High-pressure hydrogen environment mechanical property detection device

Abstract

The invention provides a high-pressure hydrogen environment mechanical property detection device, which belongs to the field of metal material performance testing and comprises a fatigue testing machine system, a gas supply system, a gas pressurization and detection system, a computer-aided system and a Venturi mixer. The fatigue testing machine system is connected with the gas pressurization and detection system through a seventh medium conveying pipe and an eighth medium conveying pipe, the fatigue testing machine system is connected with the computer-aided system through a second signal transmission line, and the gas supply system is connected with the Venturi mixer through a ninth medium conveying pipe and a tenth medium conveying pipe. And the gas pressurization and detection system is connected with the Venturi mixer through a sixth medium conveying pipe, and is connected with the computer-aided system through a first signal transmission line. The device can meet the high-pressure condition, an extensometer can be installed, X gas can be doped, and gas purity analysis can be carried out.

Description

Technical Field

[0001] The invention relates to the field of metal material performance testing, and in particular to a high-pressure hydrogen environment mechanical performance testing device. Background Art

[0002] Hydrogen provides a way to transition from fossil fuels to renewable energy, and pipelines are an economical and feasible way to transport hydrogen from remote production sites to terminals over long distances. However, the transportation of hydrogen poses a challenge to the smooth operation of existing gas pipelines. In addition to the safety measures required for raw natural gas, additional safety measures are required for the transportation of hydrogen. Pipeline steel will suffer from hydrogen embrittlement under hydrogen conditions, which is an important factor restricting the development of pipeline steel. Hydrogen embrittlement is a phenomenon of decreased mechanical properties, decreased plasticity, cracking or damage of materials caused by hydrogen in metal materials. Despite extensive research, the mechanism of hydrogen embrittlement is not yet fully understood. Existing studies have shown that the capture of hydrogen in different traps is related to the hydrogen charging method. Cathodic hydrogen charging causes hydrogen to be captured at reversible traps, while gas phase hydrogen charging causes hydrogen to be captured at irreversible traps. At present, most of the research results on hydrogen embrittlement use the cathode hydrogen charging method, while the actual hydrogen transmission environment is gaseous transmission. Therefore, the experimental results obtained due to different hydrogen charging methods may not have obvious guiding significance for actual working conditions. In order to reveal the mechanism of hydrogen embrittlement of pipeline steel under real hydrogen transportation conditions and promote the development of hydrogen energy, it is necessary to build corresponding material performance testing equipment.

[0003] Fatigue testing and tensile testing of metal materials are important ways to study material properties. In order to study the service performance of pipeline steel under real conditions, it is necessary to provide fatigue testing machines and tensile testing machines with actual test conditions and equipment. The main elements include: (1) providing a high-pressure hydrogen environment for the specimens undergoing mechanical property tests; (2) adding supporting hydrogen detection equipment and compressors for the test; (3) configuring X-gas bottles for the high-pressure hydrogen environment required for the test. At present, the hydrogen filling device for the mechanical property test of metal materials under hydrogen environment mainly adopts a reactor structure, which is currently the more widely used structure. However, the design and development of this type of equipment faces the following key technical issues.

[0004] (1) No extensometer clamping point

[0005] When using a reactor as a high-pressure hydrogen tank, the reactor is large in structure, making it difficult to install an extensometer. When conducting a tensile test, the displacement is generally calculated by the change in the position of the beam, and when conducting a fatigue test, only a stress fatigue test can be performed. In some design cases, the extensometer is placed inside the reactor, and the data line passes through the reactor body. This design weakens the pressure-bearing capacity of the reactor.

[0006] (2) It does not have the function of adding X gas into hydrogen

[0007] In actual hydrogen pipeline transportation, hydrogen may contain other gases such as nitrogen and methane. The presence of these gases can affect metal hydrogen embrittlement, but the existing design cases do not take the impact of these gases into account.

[0008] (3) Lack of corresponding gas purity analysis equipment

[0009] The analysis of the composition of high-pressure gas is an essential step in studying the hydrogen embrittlement ratio in a hydrogen environment. In previous designs, the hydrogen blending ratio was usually controlled by adjusting the pressure valves at the outlets of the nitrogen and hydrogen cylinders. This operation caused great uncertainty in the blending ratio of the mixed gas.

[0010] (4) Sample processing is complex

[0011] When a reactor is used as a high-pressure hydrogen tank structure, since the specimens need to be installed inside the reactor body, a rod-shaped specimen is often required and an external thread needs to be opened in the clamping section to connect with the internal thread of the slidable pull rod on the upper and lower end covers of the reactor. This design form is difficult to process specimens, requiring not only turning and polishing, but also threading. Summary of the invention

[0012] The object of the present invention is to provide a high-pressure hydrogen environment mechanical property detection device, which can meet high-pressure conditions, can be installed with an extensometer, can be mixed with X gas, and can perform gas purity analysis.

[0013] To achieve the above object, the present invention provides the following technical solutions:

[0014] A high-pressure hydrogen environment mechanical property detection device is characterized by comprising a fatigue testing machine system, a gas supply system, a gas pressurization and detection system, a computer-aided system and a Venturi mixer.

[0015] The fatigue testing machine system is connected to the gas pressurization and detection system through the seventh medium delivery pipe and the eighth medium delivery pipe, the fatigue testing machine system is connected to the computer-aided system through the second signal transmission line, the gas supply system is connected to the Venturi mixer through the ninth medium delivery pipe and the tenth medium delivery pipe, the gas pressurization and detection system is connected to the Venturi mixer through the sixth medium delivery pipe, and the gas pressurization and detection system is connected to the computer-aided system through the first signal transmission line.

[0016] Furthermore, the fatigue testing machine system includes a fatigue testing machine and a test unit. The fatigue testing machine includes a lower chuck, an upper chuck, a touch panel and a data transmission interface. The test unit is installed between the upper chuck and the lower chuck. The touch panel is used to control the displacement of the lower chuck.

[0017] Furthermore, the test unit includes a metal specimen, an inner sealing gasket, an outer sealing gasket, an extensometer and a high-pressure hydrogen box, the high-pressure hydrogen box includes a concave pressure-bearing shell and a convex pressure-bearing shell, the concave pressure-bearing shell includes a first wing plate, a first slot, a first air outlet and a first air inlet, and the convex pressure-bearing shell includes a first sealing end face, a second sealing end face, a boss, a slot, a second slot and a second wing plate.

[0018] The concave pressure-bearing shell is a hemispherical cavity, and first wing plates are provided at both ends of the maximum diameter of the concave pressure-bearing shell cavity, and a first slot is provided on the first wing plate. A first air outlet and a first air inlet with external threads are provided on the outer wall of the concave pressure-bearing shell cavity. The convex pressure-bearing shell is a hemispherical cavity, and second wing plates are provided at both ends of the maximum diameter of the convex pressure-bearing shell cavity, and a second slot is provided on the second wing plate. The wall surface of the convex pressure-bearing shell cavity is provided with a slot for installing a plate-shaped specimen and a boss protruding from the diameter end face.

[0019] The parallel length portion of the metal sample is placed in the notch of the convex pressure-bearing shell, the inner sealing gasket is arranged on the second sealing end surface, the outer sealing gasket is arranged on the first sealing end surface, the notch is cast with sealant, the concave pressure-bearing shell and the convex pressure-bearing shell are pressed from both sides and fixed by bolts, and the extensometer is installed on the sample by a rubber band.

[0020] Furthermore, the gas supply system includes a first vortex flowmeter, a first medium delivery pipe, a first pressure reducing valve, an X gas bottle, a nitrogen bottle, a second pressure reducing valve, a second medium delivery pipe, a second vortex flowmeter, a third vortex flowmeter, a third medium delivery pipe, a third pressure reducing valve and a hydrogen bottle.

[0021] The X gas cylinder, nitrogen cylinder and hydrogen cylinder are arranged in a row on a horizontal ground; the X gas cylinder is provided with a first pressure reducing valve, a first vortex flowmeter is provided on the upper side of the first pressure reducing valve, the first pressure reducing valve is connected to the air inlet of the first vortex flowmeter through a first medium delivery pipe; the nitrogen cylinder is provided with a second pressure reducing valve, a second vortex flowmeter is provided on the upper side of the second pressure reducing valve, the second pressure reducing valve is connected to the air inlet of the second vortex flowmeter through a second medium delivery pipe; the hydrogen cylinder is provided with a third pressure reducing valve, a third vortex flowmeter is provided on the upper side of the third pressure reducing valve, and the third pressure reducing valve is connected to the air inlet of the third vortex flowmeter through a third medium delivery pipe.

[0022] Furthermore, the air outlet of the first vortex flowmeter is connected to the Venturi mixer via a ninth medium delivery pipe, and the air outlets of the second vortex flowmeter and the third vortex flowmeter are connected to the Venturi mixer via a tenth medium delivery pipe.

[0023] Furthermore, the gas pressurization and detection system includes a gas purity analysis device, an exhaust gas treatment device, a fourth medium delivery pipe, a fifth medium delivery pipe, a water collecting tank, table No. 1, and a compressor. The gas purity analysis device is arranged on table No. 1, the compressor is arranged at the lower end of table No. 1, the exhaust gas treatment device is placed at the highest point parallel to the gas purity analysis device, and the water collecting tank is arranged on the horizontal ground on one side of the compressor.

[0024] The gas purity analysis device includes a first data transmission port, a second air inlet, a drain port and a second air outlet. The first data transmission port is arranged on one side of the upper part of the gas purity analysis device, and the second air inlet, the drain port and the second air outlet are arranged at the lower end of the gas purity analysis device. Table No. 1 is provided with holes corresponding to the second air inlet, the drain port and the second air outlet. The drain port is connected to the water collecting tank through a fifth medium delivery pipe, and the second air outlet is connected to the exhaust gas treatment device through a fourth medium delivery pipe.

[0025] Furthermore, the air inlet of the compressor is connected to the Venturi mixer through a sixth medium delivery pipe, the air outlet of the compressor is connected to the first air inlet through an eighth medium delivery pipe, and the second air inlet is connected to the first air outlet through a seventh medium delivery pipe.

[0026] Furthermore, the computer-aided system includes table No. 2, a computer, and a data processor. The computer and the data processor are respectively arranged on table No. 2. The data processor is provided with a second data transmission port and a third data transmission port. The second data transmission port is connected to the first data transmission port through a first signal transmission line, and the third data transmission port is connected to the data transmission interface through a second signal transmission line.

[0027] Furthermore, the outer diameter of the inner sealing gasket is consistent with the outer diameter of the boss, the inner diameter of the inner sealing gasket is consistent with the inner diameter of the boss, and the inner diameter of the outer sealing gasket is consistent with the outer diameter of the boss.

[0028] Advantages of the present invention:

[0029] 1. The present invention reasonably designs the structure and size of the high-pressure hydrogen box and places it inside the extensometer, thus avoiding the problem that the extensometer cannot be clamped when the reactor is used as a high-pressure container. At the same time, it can not only conveniently carry out low-cycle fatigue tests and slow strain rate tensile tests, but also avoid the problem of dangerous points caused by the opening of traditional reactors.

[0030] 2. The present invention realizes the function of mixing other gases into high-pressure hydrogen by adding X gas bottles, which can simulate the actual transportation conditions more realistically, and provides appropriate experimental conditions for studying the promotion or inhibition of metal hydrogen embrittlement by other gases.

[0031] 3. The present invention overcomes the drawback that the traditional test can only conduct pure hydrogen or hydrogen-doped tests under different pressure conditions by controlling the pressure ratio by adding a gas purity analysis device, and realizes the adjustment of different gas distribution ratios by detecting the composition of the introduced gas. It weakens the uncertainty of the traditional pressure-regulated gas mixing ratio and increases the selection abundance of test variables.

[0032] 4. The invention rationally designs the structure of the high-pressure hydrogen box so that it can be conveniently matched with the plate-shaped specimen first, without having to be processed into a rod-shaped specimen with an external thread, thus avoiding the steps of turning and tapping.

[0033] 5. The hydrogen box provides high-pressure in-situ hydrogen charging conditions for the sample, so that the sample can be tested for mechanical properties in a more realistic hydrogen environment, avoiding the disadvantage of electrochemical corrosion of the sample in traditional electrochemical hydrogen charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 It is a structural schematic diagram of the fatigue testing machine system in the present invention;

[0036] Figure 3 It is a schematic diagram of the structure of the test unit coordination in the present invention;

[0037] Figure 4 It is a structural schematic diagram of the high-pressure hydrogen box in the present invention;

[0038] Figure 5 It is a schematic diagram of the structure of the gas supply system in the present invention;

[0039] Figure 6 It is a structural schematic diagram of the gas pressurization and detection system of the present invention;

[0040] Figure 7 It is a structural schematic diagram of the computer-aided system in the present invention;

[0041] In the figure: 1. fatigue testing machine system, 1-1. fatigue testing machine, 1-1-1. lower chuck, 1-1-2. upper chuck, 1-1-3. touch panel, 1-1-4. data transmission interface, 1-2. test unit, 1-2-1. metal sample, 1-2-2. concave pressure shell, 1-2-2-1. first wing plate, 1-2-2-2. first slot, 1-2-2-3. first air outlet, 1 -2-2-4, first air inlet, 1-2-3, inner sealing gasket, 1-2-4, outer sealing gasket, 1-2-5, extensometer, 1-2-6, convex pressure shell, 1-2-6-1, first sealing end face, 1-2-6-2, second sealing end face, 1-2-6-3, boss, 1-2-6-4, notch, 1-2-6-5, second slot, 1-2-6-6, second wing plate;

[0042] 2. Gas supply system, 2-1. First vortex flowmeter, 2-2. First medium delivery pipe, 2-3. First pressure reducing valve, 2-4. X gas bottle, 2-5. Nitrogen bottle, 2-6. Second pressure reducing valve, 2-7. Second medium delivery pipe, 2-8. Second vortex flowmeter, 2-9. Third vortex flowmeter, 2-10. Third medium delivery pipe, 2-11. Third pressure reducing valve, 2-12. Hydrogen bottle;

[0043] 3. Gas pressurization and detection system, 3-1. Gas purity analysis device, 3-1-1. First data transmission port, 3-1-2. Second air inlet, 3-1-3. Drain port, 3-1-4. Second air outlet, 3-2. Tail gas treatment device, 3-3. Fourth medium delivery pipe, 3-4. Fifth medium delivery pipe, 3-5. Water collecting tank, 3-6. Table No. 1, 3-7. Compressor;

[0044] 4. Computer-aided system, 4-1. Table No. 2, 4-2. Computer, 4-3. Data processor, 4-3-1. Second data transmission port, 4-3-2. Third data transmission port;

[0045] 5. Sixth medium delivery pipe,

[0046] 6. The first signal transmission line,

[0047] 7. The second signal transmission line,

[0048] 8. Seventh medium delivery pipe,

[0049] 9. The eighth medium delivery pipe,

[0050] 10. Venturi mixer,

[0051] 11. Ninth medium delivery pipe

[0052] 12. Tenth medium delivery pipe. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0054] like Figure 1 As shown, a high-pressure hydrogen environment mechanical property detection device includes a fatigue testing machine system 1, a gas supply system 2, a gas pressurization and detection system 3, a computer-aided system 4 and a Venturi mixer 10.

[0055] The fatigue testing machine system 1 is connected to the gas pressurization and detection system 3 through the seventh medium delivery pipe 8 and the eighth medium delivery pipe 9, the fatigue testing machine system 1 is connected to the computer-aided system 4 through the second signal transmission line 7, the gas supply system 2 is connected to the Venturi mixer 10 through the ninth medium delivery pipe 11 and the tenth medium delivery pipe 12, the gas pressurization and detection system 3 is connected to the Venturi mixer 10 through the sixth medium delivery pipe 5, and the gas pressurization and detection system 3 is connected to the computer-aided system 4 through the first signal transmission line 6.

[0056] As a preferred embodiment of the present invention, Figure 2 As shown, the fatigue testing machine system 1 includes a fatigue testing machine 1-1 and a test unit 1-2, the fatigue testing machine 1-1 includes a lower clamp 1-1-1, an upper clamp 1-1-2, a touch panel 1-1-3 and a data transmission interface 1-1-4, the test unit 1-2 is installed between the upper clamp 1-1-2 and the lower clamp 1-1-1, and the touch panel 1-1-3 is used to control the displacement of the lower clamp 1-1-1. The fatigue testing machine 1-1 can perform fatigue tests and tensile tests on the same machine through different software.

[0057] As a preferred embodiment of the present invention, Figure 3 and Figure 4As shown, the test unit 1-2 includes a metal specimen 1-2-1, an inner sealing gasket 1-2-3, an outer sealing gasket 1-2-4, an extensometer 1-2-5 and a high-pressure hydrogen box, the high-pressure hydrogen box includes a concave pressure-bearing shell 1-2-2 and a convex pressure-bearing shell 1-2-6, the concave pressure-bearing shell 1-2-2 includes a first wing plate 1-2-2-1, a first slot 1-2-2-2, a first air outlet 1-2-2-3 and a first air inlet 1-2-2-4, the convex pressure-bearing shell 1-2-6 includes a first sealing end face 1-2-6-1, a second sealing end face 1-2-6-2, a boss 1-2-6-3, a slot 1-2-6-4, a second slot 1-2-6-5 and a second wing plate 1-2-6-6.

[0058] The concave pressure-bearing shell 1-2-2 is a hemispherical cavity, and first wing plates 1-2-2-1 are provided at both ends of the maximum diameter of the cavity of the concave pressure-bearing shell 1-2-2, and the first wing plate 1-2-2-1 is provided with a first slot 1-2-2-2, and the outer wall of the cavity of the concave pressure-bearing shell 1-2-2 is provided with a first air outlet 1-2-2-3 with external threads and a first air inlet 1-2-2-4, and the convex pressure-bearing shell 1-2-6 is a hemispherical cavity, and second wing plates 1-2-6-6 are provided at both ends of the maximum diameter of the cavity of the convex pressure-bearing shell 1-2-6, and the second wing plate 1-2-6-6 is provided with a second slot 1-2-6-5, and the cavity wall of the convex pressure-bearing shell 1-2-6 is provided with a slot 1-2-6-4 for installing a plate-shaped specimen and a boss 1-2-6-3 protruding from the diameter end face.

[0059] The parallel length portion of the metal sample 1-2-1 is placed in the notch 1-2-6-4 of the convex pressure-bearing shell 1-2-6, the inner sealing gasket 1-2-3 is arranged on the second sealing end face 1-2-6-2, and the outer sealing gasket 1-2-4 is arranged on the first sealing end face 1-2-6-1. The notch 1-2-6-4 is cast with sealant, and the concave pressure-bearing shell 1-2-2 and the convex pressure-bearing shell 1-2-6 are pressed from both sides and fixed by bolts to form a closed high-pressure chamber. The extensometer 1-2-5 is installed on the sample 1-2-1 by a rubber band.

[0060] As a preferred embodiment of the present invention, Figure 5 As shown, the gas supply system includes a first vortex flowmeter 2-1, a first medium delivery pipe 2-2, a first pressure reducing valve 2-3, an X gas bottle 2-4, a nitrogen bottle 2-5, a second pressure reducing valve 2-6, a second medium delivery pipe 2-7, a second vortex flowmeter 2-8, a third vortex flowmeter 2-9, a third medium delivery pipe 2-10, a third pressure reducing valve 2-11 and a hydrogen bottle 2-12.

[0061] The X gas bottle 2-4, the nitrogen bottle 2-5 and the hydrogen bottle 2-12 are arranged in a row on the horizontal ground. The X gas bottle 2-4 is provided with a first pressure reducing valve 2-3, and a first vortex flowmeter 2-1 is provided on the upper side of the first pressure reducing valve 2-3. The first pressure reducing valve 2-3 is connected to the air inlet of the first vortex flowmeter 2-1 through the first medium delivery pipe 2-2. The nitrogen bottle 2-5 is provided with a second pressure reducing valve 2-6, and a second vortex flowmeter 2-8 is provided on the upper side of the second pressure reducing valve 2-6. The second pressure reducing valve 2-6 is connected to the air inlet of the second vortex flowmeter 2-8 through the second medium delivery pipe 2-7. The hydrogen bottle 2-12 is provided with a third pressure reducing valve 2-11, and a third vortex flowmeter 2-9 is provided on the upper side of the third pressure reducing valve 2-11. The third pressure reducing valve 2-11 is connected to the air inlet of the third vortex flowmeter 2-9 through the third medium delivery pipe 2-10.

[0062] The hydrogen cylinder 2-12 is a high-purity hydrogen cylinder. When the bottled hydrogen is used as tail gas, the residual pressure in the bottle should be kept at 0.5MPa, and the minimum residual pressure should not be less than 0.25MPa. The nitrogen cylinder 2-5 is a high-purity hydrogen cylinder. When the bottled nitrogen is used as tail gas, the residual pressure in the bottle should be kept at 0.5MPa, and the minimum residual pressure should not be less than 0.25MPa. The X gas cylinder 2-4 contains other gases besides nitrogen and hydrogen, and can be used to study the effect of other gases mixed in hydrogen on hydrogen embrittlement of pipeline steel.

[0063] As a preferred embodiment of the present invention, the air outlet of the first vortex flowmeter 2-1 is connected to the Venturi mixer 10 through the ninth medium delivery pipe 11, and the air outlets of the second vortex flowmeter 2-8 and the third vortex flowmeter 2-9 are connected to the Venturi mixer 10 through the tenth medium delivery pipe 12.

[0064] The Venturi mixer 10 can ensure smooth delivery of each fluid before any combination of hydrogen, nitrogen and X gas enters the compressor, avoiding the mixing ratio being affected by the unbalanced delivery pressure of each gas. The Venturi mixer 10 ensures that the outlet pressure of the material reaches the required pressure under the condition of ensuring the flow rate of the branch flow.

[0065] As a preferred embodiment of the present invention, Figure 6 As shown, the gas pressurization and detection system 3 includes a gas purity analysis device 3-1, an exhaust gas treatment device 3-2, a fourth medium delivery pipe 3-3, a fifth medium delivery pipe 3-4, a water collecting tank 3-5, table No. 1 3-6, and a compressor 3-7. The gas purity analysis device 3-1 is arranged on table No. 1 3-6, the compressor 3-7 is arranged at the lower end of table No. 1 3-6, the exhaust gas treatment device 3-2 is placed at the highest point parallel to the gas purity analysis device 3-1, and the water collecting tank 3-5 is arranged on the horizontal ground on one side of the compressor 3-7.

[0066] The gas purity analysis device 3-1 includes a first data transmission port 3-1-1, a second air inlet 3-1-2, a drain port 3-1-3 and a second air outlet 3-1-4, the first data transmission port 3-1-1 is arranged on the upper side of the gas purity analysis device 3-1, the second air inlet 3-1-2, the drain port 3-1-3 and the second air outlet 3-1-4 are arranged at the lower end of the gas purity analysis device 3-1, the table No. 1 3-6 is provided with holes corresponding to the second air inlet 3-1-2, the drain port 3-1-3 and the second air outlet 3-1-4, the drain port 3-1-3 is connected to the water collecting tank 3-5 through the fifth medium delivery pipe 3-4, and the second air outlet 3-1-4 is connected to the exhaust gas treatment device 3-2 through the fourth medium delivery pipe 3-3.

[0067] The gas purity analysis device 3-1 can realize continuous online monitoring of multiple gases, remote signal transmission, and has an alarm function for excessive concentration. Its core component is a hydrogen purity analyzer with a range of 0-100% Vol, an allowable error of ≦±2% (FS), a minimum reading of 0.01% Vol, and a response time of ≦20s.

[0068] As a preferred embodiment of the present invention, the air inlet of the compressor 3-7 is connected to the Venturi mixer 10 through the sixth medium delivery pipe 5, the air outlet of the compressor 3-7 is connected to the first air inlet 1-2-2-4 through the eighth medium delivery pipe 9, and the second air inlet 3-1-2 is connected to the first air outlet 1-2-2-3 through the seventh medium delivery pipe 8.

[0069] The compressor 3-7 uses compressed air as the gas source to pressurize the hydrogen. A booster pump can be used to provide a small amount of local high-pressure gas. After pressurization, the internal pressure of the high-pressure hydrogen tank reaches 20Mpa.

[0070] As a preferred embodiment of the present invention, Figure 7 As shown, the computer-aided system 4 includes table number 4-1, a computer 4-2, and a data processor 4-3. The computer 4-2 and the data processor 4-3 are respectively arranged on table number 4-1. The data processor 4-3 is provided with a second data transmission port 4-3-1 and a third data transmission port 4-3-2. The second data transmission port 4-3-1 is connected to the first data transmission port 3-1-1 via a first signal transmission line 6, and the third data transmission port 4-3-2 is connected to the data transmission interface 1-1-4 via a second signal transmission line 7.

[0071] As a preferred embodiment of the present invention, the outer diameter of the inner sealing gasket 1-2-3 is consistent with the outer diameter of the boss 1-2-6-3, the inner diameter of the inner sealing gasket 1-2-3 is consistent with the inner diameter of the boss 1-2-6-3, and the inner diameter of the outer sealing gasket 1-2-4 is consistent with the outer diameter of the boss 1-2-6-3.

[0072] Working principle of this device:

[0073] The minimum wall thickness of the high-pressure hydrogen tank is 2mm, and for safety reasons, the minimum wall thickness at the thread is 1mm. According to the calculation formula for the maximum allowable working pressure of the pressure vessel spherical shell and spherical head specified in GB-150

[0074]

[0075] Where S: wall thickness (mm).

[0076] [σ] t :Allowable stress (kgf / cm 2 ), the allowable stress of AISI304 stainless steel is 215MPa, and the allowable stress of AISI316 stainless steel is 240Mpa. Combined with the selected 3D printing material, the smaller value is selected. The allowable stress of this device is 21510.197=2192.335kgf / cm 2 .

[0077] Welding seam coefficient: This device is made of stainless steel and processed by CNC in one piece, and the welding seam coefficient is 1.

[0078] C: Additional wall thickness. This device does not require additional wall thickness, so the additional wall thickness is 0.

[0079] D i : Diameter (mm).

[0080] So [P] = 2192.335 kg / cm 2 ≈21MPa.

[0081] From this we can see that the theoretical working pressure of the high-pressure hydrogen tank is P∈[0,21]MPa.

[0082] The sample is wrapped in a high-pressure hydrogen box to create the high-pressure hydrogen environment required for the test. A vortex flowmeter is used to control the amount of nitrogen, hydrogen and X gas mixed in to adjust the hydrogen environment. The instantaneous gas composition is obtained by measuring the changes in the proportion of different component gases in the gas purity analyzer.

[0083] The operation steps of this device are as follows: (This test step is explained by taking fatigue test as an example, the test pressure is 5Mpa, the gas in the X gas bottle is methane, and hydrogen: nitrogen: methane = 1:1:1 is introduced)

[0084] 1) Draw the specific dimensions of the fatigue specimen according to the national standard and process it with a wire cutting machine. A metal plate specimen was used for the test. The specimen was taken from a metal plate with a thickness of 15 mm, shaped in the thickness direction, and designed with reference to the national standard for fatigue test. Finally, the plate specimen with the dimensions of 150 mm long, 10 mm wide, 5 mm thick, parallel section length L = 50 mm, parallel section width H = 6 mm, and transition arc radius r = 20 mm was designed. After the wire cutting machine processing, the specimen was ground on sandpaper in sequence. The grain sizes of the sandpaper used were 150#, 400#, 800#, 1000#, and 1500#, respectively. Each time the sandpaper was changed, the grinding direction of the specimen was changed by 90°. When grinding the specimen, it should be noted that the previous grinding marks must be completely removed before the next sandpaper can be used, and it is necessary to ensure that the metal surface at the parallel length is smooth and there are no microcracks visible to the naked eye.

[0085] 2) The polished fatigue specimen is embedded in the groove 1-2-6-4 of the convex pressure shell 1-2-6 of the high-pressure hydrogen tank, and the metal specimen 1-2-1 is cast and sealed with sealing silicone rubber on the contact surface with the tank body. After the sealing silicone rubber is set, the inner sealing gasket 1-2-3 is placed in the end face corresponding to the boss 1-2-6-3, and the outer sealing gasket 1-2-4 is placed on the outside of the outer diameter surface of the boss 1-2-6-3. Subsequently, the two parts of the high-pressure hydrogen tank, namely the concave pressure shell 1-2-2 and the convex pressure shell 1-2-6, are pressed together and fixed with three fastening bolts on each side wing plate.

[0086] 3) After turning on the fatigue testing machine 1-1 and completing the connections according to the operating manual, first clamp the high-pressure hydrogen box that fixes the metal sample 1-2-1 on the chuck of the fatigue testing machine according to the standard, then fix the extensometer 1-2-5 on the metal sample 1-2-1 with a rubber band, and then connect the pipeline and data transmission line 1-1-4.

[0087] 4) Open the professional data monitoring software GMMS of the gas purity analysis device 3-1 according to regulations, then open the valves of the hydrogen cylinder 2-12, nitrogen cylinder 2-5, and X gas cylinder 2-4 and adjust the flow rate to 1m 3 / h. When the GMMS software detects that the purity ratio of the gas is stable at 1:1:1, the compressor test pressure is set and compressor 3-7 is started to pressurize the high-pressure hydrogen tank. When the pressure gauge on the outlet side of compressor 3-7 shows a pressure of 5Mpa, the fatigue test is started in the DynaTestExpert software.

[0088] 5) After the test is triggered to end, save the data in GMMS and DynaTestExpert software, then turn off the compressor 3-7 and release the pressure on the high-pressure hydrogen tank. When the internal pressure of the high-pressure hydrogen tank is zero, turn off the power switch of the gas purity analysis device 3-1. Remove the extensometer and the sample from the fatigue testing machine 1-1 according to the operating requirements, and then remove the high-pressure hydrogen tank device. Next, package the metal sample 1-2-1 to protect the fracture, remove the sealing silicone remaining on the high-pressure hydrogen tank body for next use, and finally turn off the main power of the fatigue testing machine 1-1 according to regulations.

[0089] In summary, the present invention meets the design requirements of a high-pressure hydrogen environment mechanical property testing device, achieves the purpose of performing performance testing on the sample in a hydrogen environment with a stable pressure, overcomes the shortcomings of existing designs, and provides a new test device for research.

[0090] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can still adjust the technical solutions described in the above embodiments or replace some of the technical features by equivalents. Therefore, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A high-pressure hydrogen environment mechanical properties testing device, characterized in that: It comprises a fatigue testing machine system (1), a gas supply system (2), a gas pressurization and detection system (3), a computer-aided system (4) and a venturi mixer (10); The fatigue testing machine system (1) is connected to the gas pressurization and detection system (3) via the seventh medium delivery pipe (8) and the eighth medium delivery pipe (9), the fatigue testing machine system (1) is connected to the computer-aided system (4) via the second signal transmission line (7), the gas supply system (2) is connected to the Venturi mixer (10) via the ninth medium delivery pipe (11) and the tenth medium delivery pipe (12), the gas pressurization and detection system (3) is connected to the Venturi mixer (10) via the sixth medium delivery pipe (5), and the gas pressurization and detection system (3) is connected to the computer-aided system (4) via the first signal transmission line (6).

2. A high-pressure hydrogen environment mechanical properties detection device according to claim 1, characterized in that: The fatigue testing machine system (1) comprises a fatigue testing machine (1-1) and a testing unit (1-2); the fatigue testing machine (1-1) comprises a lower chuck (1-1-1), an upper chuck (1-1-2), a touch panel (1-1-3) and a data transmission interface (1-1-4); the testing unit (1-2) is installed between the upper chuck (1-1-2) and the lower chuck (1-1-1); and the touch panel (1-1-3) is used to control the displacement of the lower chuck (1-1-1).

3. A high-pressure hydrogen environment mechanical properties detection device according to claim 2, characterized in that: The test unit (1-2) comprises a metal specimen (1-2-1), an inner sealing gasket (1-2-3), an outer sealing gasket (1-2-4), an extensometer (1-2-5) and a high-pressure hydrogen box; the high-pressure hydrogen box comprises a concave pressure-bearing shell (1-2-2) and a convex pressure-bearing shell (1-2-6); the concave pressure-bearing shell (1-2-2) comprises a first wing plate (1-2-2-1), a first slot hole (1-2-2-2), a first air outlet (1-2-2-3) and a first air inlet (1-2-2-4); the convex pressure-bearing shell (1-2-6) comprises a first sealing end face (1-2-6-1), a second sealing end face (1-2-6-2), a boss (1-2-6-3), a slot (1-2-6-4), a second slot hole (1-2-6-5) and a second wing plate (1-2-6-6); The concave pressure-bearing shell (1-2-2) is a hemispherical cavity, and first wing plates (1-2-2-1) are arranged at both ends of the maximum diameter of the cavity of the concave pressure-bearing shell (1-2-2), and a first slot hole (1-2-2-2) is arranged on the first wing plate (1-2-2-1). The outer wall surface of the cavity of the concave pressure-bearing shell (1-2-2) is provided with a first air outlet (1-2-2-3) and a first air inlet (1-2-2-4) with external threads, and the The convex pressure-bearing shell (1-2-6) is a hemispherical cavity, and second wing plates (1-2-6-6) are arranged at both ends of the maximum diameter of the cavity of the convex pressure-bearing shell (1-2-6), and a second slot hole (1-2-6-5) is arranged on the second wing plate (1-2-6-6). The cavity wall of the convex pressure-bearing shell (1-2-6) is provided with a notch (1-2-6-4) for installing a plate-shaped specimen and a boss (1-2-6-3) protruding from the diameter end face; The parallel length portion of the metal sample (1-2-1) is placed in the notch (1-2-6-4) of the convex pressure-bearing shell (1-2-6), the inner sealing gasket (1-2-3) is arranged on the second sealing end face (1-2-6-2), the outer sealing gasket (1-2-4) is arranged on the first sealing end face (1-2-6-1), the notch (1-2-6-4) is cast with sealing glue, the concave pressure-bearing shell (1-2-2) and the convex pressure-bearing shell (1-2-6) are pressed from both sides and fixed by bolts, and the extensometer (1-2-5) is installed on the sample (1-2-1) by a rubber band.

4. A high-pressure hydrogen environment mechanical properties detection device according to claim 3, characterized in that: The gas supply system comprises a first vortex flowmeter (2-1), a first medium delivery pipe (2-2), a first pressure reducing valve (2-3), an X gas bottle (2-4), a nitrogen bottle (2-5), a second pressure reducing valve (2-6), a second medium delivery pipe (2-7), a second vortex flowmeter (2-8), a third vortex flowmeter (2-9), a third medium delivery pipe (2-10), a third pressure reducing valve (2-11) and a hydrogen bottle (2-12); The X gas bottle (2-4), the nitrogen bottle (2-5) and the hydrogen bottle (2-12) are arranged in a row on a horizontal ground; the X gas bottle (2-4) is provided with a first pressure reducing valve (2-3); a first vortex flowmeter (2-1) is provided on the upper side of the first pressure reducing valve (2-3); the first pressure reducing valve (2-3) is connected to the air inlet of the first vortex flowmeter (2-1) through a first medium delivery pipe (2-2); the nitrogen bottle (2-5) is provided with a second pressure reducing valve (2-6); A second vortex flowmeter (2-8) is arranged on the upper side of (2-6); the second pressure reducing valve (2-6) is connected to the air inlet of the second vortex flowmeter (2-8) through a second medium delivery pipe (2-7); a third pressure reducing valve (2-11) is arranged on the hydrogen bottle (2-12); a third vortex flowmeter (2-9) is arranged on the upper side of the third pressure reducing valve (2-11); the third pressure reducing valve (2-11) is connected to the air inlet of the third vortex flowmeter (2-9) through a third medium delivery pipe (2-10).

5. A high-pressure hydrogen environment mechanical property detection device according to claim 4, characterized in that: The air outlet of the first vortex flowmeter (2-1) is connected to the Venturi mixer (10) via a ninth medium delivery pipe (11), and the air outlets of the second vortex flowmeter (2-8) and the third vortex flowmeter (2-9) are connected to the Venturi mixer (10) via a tenth medium delivery pipe (12).

6. A high-pressure hydrogen environment mechanical property detection device according to claim 5, characterized in that: The gas pressurization and detection system (3) comprises a gas purity analysis device (3-1), an exhaust gas treatment device (3-2), a fourth medium delivery pipe (3-3), a fifth medium delivery pipe (3-4), a water collecting tank (3-5), a table No. 1 (3-6), and a compressor (3-7); the gas purity analysis device (3-1) is arranged on the table No. 1 (3-6); the compressor (3-7) is arranged at the lower end of the table No. 1 (3-6); the exhaust gas treatment device (3-2) is placed at the highest point parallel to the gas purity analysis device (3-1); and the water collecting tank (3-5) is arranged on the horizontal ground on one side of the compressor (3-7); The gas purity analysis device (3-1) comprises a first data transmission port (3-1-1), a second air inlet (3-1-2), a drain port (3-1-3) and a second air outlet (3-1-4); the first data transmission port (3-1-1) is arranged on one side of the upper part of the gas purity analysis device (3-1); the second air inlet (3-1-2), the drain port (3-1-3) and the second air outlet (3-1-4) are arranged at the lower end of the gas purity analysis device (3-1); holes corresponding to the second air inlet (3-1-2), the drain port (3-1-3) and the second air outlet (3-1-4) are arranged on the table No. 1 (3-6); the drain port (3-1-3) is connected to the water collecting tank (3-5) through the fifth medium delivery pipe (3-4); and the second air outlet (3-1-4) is connected to the tail gas treatment device (3-2) through the fourth medium delivery pipe (3-3).

7. A high-pressure hydrogen environment mechanical property detection device according to claim 6, characterized in that: The air inlet of the compressor (3-7) is connected to the Venturi mixer (10) via a sixth medium delivery pipe (5), the air outlet of the compressor (3-7) is connected to the first air inlet (1-2-2-4) via an eighth medium delivery pipe (9), and the second air inlet (3-1-2) is connected to the first air outlet (1-2-2-3) via a seventh medium delivery pipe (8).

8. A high-pressure hydrogen environment mechanical property detection device according to claim 7, characterized in that: The computer-aided system (4) comprises a second table (4-1), a computer (4-2), and a data processor (4-3); the computer (4-2) and the data processor (4-3) are respectively arranged on the second table (4-1); the data processor (4-3) is provided with a second data transmission port (4-3-1) and a third data transmission port (4-3-2); the second data transmission port (4-3-1) is connected to the first data transmission port (3-1-1) via a first signal transmission line (6); and the third data transmission port (4-3-2) is connected to the data transmission interface (1-1-4) via a second signal transmission line (7).

9. A high-pressure hydrogen environment mechanical property detection device according to claim 8, characterized in that: The outer diameter of the inner sealing gasket (1-2-3) is consistent with the outer diameter of the boss (1-2-6-3), the inner diameter of the inner sealing gasket (1-2-3) is consistent with the inner diameter of the boss (1-2-6-3), and the inner diameter of the outer sealing gasket (1-2-4) is consistent with the outer diameter of the boss (1-2-6-3).

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