrogen permeation behavior of an unloaded sample and cannot test the change of the gas phase hydrogen permeation behavior of the pipeline steel under the tensile stress can be solved.

Description

Technical Field

[0001] This invention belongs to the field of metal vapor phase hydrogen permeation technology, specifically relating to a hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes. Background Technology

[0002] With rapid economic development and population growth, energy consumption is gradually increasing. The overuse of fossil fuels has caused serious environmental pollution, making the development of green and low-carbon energy an urgent priority. Currently known green and low-carbon energy sources include solar, wind, and biomass energy. However, due to geographical and climatic limitations, solar and wind power are mainly concentrated in the west, while energy consumption is primarily concentrated in eastern my country. Because of the difficulty in timely energy absorption, western regions generally experience problems such as wind and solar power curtailment. Converting unabsorbed electricity into hydrogen through renewable energy power generation technology can effectively solve these problems. Furthermore, hydrogen energy has advantages such as being environmentally friendly, having high energy conversion efficiency, wide availability, and energy storage capabilities. Therefore, hydrogen energy will be an important pathway for my country's low-carbon energy development. Transporting hydrogen through existing natural gas pipelines is the most economical and effective way to transport hydrogen on a large scale. However, when hydrogen is added to natural gas pipelines, the pipeline steel faces the problem of hydrogen permeation. The diffusion and accumulation of hydrogen in the pipeline steel can cause hydrogen damage, seriously threatening the safe operation of the pipeline. Therefore, it is necessary to study the hydrogen permeation behavior of pipeline steel under gaseous hydrogen, and use this as a basis for material selection and evaluation.

[0003] Most existing gas-phase hydrogen permeation devices test the hydrogen permeation behavior of unloaded samples. However, pipeline steel is inevitably affected by stress during service. Therefore, in order to study the changes in gas-phase hydrogen permeation behavior of pipeline steel when the load condition changes, it is necessary to design a simple, safe and easy-to-operate in-situ gas-phase tensile hydrogen permeation kinetic testing device.

[0004] Because existing gas-phase hydrogen permeation devices test the hydrogen permeation behavior of unloaded samples and cannot measure the changes in gas-phase hydrogen permeation behavior of pipeline steel under tensile stress, this invention studies and designs a hydrogen permeation kinetics testing device to simulate hydrogen-bearing pipes. Summary of the Invention

[0005] Therefore, the present invention provides a hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes, which can solve the technical problem that the existing gas-phase hydrogen permeation devices test the hydrogen permeation behavior of unloaded samples and cannot measure the changes in gas-phase hydrogen permeation behavior of pipeline steel under tensile stress.

[0006] To address the aforementioned problems, this invention provides a hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes, comprising: a first housing, the open end of which is connected to one side of a sample, the first housing and the sample forming a first chamber for storing hydrogen gas; a second housing, the open end of which is connected to the other side of the sample, the second housing and the sample forming a second chamber for holding an electrolyte, an auxiliary electrode and a reference electrode disposed on the second housing, the auxiliary electrode and the reference electrode penetrating the second housing and extending into the second chamber, and the auxiliary electrode and the reference electrode being immersed in the electrolyte; and a tensile testing machine connected to the sample, the tensile testing machine being used to apply tensile force to the sample.

[0007] In some embodiments, a flange is provided between the open end of the second housing and the sample, a first connector is provided on the side of the flange facing the sample, the first connector is connected to the first housing, the first connector is located on the side of the sample, and a second seal is provided between the first housing and the sample.

[0008] In some embodiments, a second connector is provided on the side of the flange facing away from the sample, the flange is connected to the second housing through the second connector, the flange has a central hole, the open end of the second housing is connected to the central hole, and a first sealing element is provided between the flange and the sample, between the inner peripheral wall of the flange, and between the flange and the second housing.

[0009] In some embodiments, the first housing is provided with a hydrogen inlet and a hydrogen outlet, and valve bodies are provided on the hydrogen outlet and the hydrogen inlet. One valve body is used to open or close the hydrogen inlet, and the other valve body is used to open or close the hydrogen outlet. A pressure gauge is also provided on the hydrogen inlet for detecting the pressure in the first chamber.

[0010] In some embodiments, the hydrogen permeation kinetics testing device simulating hydrogen-contaminated pipes is placed in an explosion-proof cabinet. The hydrogen outlet is connected to a fourth gas conduit, which is equipped with a hydrogen exhaust valve. One end of the fourth gas conduit facing away from the hydrogen outlet extends out of the explosion-proof cabinet, and the fourth gas conduit is used to discharge gas outside the explosion-proof cabinet.

[0011] In some embodiments, the second housing is provided with a nitrogen inlet and a nitrogen outlet, the auxiliary electrode and the reference electrode are located between the nitrogen inlet and the nitrogen outlet, and a connecting pipe is provided on the nitrogen inlet, the connecting pipe extending at least partially into the electrolyte.

[0012] In some embodiments, the hydrogen permeation kinetics testing device simulating hydrogen-contaminated pipes is placed in an explosion-proof cabinet. The nitrogen outlet is connected to a third gas conduit, which is equipped with a nitrogen exhaust valve. One end of the third gas conduit facing away from the nitrogen outlet extends out of the explosion-proof cabinet, and the third gas conduit is used to discharge gas outside the explosion-proof cabinet.

[0013] In some embodiments, the hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes further includes a hydrogen cylinder, the outlet of which is connected to the first chamber via a second gas conduit. The second gas conduit is equipped with a hydrogen cylinder switch and a hydrogen pressure reducing valve, which regulates the gas flow rate in the second gas conduit.

[0014] In some embodiments, the hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes further includes a nitrogen cylinder, the outlet of which is connected to the second chamber via a second gas conduit. The second gas conduit is equipped with a nitrogen cylinder switch and a nitrogen pressure reducing valve, which regulates the gas flow rate in the second gas conduit.

[0015] In some embodiments, the hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes is placed in a laboratory equipped with a hydrogen detector and a fan for transporting airflow from the laboratory to the outside. The explosion-proof cabinet is also equipped with a first gas pipeline for connecting the air inside and outside the explosion-proof cabinet.

[0016] The hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes provided by this invention has the following beneficial effects:

[0017] 1. The hydrogen permeation kinetics testing device for simulating hydrogen-containing pipes of the present invention can monitor the changes in gas-phase hydrogen permeation behavior of hydrogen-containing pipes in real time by means of electrochemical methods when the load state changes. Moreover, the hydrogen permeation kinetics testing device for simulating hydrogen-containing pipes of the present invention is easy to build, simple to operate, and safe and reliable.

[0018] 2. The hydrogen permeation kinetics testing device for simulating hydrogen-containing pipes of this invention is easy to prepare and the surface state of the sample is easy to control. It can be used to study the hydrogen permeation behavior of hydrogen-containing pipes under the coupling effect of hydrogen-doped environment and load. The hydrogen permeation kinetics testing device for simulating hydrogen-containing pipes of this invention has been used to test the hydrogen permeation curve of low-strength pipeline steel under load in real time. The test results show that the measurement results are accurate and stable. Attached Figure Description

[0019] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the hydrogen permeation kinetics testing device for simulating hydrogen-containing pipes according to the present invention.

[0021] Figure 2 This is a complementary enlarged view of the hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes of the present invention;

[0022] Figure 3 The present invention provides hydrogen permeation curves of pipeline steel under different tensile stresses in a pure hydrogen environment using a hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes.

[0023] The attached figures are labeled as follows:

[0024] 1. Hydrogen detector; 2. First gas pipeline; 3. Explosion-proof cabinet; 4. Hydrogen pressure reducing valve; 5. Hydrogen cylinder switch; 6. Hydrogen cylinder; 7. Nitrogen pressure reducing valve; 8. Nitrogen cylinder switch; 9. Nitrogen cylinder; 10. Second gas conduit; 11. Stretching machine; 12. Pressure display; 13. Ambient humidity display; 14. Control cabinet; 15. First main unit; 16. Ambient temperature display; 17. Electrochemical workstation; 18. Second main unit; 19. Indicator light; 20. Emergency switch; 21. Nitrogen. 21. Exhaust valve; 22. Hydrogen exhaust valve; 23. Third gas conduit; 24. Fan; 25. Fourth gas conduit; 26. Hydrogen inlet; 27. Valve body; 28. Pressure gauge; 29. ​​First housing; 30. Hydrogen outlet; 31. First connector; 32. Sample; 33. Second connector; 34. First seal; 35. Second housing; 36. Nitrogen inlet; 37. Auxiliary electrode; 38. Reference electrode; 39. Nitrogen outlet; 40. Flange; 41. Second seal. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0027] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0028] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0029] See also Figure 1-3As shown in the embodiment of the present invention, a hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes is provided, comprising: a first housing 29, the open end of the first housing 29 being connected to one side of a sample 32, the first housing 29 and the sample 32 forming a first chamber for storing hydrogen gas; a second housing 35, the open end of the second housing 35 being connected to the other side of the sample 32, the second housing 35 and the sample 32 forming a second chamber for holding an electrolyte, an auxiliary electrode 37 and a reference electrode 38 being disposed on the second housing 35, the auxiliary electrode 37 and the reference electrode 38 penetrating the second housing 35 and extending into the second chamber, and the auxiliary electrode 37 and the reference electrode 38 being immersed in the electrolyte; and a tensile machine 11, the tensile machine 11 being connected to the sample 32, the tensile machine 11 being used to apply tensile force to the sample 32. In this technical solution, tensile stress is applied to the sample using a tensile testing machine 11. Hydrogen gas is stored in the first chamber, and the electrolyte is contained in the second chamber. The change in hydrogen release current over time during loading can be detected in real time using the sample, auxiliary electrode 37, and reference electrode 38, improving the accuracy and stability of in-situ tensile gas-phase hydrogen permeation kinetics testing of hydrogen-contaminated pipes. Specifically, the electrolyte is 0.2 mol / L NaOH. The tensile testing machine 11 is located at either end of the sample 32, meaning it is arranged perpendicularly to the second shell 35 and the first shell 29. The side of the sample 32 closest to the second shell 35, the auxiliary electrode 37, and the reference electrode 38 are connected to an electrochemical workstation 17 for hydrogen permeation curve measurement. The sample 32, auxiliary electrode 37, and reference electrode 38 are immersed in the electrolyte.

[0030] In some embodiments, a flange 40 is provided between the open end of the second housing 35 and the sample 32. A first connector 31 is provided on the side of the flange 40 facing the sample 32. The first connector 31 is connected to the first housing 29, and a second sealing element 41 is provided between the first housing 29 and the sample. In this technical solution, the second sealing element 41 is an O-ring, the first connector 31 is an internal hexagon screw, and the first housing 29 is made of high-quality stainless steel to withstand high gas pressure and long-term hydrogen damage. The right side of the first housing 29 has an opening, and the sample 32 is vertically installed between the first housing 29 and the flange 40. The sample 32 is clamped between the first housing 29 and the flange 40 by four first connectors 31. The sample 32 is clamped during the tightening of the screws. The four first connectors 31 are located on both sides of the sample 32, that is, the sample 32 is located between the four first connectors 31. The sample 32 and the first housing 29 are sealed together by the second sealing element 41 to prevent hydrogen leakage.

[0031] In some embodiments, a second connecting member 33 is provided on the side of the flange 40 facing away from the sample 32. The flange 40 and the second housing 35 are connected through the second connecting member 33. The flange 40 has a central hole, and the open end of the second housing 35 communicates with the central hole. A first sealing member 34 is provided between the flange 40 and the sample 32, between the inner peripheral wall of the flange 40, and between the flange 40 and the second housing 35. In this technical solution, the first sealing member 34 is an I-shaped sealing ring, and the second connecting member 33 is a connecting bolt. The sample 32 and the flange 40 are sealed together by the first sealing member 34, and the first sealing member 34 can isolate the flange 40 from the solution in the anode tank 35. The right opening of the first housing 29 is opposite to the central opening of the first sealing member 34 installed on the flange 40. The flange 40 has four holes on its edge, corresponding to four holes on the left edge of the second housing 35. The flange 40 is connected to the second housing 35 via four second connectors 33. Tightening the second connectors 33 seals the second housing 35 with the sample 32, preventing electrolyte leakage from the second housing 35. Rubber rings are used to seal both sides of the sample. After clamping, when tension is applied to the sample, the shape of the rubber rings changes with the deformation of the sample, ensuring that the effective contact area between the tensile sample and the hydrogen or anolyte does not shift.

[0032] In some embodiments, the first housing 29 is provided with a hydrogen inlet 26 and a hydrogen outlet 30. Valve bodies 27 are provided on both the hydrogen outlet 30 and the hydrogen inlet 26. One valve body 27 is used to open or close the hydrogen inlet 26, and the other valve body 27 is used to open or close the hydrogen outlet 30. A pressure gauge 28 is also provided on the hydrogen inlet 26 to detect the gas pressure in the first chamber. In this technical solution, the opening or closing of the hydrogen outlet 30 and the hydrogen inlet 26 is controlled by the valve body 27, and the gas pressure in the first chamber is detected in real time by the pressure gauge 28, facilitating real-time regulation of the gas pressure in the first chamber.

[0033] In some embodiments, the hydrogen permeation kinetics testing device simulating hydrogen-bearing pipes is placed in an explosion-proof cabinet 3. The hydrogen outlet 30 is connected to a fourth gas conduit 25, which is equipped with a hydrogen exhaust valve 22. One end of the fourth gas conduit 25, facing away from the hydrogen outlet 30, extends outside the explosion-proof cabinet 3, and is used to exhaust gas outside the cabinet 3. In this technical solution, the first chamber needs to be purged during the experiment, and the hydrogen gas in the first chamber is exhausted outside the explosion-proof cabinet 3 during purging, ensuring the safety and accuracy of the experiment.

[0034] Preferably, the hydrogen permeation kinetics testing device simulating hydrogen-bearing pipes is placed in a laboratory. The hydrogen cylinder 6 and nitrogen cylinder 9 are placed in an explosion-proof cabinet 3. The hydrogen outlet 30 is connected to a fourth gas conduit 25, which is equipped with a hydrogen exhaust valve 22. The end of the fourth gas conduit 25 facing away from the hydrogen outlet 30 extends outside the laboratory, and is used to exhaust gas outside the laboratory. In this technical solution, the first chamber needs to be purged during the experiment. During purging, the hydrogen gas in the first chamber is exhausted outside the laboratory, ensuring the safety of the experiment.

[0035] In some embodiments, the second housing 35 is provided with a nitrogen inlet 36 and a nitrogen outlet 39. The auxiliary electrode 37 and the reference electrode 38 are located between the nitrogen inlet 36 and the nitrogen outlet 39. A connecting pipe is provided on the nitrogen inlet 36, and the connecting pipe extends at least partially into the electrolyte. In this technical solution, the electrolyte needs to be deoxygenated during the experiment. By having the connecting pipe extend at least partially into the electrolyte, the deoxygenation effect of the electrolyte is improved.

[0036] In some embodiments, the hydrogen permeation kinetics testing device simulating hydrogen-bearing pipes is placed in an explosion-proof cabinet 3. A third gas conduit 23 is connected to the nitrogen outlet 39, and a nitrogen exhaust valve 21 is installed on the third gas conduit 23. The end of the third gas conduit 23 facing away from the nitrogen outlet 39 extends outside the explosion-proof cabinet 3, and the third gas conduit 23 is used to discharge gas outside the explosion-proof cabinet 3. During the experiment, the electrolyte needs to be deoxygenated. During the deoxygenation process, the gas is discharged outside the explosion-proof cabinet 3 through the third gas conduit 23, ensuring the safety and accuracy of the experiment.

[0037] Preferably, the hydrogen permeation kinetics testing device simulating hydrogen-bearing pipes is placed in a laboratory. The hydrogen cylinder 6 and nitrogen cylinder 9 are placed in an explosion-proof cabinet 3. The nitrogen outlet 39 is connected to a third gas conduit 23, which is equipped with a nitrogen exhaust valve 21. The end of the third gas conduit 23 facing away from the nitrogen outlet 39 extends outside the laboratory, and is used to exhaust gas outside the laboratory. During the experiment, the electrolyte needs to be deoxygenated. During the deoxygenation process, the gas is exhausted outside the laboratory through the third gas conduit 23, ensuring the safety and accuracy of the experiment.

[0038] In some embodiments, the hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes further includes a hydrogen cylinder 6. The outlet of the hydrogen cylinder 6 is connected to the first chamber via a second gas conduit 10. The second gas conduit 10 is equipped with a hydrogen cylinder switch 5 and a hydrogen pressure reducing valve 4, which regulates the gas flow rate in the second gas conduit 10. The second seal 41 and the first connector 31 ensure that the hydrogen pressure in the first chamber remains constant under sample loading, allowing for real-time testing of the hydrogen permeation curve.

[0039] In some embodiments, the hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes further includes a nitrogen cylinder 9. The outlet of the nitrogen cylinder 9 is connected to the second chamber via a second gas conduit 10. The second gas conduit 10 is equipped with a nitrogen cylinder switch 8 and a nitrogen pressure reducing valve 7, which regulates the gas flow rate in the second gas conduit 10. An electrolyte inlet is provided on the second housing 35, and a valve body is provided at the inlet for opening or closing the electrolyte inlet.

[0040] In the hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes of the present invention, hydrogen cylinder 6 and nitrogen cylinder 9 are placed inside an explosion-proof cabinet 3. A hydrogen detector 1 is installed inside the explosion-proof cabinet 3. The top of the explosion-proof cabinet 3 is connected to the atmosphere through a first gas pipe 2. Above the laboratory where the hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes of the present invention is located, a hydrogen detector 1 and a fan 24 are installed. The fan 24 is an exhaust fan that continuously discharges gas into the atmosphere. A hydrogen cylinder 6 is equipped with a cylinder switch 5 and a hydrogen pressure reducing valve 4. The hydrogen outlet of the hydrogen cylinder 6 is connected to the hydrogen inlet 26 of the first housing 29 via a second gas conduit 10. The hydrogen pressure inside the hydrogen cylinder 6 is higher than the maximum hydrogen pressure required for testing. A pressure gauge 28 is installed on one side of the hydrogen inlet 26 of the first housing 29 to monitor the internal gas pressure. The gas flow rate to the first housing 29 is adjusted by adjusting the hydrogen pressure reducing valve 4 and the valve body 27. The valve body 27 is a needle valve 27. The hydrogen outlet 30 of the first housing 29 is connected to the hydrogen exhaust valve 22 and is connected to the atmosphere via a fourth gas conduit 25. A nitrogen cylinder 9 is equipped with a nitrogen cylinder switch 8 and a nitrogen pressure reducing valve 7. The nitrogen outlet of the nitrogen cylinder 9 is connected to the nitrogen inlet 36 of the second housing 35 via a second gas conduit 10. The nitrogen outlet 39 of the second housing 35 is connected to the nitrogen exhaust valve 21 and is connected to the atmosphere via a third gas conduit 23.

[0041] In some embodiments, the hydrogen permeation kinetics testing device simulating hydrogen-contaminated pipes is placed in an explosion-proof cabinet 3, which is equipped with a hydrogen detector 1. The explosion-proof cabinet 3 is located in a laboratory, which is equipped with a fan 24 for transporting airflow from the laboratory to the outside. The explosion-proof cabinet 3 is also equipped with a first gas pipe 2 for connecting the air inside and outside the explosion-proof cabinet 3.

[0042] Preferably, the hydrogen permeation kinetics testing device for simulating hydrogen-contaminated pipes is placed in a laboratory. The laboratory is equipped with a hydrogen detector 1 and a fan 24, which is used to transport the airflow inside the laboratory to the outside of the laboratory. The explosion-proof cabinet 3 is also equipped with a first gas pipe 2, which is used to connect the air inside and outside the explosion-proof cabinet 3.

[0043] The hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes of the present invention also includes a control cabinet 14. The control cabinet 14 is equipped with indicator lights 19, an emergency switch 20, an ambient humidity display 13, an ambient temperature display 16, a pressure display 12, a second host 18 connected to an electrochemical workstation, and a first host 15. The indicator lights 19, emergency switch 20, ambient humidity display 13, ambient temperature display 16, and pressure display 12 are respectively connected to the first host 15 via wiring. The first host 15 is a main control computer, and the second host 18 is a computer.

[0044] The hydrogen permeation kinetics testing device for simulating hydrogen-bearing pipes of the present invention is used to measure the high-pressure gas-phase hydrogen permeation kinetic parameters of the sample under tensile conditions. The sample needs to be pretreated and nickel-plated on one side before the kinetic parameters are measured.

[0045] The pretreatment process is as follows: the sample 32 is pretreated by grinding, and the sample thickness is kept uniform during the grinding process. Then, the sample is nickel plated on one side to prevent corrosion of the outer surface of the sample under anodic constant potential polarization, so as to ensure that effective hydrogen permeation data are obtained.

[0046] Before the test begins, open the nitrogen cylinder switch 8 and nitrogen pressure reducing valve 7 on the nitrogen cylinder 9, so that nitrogen enters the second chamber under the pressure difference between the nitrogen cylinder 9 and the electrolyte, and is discharged from the nitrogen outlet 39. During the test, nitrogen is continuously introduced to remove dissolved oxygen.

[0047] Hydrogen permeation performance testing process: The single-sided nickel-plated sample 32 is placed between the first housing 29 and the flange 40, with the nickel-plated side of the sample 32 placed on the side of the second housing 35. The sample 32, the first housing 29 and the second housing 35 are connected and fixed by the hexagonal screws 31, connecting bolts 33 and flange 40. The O-ring and I-shaped sealing ring are used to achieve a sealing effect. Then the sample 32 is installed and fixed on the tensile tester 11. Electrolyte is supplied to the second housing 35. The nitrogen cylinder switch 8 on the nitrogen cylinder 9 is opened, and the nitrogen pressure reducing valve 7 is adjusted to supply nitrogen into the second chamber. Nitrogen enters the second chamber under the pressure difference between the nitrogen cylinder 9 and the electrolyte and exits from the nitrogen outlet 39. Nitrogen is continuously supplied during the test to remove dissolved oxygen from the electrolyte. Simultaneously, the sample 32, auxiliary electrode 37, and reference electrode 38 are connected to the electrochemical workstation 17. After deoxygenation for 30 minutes, the electrochemical workstation 17 is started, and nitrogen is continuously supplied to the anode cell 35 during the measurement. The electrochemical workstation 17 is set to constant potential mode, with the potential set at 0.3V relative to the reference electrode. The current captured by the electrochemical workstation 17 is less than 5 × 10⁻⁶. -8 A / cm 2 Then, the hydrogen cylinder switch 5 on hydrogen cylinder 6 was opened, and the hydrogen pressure reducing valve 4 was adjusted to supply hydrogen to the first housing 29. After purging for 30 minutes, pressure build-up began, with a pressure of 0.2–4 MPa. The ambient temperature and humidity were recorded as the experimental test temperature. The electrochemical workstation 17 recorded the change in hydrogen release current over time. When the hydrogen atom diffusion steady state was established, the hydrogen release current reached its maximum value I. ∞ When tensile stress is applied to the sample, the electrochemical workstation 17 continuously records the change of hydrogen release current of the sample with time during the loading process. When the preset tensile force is reached, the loading is stopped. When the hydrogen release current basically does not change with time, the data recording is stopped and the experiment ends.

[0048] Furthermore, once the pressure build-up is complete, the experimental environment is established. The second shell 35 employs a three-electrode system, with the sample as the anode and the auxiliary electrode as the cathode. When hydrogen atoms diffused to the sample surface are oxidized to hydrogen ions, the electrochemical workstation can detect the current signal. The electrochemical workstation records the current between the auxiliary electrode and the sample. The potential difference between the reference electrode and the sample is maintained at 0.3V. During gas purging, the hydrogen inlet and outlet are open; during pressure build-up, the hydrogen inlet is open and the hydrogen outlet is closed; after pressure build-up is complete, both the hydrogen inlet and outlet are closed.

[0049] Furthermore, hydrogen molecules in the high-pressure metal chamber undergo dissociation and adsorption on the sample surface, and hydrogen atoms are adsorbed on the sample surface. Due to the difference in hydrogen atom concentration on both sides of the sample, hydrogen atoms diffuse from the side with higher concentration to the side with lower concentration. When hydrogen atoms diffuse to the side with lower concentration, that is, the sample side in contact with the anolyte electrolyte, the hydrogen atoms will be ionized into hydrogen ions under the action of the voltage difference between the reference electrode and the sample surface. There will be a current signal between the sample and the auxiliary electrode, and the electrochemical workstation will record this current signal.

[0050] Furthermore, the second housing 35 is connected to the electrochemical workstation 17, which applies a potential to the surface of the sample 32 to ensure that H diffuses to the sample surface in contact with the electrolyte in the second chamber and is ionized into H+, forming an anodic current.

[0051] Hydrogen-permeable pipelines are subjected to elastic or plastic tensile stress during actual operation, which alters their hydrogen permeation behavior and further affects their mechanical properties. Therefore, it is necessary to study the hydrogen permeation behavior of hydrogen-permeable pipelines under tensile stress. The surface condition of the sample has a significant impact on the gas-phase hydrogen permeation behavior, and different samples of the same material exhibit considerable differences in their gas-phase hydrogen permeation behavior. Therefore, using the same sample is essential to accurately reflect the hydrogen permeation behavior of hydrogen-permeable pipelines under tensile stress, making load coupling crucial.

[0052] Example

[0053] Hydrogen permeation measurement of samples under different tensile stresses in a pure hydrogen environment: Hydrogen gas is located inside the first shell 29, and the first chamber 29 is the hydrogen diffusion chamber; hydrogen molecules are converted into atomic H on the sample surface through physical adsorption and chemical adsorption. The anode cell constitutes the hydrogen anode chamber and is connected to the electrochemical workstation. A potential is applied to ensure that H diffuses from the inside of the sample to the outer surface of the sample and is ionized into H+, forming an anodic current.

[0054] Step one involves pretreating the sample by nickel plating the side of the sample in contact with the electrolyte to prevent corrosion of the sample surface under anodic constant potential polarization, thus ensuring the acquisition of effective hydrogen permeation data. The high-pressure metal gas chamber and the anode cell are installed in the gauge length section of the sample, and the sample is then fixed in the upper and lower clamps of the tensile testing machine.

[0055] Step 2: Add alkaline electrolyte to the second housing 35, and install the reference electrode and auxiliary electrode on the second housing 35. Both the reference electrode and the auxiliary electrode are inserted into the alkaline conductive solution. Open the nitrogen cylinder switch and pass the nitrogen pressure reducing valve to purge nitrogen from the anode electrolyte to remove oxygen.

[0056] Step 3: Start the electrochemical workstation and set it to constant potential mode. Set the potential to 0.3V relative to the Hg / HgO electrode, and ensure the current captured by the electrochemical workstation is less than 5 × 10⁻⁶. -8 A / cm2 Then, turn on the hydrogen cylinder switch and introduce hydrogen into the first chamber 29 through the hydrogen pressure reducing valve for gas washing. After washing for 30 minutes, start building up the pressure. The pressure is 0.2-4 MPa. Record the ambient temperature and humidity, which is the experimental test temperature.

[0057] Step 4: When the hydrogen pressure detected by pressure gauge 28 is within the preset pressure range, and when the current detected by the electrochemical workstation is stable at a certain value, set the loading parameters and perform loading. The electrochemical workstation obtains a hydrogen permeation curve that changes over time, which is used to characterize the effect of different tensile stresses on the hydrogen permeability coefficient.

[0058] See also Figure 3 As shown, Figure 3 The hydrogen permeation curves of X42 pipeline steel under different tensile stresses under a hydrogen pressure of 4 MPa in a pure hydrogen environment are obtained from actual measurements. When the instantaneous loading is increased to 300 MPa, which is less than the yield strength, the hydrogen permeation current decreases slightly, then rises rapidly and tends to stabilize; when the instantaneous loading is increased to 400 MPa, which is greater than the yield strength, the hydrogen permeation current decreases significantly, and after a period of time, the curve rises slowly and tends to stabilize.

[0059] The results show that the present invention can measure the hydrogen permeation parameters of samples in a pure hydrogen environment under different tensile stresses, and can also measure the hydrogen permeation parameters of samples in a hydrogen-doped gas environment under different tensile stresses, and can carry out hydrogen permeation measurement and kinetic studies of samples in pure hydrogen or hydrogen-doped environments under different tensile stresses.

[0060] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A device for testing the hydrogen permeation kinetics of a pipe simulating in- service conditions, characterized in that it comprises: It comprises: a first shell (29) with an open end connected to one side of a test sample (32), a first chamber being formed between the first shell (29) and the test sample (32) for storing hydrogen; a second shell (35) with an open end connected to the other side of the test sample (32), a second chamber being formed between the second shell (35) and the test sample (32) for containing electrolyte, the second shell (35) being provided with an auxiliary electrode (37) and a reference electrode (38), the auxiliary electrode (37) and the reference electrode (38) extending through the second shell (35) and into the second chamber, and the auxiliary electrode (37) and the reference electrode (38) being immersed in the electrolyte; a tensile machine (11) connected to the test sample (32) for applying tension to the test sample (32).

2. The device for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment according to claim 1, characterized in that: The open end of the second shell (35) and the test sample (32) are provided with a flange (40), the flange (40) being provided with a first connecting piece (31) on the side facing the test sample (32), the first connecting piece (31) being connected to the first shell (29), and the first connecting piece (31) being located on the side of the test sample, and a second sealing piece (41) being provided between the first shell (29) and the test sample.

3. The device for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen of claim 2, wherein: The side of the flange (40) facing away from the test sample (32) is provided with a second connecting piece (33), the flange (40) being connected to the second shell (35) through the second connecting piece (33), the flange (40) having a central hole, the open end of the second shell (35) being connected to the central hole, and a first sealing piece (34) being provided between the flange (40) and the test sample (32), the inner peripheral wall of the flange (40), and the flange (40) and the second shell (35).

4. The device for testing hydrogen permeation kinetics of a pipe in a simulated hydrogen environment according to claim 1, characterized in that: The first shell (29) is provided with a hydrogen inlet (26) and a hydrogen outlet (30), the hydrogen outlet (30) and the hydrogen inlet (26) are provided with valve bodies (27), one of the valve bodies (27) being used to open or close the hydrogen inlet (26), and the other valve body (27) being used to open or close the hydrogen outlet (30), and a pressure gauge (28) being further provided on the hydrogen inlet (26), the pressure gauge (28) being used to detect the gas pressure in the first chamber.

5. The apparatus for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment as claimed in claim 4 wherein: The device for testing the hydrogen permeation kinetics of the simulated hydrogen-resistant pipe is placed in an explosion-proof cabinet (3), the hydrogen outlet (30) is connected with a fourth gas conduit (25), the fourth gas conduit (25) is provided with a hydrogen exhaust valve (22), one end of the fourth gas conduit (25) extending out of the explosion-proof cabinet (3) away from the hydrogen outlet (30), and the fourth gas conduit (25) is used to exhaust gas out of the explosion-proof cabinet (3).

6. The apparatus for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment as claimed in claim 1 wherein: The second shell (35) is provided with a nitrogen inlet (36) and a nitrogen outlet (39), the auxiliary electrode (37) and the reference electrode (38) are located between the nitrogen inlet (36) and the nitrogen outlet (39), and the nitrogen inlet (36) is provided with a connecting pipe which extends at least partially into the electrolyte.

7. The apparatus for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment as claimed in claim 6 wherein: The hydrogen permeation kinetics testing device for simulating hydrogen environment pipe materials is placed in an explosion-proof cabinet (3), the nitrogen outlet (39) is communicated with a third gas conduit (23), the third gas conduit (23) is provided with a nitrogen exhaust valve (21), one end of the third gas conduit (23) which is away from the nitrogen outlet (39) extends out of the explosion-proof cabinet (3), and the third gas conduit (23) is used for discharging gas out of the explosion-proof cabinet (3).

8. The apparatus for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment as claimed in claim 1, wherein: The hydrogen permeation kinetics testing device for simulating hydrogen environment pipe materials further comprises a hydrogen cylinder (6), the outlet of the hydrogen cylinder (6) is communicated with the first chamber through a second gas conduit (10), the second gas conduit (10) is provided with a hydrogen cylinder switch (5) and a hydrogen pressure reducing valve (4), and the hydrogen pressure reducing valve (4) is used for adjusting the gas flow in the second gas conduit (10).

9. The apparatus for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment as claimed in claim 1 wherein: The hydrogen permeation kinetics testing device for simulating hydrogen environment pipe materials further comprises a nitrogen cylinder (9), the outlet of the nitrogen cylinder (9) is communicated with the second chamber through a second gas conduit (10), the second gas conduit (10) is provided with a nitrogen cylinder switch (8) and a nitrogen pressure reducing valve (7), and the nitrogen pressure reducing valve (7) is used for adjusting the gas flow in the second gas conduit (10).

10. The apparatus for testing hydrogen permeation kinetics of a pipe simulating in- service hydrogen environment as claimed in claim 1, wherein: The hydrogen permeation kinetics testing device for simulating hydrogen environment pipe materials is placed in an explosion-proof cabinet (3), the explosion-proof cabinet (3) is provided with a hydrogen detector (1), the explosion-proof cabinet (3) is arranged in a laboratory, the laboratory is provided with a fan (24), the fan (24) is used for conveying the air flow in the laboratory to the outside of the laboratory, and the explosion-proof cabinet (3) is further provided with a first gas conduit (2) which is used for communicating the air in and out of the explosion-proof cabinet (3).

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