A method for improving the fatigue life of on-site hydrogen storage cylinders

Abstract

The present invention discloses a method for improving the fatigue life of on-site hydrogen storage cylinders, which comprises the following steps: 1) designing a self-reinforcement treatment system for hydrogen storage cylinders; 2) performing a self-reinforcement process treatment on the hydrogen storage cylinders through the self-reinforcement treatment system for hydrogen storage cylinders; 3) determining the self-reinforcement pressure range under different diameter ratios through finite element simulation and theoretical calculation; 4) finally determining the allowable number of cycles; 5) fitting an empirical formula for the optimal self-reinforcement pressure design for hydrogen storage cylinders under different diameter ratios; 6) comparing and verifying the optimal self-reinforcement pressure-diameter ratio curve. By performing a self-reinforcement process treatment on high-pressure seamless hydrogen storage steel cylinders, the present invention effectively improves the service life of the cylinders and reduces the difficulty of cylinder process forming.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-pressure seamless steel cylinder hydrogen storage, and particularly relates to a method for improving the fatigue life of hydrogen storage cylinders for stations. Background Art

[0002] As a secondary clean energy with high energy density and no pollution, hydrogen energy will play an important role in future economic and technological development. In recent years, with the development of new energy vehicles, the number of hydrogen refueling stations, as the infrastructure for providing hydrogen to fuel cell vehicles, has been increasing continuously. The entire hydrogen energy industry chain includes three key links: hydrogen production, hydrogen storage and transportation, and hydrogen energy utilization. In the development of hydrogen energy, the main challenge faced by China lies in the storage and transportation of hydrogen. At present, there are mainly 4 hydrogen storage technologies in China: high-pressure liquid hydrogen storage, cryogenic liquid hydrogen storage, organic liquid hydrogen storage, and solid material hydrogen storage. Among them, the high-pressure gaseous hydrogen storage technology is the most mature, but there are bottlenecks in the safety of hydrogen storage. In order to stabilize the existing hydrogen storage volume and improve the safety of hydrogen storage cylinders, ultra-high pressure container equipment has been widely used in the chemical and petroleum industries. For thick-walled gas cylinders, due to the thick wall and complex shape, the stress distribution is extremely uneven, and the inner wall stress is much higher than the outer wall, which easily enters the yield stage; in addition, due to the large size of the blank material, defects that are difficult to detect often occur in casting, forging, and heat treatment, posing a hidden danger of fatigue fracture failure. The existing hydrogen storage for stations is generally below 60 MPa, the steel cylinder is thick, and the manufacturing difficulty is great. 100 MPa is the development trend, and a greater thickness is required, making spin forming more difficult. Therefore, how to effectively reduce the operating cost, reduce the process difficulty, and increase the fatigue life of the equipment has become a problem to be solved in the project. While conducting theoretical analysis, how to implement the theoretical results also requires a comprehensive test plan. How to combine theoretical analysis and test process has become a problem to be solved in China's hydrogen storage technology industry, and it is an indispensable key link in the development and improvement of China's hydrogen storage technology. Summary of the Invention

[0003] In view of the above problems, the present invention provides a method for improving the fatigue life of hydrogen storage cylinders for stations, which solves the technical problems such as high cost, great preparation process difficulty, low fatigue life, and difficult test implementation caused by the large thickness of the steel cylinder in the prior art.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] A method for improving the fatigue life of hydrogen storage cylinders for stations includes the following steps:

[0006] 1) Design a self-reinforcement treatment system for hydrogen storage cylinders;

[0007] 2) Through the self-reinforcement treatment system for hydrogen storage cylinders, perform a self-reinforcement process treatment of pressurization - depressurization - pressurization on the hydrogen storage cylinders;

[0008] 3) Through numerical simulation and theoretical analysis, the self-reinforcement pressure - elastoplastic interface diameter curve P under different diameter ratios is obtained A -D P : The finite element simulation is mainly used to determine the range of self-reinforcement pressure that the gas cylinder can withstand. The specific index is that the residual strain along the wall thickness direction of the gas cylinder after unloading ≤ 2%; the theoretical analysis determines the range of self-reinforcement pressure under different diameter ratios by calculating the bursting pressure of the gas cylinder under different diameter ratios; the results of numerical simulation and theoretical analysis are compared to obtain the elastoplastic interface diameter D under different diameter ratios and different self-reinforcement pressures P ;

[0009] 4) Combine the self-reinforcement technology with the fracture mechanics theory. Assume that there are initial defects on the inner wall of the gas cylinder, and calculate the circumferential residual stress distribution σ along the wall thickness direction of the gas cylinder after self-reinforcement treatment by combining the elastoplastic interface diameter data obtained in 3) tRA , fit the stress distribution along the wall thickness direction of the hydrogen gas cylinder to obtain the stress distribution coefficient A i , calculate the stress intensity factor K IC and the crack growth rate da / dN, and obtain the corresponding number of cycles N when the crack propagates to the crack size P , and finally determine the allowable number of cycles N; the specific formula is as follows:

[0010] After the self-reinforcement pressure is unloaded, calculate the circumferential residual stress:

[0011] When D i ≤D≤D P :

[0012]

[0013] When D P ≤D≤D0:

[0014]

[0015] Fit the above circumferential residual stress distribution, and calculate the residual stress intensity factor:

[0016]

[0017] Calculate the fatigue crack growth rate:

[0018]

[0019] During the crack propagation process, when the maximum stress intensity factor K max is equal to the fracture toughness K IC , the crack propagates to the critical size, and the corresponding number of cycles N is obtained c; According to fracture mechanics theory, select N c / 2 and 0.75a0 + 0.25a obtained by curve fitting c corresponding cycle number N P中 of the smaller value as the allowable cycle number N; where a0 represents the initial crack depth and a c represents the critical crack depth;

[0020] 5) Through steps 3) and 4), for hydrogen storage cylinders under different diameter ratios, different autofrettage pressure conditions are proposed according to the autofrettage pressure - diameter ratio curve, and an empirical formula for the best autofrettage pressure design is obtained by fitting.

[0021] 6) Compare and verify the best autofrettage pressure - diameter ratio curve.

[0022] Furthermore, the specific steps of step 2) are as follows:

[0023] 2.1) Apply an enhanced pressure to the hydrogen storage cylinder to pressurize it, causing local yielding of the inner wall of the cylinder;

[0024] 2.2) Release the pressure of the hydrogen storage cylinder. The yielding area is squeezed by the elastic area due to its inability to return to its original state, generating residual compressive stress. Correspondingly, residual tensile stress is generated in the elastic area;

[0025] 2.3) Apply a working pressure to the hydrogen storage cylinder to pressurize it. The residual tensile stress generated by the working pressure cancels out the residual compressive stress in the yielding area and superimposes with the residual tensile stress in the elastic area, making the overall stress level of the cylinder average, reducing the stress intensity factor level, thereby reducing the crack propagation rate and increasing the allowable cycle number of the cylinder, i.e., the fatigue life.

[0026] Furthermore, the hydrogen storage cylinder autofrettage treatment system in step 1) includes a hydrogen source storage container A, a hydrogen source storage container B, a hydrogen source storage container C, a gas compressor, a three - way valve A, a three - way valve B, and a test high - pressure seamless hydrogen storage cylinder. The hydrogen source storage container A is connected to the gas compressor through a connecting pipeline. The gas compressor is connected to the hydrogen source storage container B and the test high - pressure seamless hydrogen storage cylinder respectively through the three - way valve A by connecting pipelines. A three - way valve B is provided on the connecting pipeline between the three - way valve A and the test high - pressure seamless hydrogen storage cylinder, and is connected to the test high - pressure seamless hydrogen storage cylinder and the hydrogen source storage container C respectively through the three - way valve B by connecting pipelines.

[0027] Furthermore, a temperature controller is provided in the hydrogen source storage container A to ensure a constant temperature at normal temperature; a flow regulating valve is provided on the connecting pipeline between the hydrogen source storage container A and the gas compressor.

[0028] Further, the test high-pressure seamless hydrogen storage cylinder is placed in a blasting pit to prevent the cylinder from rupturing due to excessive pressure.

[0029] Further, a pressure transmitter is provided between the three-way valve B and the pipeline connecting the test high-pressure seamless hydrogen storage cylinder.

[0030] Further, a pressure gauge is provided on the gas compressor.

[0031] Further, the test high-pressure seamless hydrogen storage cylinder includes a cylinder body and a bottle mouth valve connected to the upper end of the cylinder body. The left and right ends of the bottle mouth valve are respectively connected to a precision pressure gauge and a pressure counter. A flow regulating valve is provided between the precision pressure gauge and the bottle mouth valve.

[0032] Further, the bottle mouth valve mainly includes a valve body, a plug, a plug rod, a screw sleeve, a wrench and a nut; the plug is placed inside the valve body, and holes are opened at the same position of the valve body to form device connection hole A and device connection hole B. The plug is fixedly connected to the plug rod and connected to the valve body through the screw sleeve. The wrench is fixed to the plug rod through the screw sleeve and the nut. The rotation of the plug is controlled by turning the wrench to control the gas inlet and outlet.

[0033] Further, the test process of the hydrogen storage cylinder autofrettage treatment system is as follows:

[0034] The hydrogen in the hydrogen source storage container is transported to the gas compressor through the flow regulating valve between the hydrogen source storage container and the gas compressor for pressurization. When the system pressure exceeds the specified value, the three-way valve A and the three-way valve B are opened, and the overflow gas is transported back to the hydrogen source storage container. After the gas is compressed, it is introduced into the test high-pressure seamless hydrogen storage cylinder. The pressure inside the cylinder is observed through the precision pressure gauge. The pressure is converted into an electric signal through the pressure transmitter on the pipeline connecting the three-way valve B and the test high-pressure seamless hydrogen storage cylinder and transmitted to the pressure counter for recording and measurement. After the test is completed, the gas in the cylinder is discharged into the hydrogen source storage container.

[0035] By adopting the above technology, compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1) In the present invention, by performing autofrettage treatment on the high-pressure seamless hydrogen storage steel cylinder, the service life of the cylinder is effectively improved, and the difficulty of the cylinder process forming is reduced;

[0037] 2) In the present invention, by curve fitting the optimal autofrettage pressure under different diameter ratios, the optimal autofrettage pressure curve is obtained;

[0038] 3) In the present invention, through the entire set of test processes, the optimal autofrettage pressure calculated theoretically can be reasonably verified;

[0039] 4) In the present invention, the test high-pressure seamless steel cylinder is reasonably designed. The bottle mouth valve can precisely control the inflow and outflow of gas by rotating a wrench, and is respectively connected to a precision pressure gauge and a pressure counter at both ends. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic flow chart of the autofrettage process test of the present invention;

[0041] Figure 2 is a schematic diagram of the autofrettage principle of the present invention;

[0042] Figure 3 is a curve of the autofrettage pressure range at different diameter ratios of the present invention;

[0043] Figure 4 is an a-N curve of fatigue crack propagation under different diameter ratios at a high stress ratio of the present invention;

[0044] Figure 5 is a graph of the optimal autofrettage pressure - diameter ratio of the present invention;

[0045] Figure 6 is an overall schematic diagram of the high-pressure seamless steel cylinder of the present invention;

[0046] Figure 7 is a schematic diagram of the bottle mouth valve of the high-pressure seamless steel cylinder of the present invention;

[0047] In the figure: 1. Hydrogen source storage container A; 101 Hydrogen source storage container B, 102 Hydrogen source storage container C, 2. Temperature controller; 3. Flow regulating valve; 4. Gas compressor; 5. Pressure gauge; 6. Connecting pipe; 7. Precision pressure gauge; 8. Pressure transmitter; 9. Three-way valve B; 10. Test high-pressure seamless hydrogen storage cylinder; 11. Pressure counter; 12. Blasting pit; 13. Bottle mouth valve; 1301. Valve body; 1302. Plug; 1303. Plug rod; 1304. Nut sleeve; 1305. Wrench; 1306. Nut; 1307 Connection hole A, 1308 Device connection hole B; 14. Three-way valve A. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0049] As Figure 1As shown in the figure, the test process includes a hydrogen source storage container 1, a temperature controller 2, a flow regulating valve 3, a gas compressor 4, a pressure gauge 5, a connecting pipe 6, a precision pressure gauge 7, a pressure transmitter 8, a three-way valve B9, a test high-pressure seamless hydrogen storage cylinder 10, a pressure counter 11, a blasting pit 12, and a three-way valve A14. The test process transports the hydrogen in the hydrogen source storage container 1 to the gas compressor 4 through the flow regulating valve 3 and the connecting pipe 6 for pressurization. When the system pressure exceeds the specified value, the three-way valve A14 and the three-way valve B9 are opened to transport the overflow gas back to the hydrogen source storage container 101. After the gas is compressed, it is introduced into the test high-pressure seamless hydrogen storage cylinder 10. The pressure inside the cylinder is observed through the precision pressure gauge 7. A pressure transmitter 8 is set between the connecting pipe of the three-way valve B9 and the test high-pressure seamless hydrogen storage cylinder 10. The pressure is converted into an electric signal by the pressure transmitter 8 and transmitted to the pressure counter 11 for recording and measurement. After the test is completed, the gas in the cylinder is discharged into the hydrogen source storage container 102. At the same time, a temperature controller 2 is set in the hydrogen source storage container 1 to ensure that the temperature is constant and at room temperature. The test high-pressure seamless hydrogen storage cylinder 10 is placed in the blasting pit 12 to prevent the gas cylinder from bursting due to excessive pressure.

[0050] As Figure 2 , as shown in Figure 3, by subjecting the gas cylinder with a thickness of t to autofrettage treatment, local yielding occurs on the inner wall of the gas cylinder, dividing the entire gas cylinder into a plastic region (D i / 2 ≤ r ≤ D p / 2) and an elastic region (D p / 2 ≤ r ≤ D0 / 2). Through finite element simulation and theoretical calculation, the autofrettage pressure P A ——the diameter D of the elastic-plastic interface P curve is obtained, thereby determining the autofrettage pressure range under different diameter ratios k.

[0051] As Figure 4 shown, combined with Figure 3 the autofrettage pressure P A ——the diameter D of the elastic-plastic interface P curve, after unloading, the yield region is squeezed by the elastic region due to its inability to return to its original state, generating residual compressive stress. Correspondingly, residual tensile stress is generated in the elastic region. After introducing the working pressure, the residual tensile stress generated by the working pressure cancels out the residual compressive stress in the yield region and superimposes with the residual tensile stress in the elastic region, making the overall stress level of the gas cylinder average, reducing the stress intensity factor level, thereby reducing the crack propagation rate, increasing the allowable cycle number of the gas cylinder, i.e., the fatigue life, reducing the process difficulty, and lowering the process cost.

[0052] As Figure 5 shown, through Figure 4The calculation results are fitted to obtain the best autofrettage pressure-diameter ratio curve; to ensure the safety of the gas cylinder during the test, the diameter ratio of the gas cylinder is 1.3 - 1.4; if the thickness is too small, there are potential safety hazards, if the thickness is too large, the spinning process is difficult, and the autofrettage effect is small.

[0053] As Figure 6 , as shown in Fig. 7, the high-pressure seamless hydrogen storage gas cylinder 10 for the test includes two parts: a cylinder body and a bottle mouth valve 13. The bottle mouth valve is similar to a three-way structure, with the lower end connected to the cylinder body, and the left and right ends connected to a precision pressure gauge 7 and a pressure counter 11. A flow regulating valve 3 is provided between the precision pressure gauge 7 and the valve body 1301, and it is connected to other devices through a connecting pipe 6. The bottle mouth valve mainly includes a valve body 1301, a plug 1302, a plug rod 1303, a screw sleeve 1304, a wrench 1305 and a nut 1306. The plug 1302 is placed inside the valve body 1301, and holes are opened at the same position as the device connection hole A1307 and the device connection hole B1308; the plug 1302 is fixedly connected to the plug rod 1303 and is connected to the valve body 1301 through the screw sleeve 1304. The wrench 1305 is fixed to the plug rod 1303 through the screw sleeve 1304 and the nut 1306. By rotating the wrench 1305, the rotation of the plug 1302 is controlled to control the gas inlet and outlet.

[0054] The present invention proposes to improve the fatigue life of hydrogen storage gas cylinders for hydrogen refueling stations through the autofrettage technology process. The autofrettage pressure of the hydrogen storage gas cylinder is designed according to GB / T34019-2017. The fatigue crack growth of hydrogen storage gas cylinders under different diameter ratios is analyzed. The best autofrettage pressure is determined based on the allowable number of cycles obtained from the calculation results and the potential safety hazards and actual situations to be considered in actual engineering applications, and the diameter ratio - best autofrettage pressure curve is obtained. The entire test process gives the test method and process of the hydrogen storage gas cylinder, stipulates the basic requirements of the device, the operation method and the operation key points. The best autofrettage pressure is verified through the test to ensure the rationality of the autofrettage pressure and effectively improve the service life of the hydrogen storage gas cylinder.

Claims

1. A method for improving the fatigue life of hydrogen storage cylinders for stations, characterized in that, It includes the following steps: 1) Design a self-reinforcement treatment system for hydrogen storage cylinders; 2) Through the self-reinforcement treatment system for hydrogen storage cylinders, perform a self-reinforcement process of pressurization - depressurization - pressurization on the hydrogen storage cylinders; 3) Through numerical simulation and theoretical analysis, the autofrettage pressure - elastic - plastic interface diameter curve under different diameter - ratio conditions is obtained: Numerical simulation is used to determine the range of autofrettage pressure that the gas cylinder can withstand, and the specific index is that the residual strain along the wall thickness direction of the gas cylinder after unloading ≤ 2%; Theoretical analysis determines the range of autofrettage pressure under different diameter - ratio conditions by calculating the burst pressure of the gas cylinder under different diameter - ratio conditions; Comparing the results of numerical simulation and theoretical analysis, the elastic - plastic interface diameter D under different diameter - ratios and different autofrettage pressures is obtained P ; 4) Combine the autofrettage technique with the fracture mechanics theory. Assume there are initial defects on the inner wall of the gas cylinder, and combine with the elastoplastic interface diameter D obtained in step 3) P to calculate the circumferential residual stress distribution σ in the wall thickness direction of the gas cylinder after autofrettage treatment tRA , fit the stress distribution coefficient A by fitting the stress distribution in the wall thickness direction of the hydrogen gas cylinder i , calculate the stress intensity factor K and the crack growth rate da / dN, and obtain the corresponding number of cycles N when the crack propagates to the crack size P and N c , and finally determine the allowable number of cycles N; the specific formula is as follows: After the self-reinforcement pressure is unloaded, calculate the circumferential residual stress: When D i ≤ D ≤ D P : When D P ≤ D ≤ D0: D0 represents the outer diameter of the gas cylinder, R P0.2 represents the yield strength of the material, F b represents the correction factor, D i represents the inner diameter of the gas cylinder; Fitting the above circumferential residual stress distribution, the residual stress intensity factor K is calculated Ires : A i ' are four fitting coefficients obtained by fitting the circumferential residual stress distribution, G i are four surface correction coefficients when calculating the stress intensity factor, obtained by linear interpolation, and is a dynamic value that changes with the crack depth; a is the crack depth, l is the crack length, and Q is the crack shape factor; Calculate the fatigue crack growth rate: C is the fatigue crack growth rate coefficient, and R k represents the ratio of the minimum stress intensity factor to the maximum stress intensity factor, and ΔK represents the stress intensity factor range; 5) Through steps 3) and 4), for hydrogen storage cylinders with different diameter ratios, obtain different self-reinforcement pressure conditions for different diameter ratios through the self-reinforcement pressure - diameter ratio curve, and fit to obtain an empirical formula for the optimal self-reinforcement pressure design; 6) Conduct a comparative verification on the optimal self-reinforcement pressure - diameter ratio curve.

2. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 1, characterized in that, The specific steps of step 2) are as follows: 2.1) Introduce an enhanced pressure to pressurize the hydrogen storage cylinder, causing local yielding of the inner wall of the cylinder; 2.2) Depressurize the hydrogen storage cylinder. The yielded area is extruded by the elastic area due to its inability to return to its original state, generating a residual compressive stress. Correspondingly, a residual tensile stress is generated in the elastic area; 2.3) Introduce the working pressure to pressurize the hydrogen storage cylinder. The residual tensile stress generated by the working pressure cancels out the residual compressive stress in the yielded area and superimposes with the residual tensile stress in the elastic area, making the overall stress level of the cylinder average, reducing the stress intensity factor level, thereby reducing the crack growth rate and increasing the allowable cycle number of the cylinder, i.e., the fatigue life.

3. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 1, characterized in that, In step 1), the self-reinforcement treatment system for hydrogen storage cylinders includes a hydrogen source storage container A (1), a hydrogen source storage container B (101), a hydrogen source storage container C (102), a gas compressor (4), a three-way valve A (14), a three-way valve B (9), and a test high-pressure seamless hydrogen storage cylinder (10). The hydrogen source storage container A (1) is connected to the gas compressor (4) through a connecting pipe (6). The gas compressor (4) is connected to the hydrogen source storage container B (101) and the test high-pressure seamless hydrogen storage cylinder (10) respectively through a three-way valve A (14) via a connecting pipe (6). A three-way valve B (9) is arranged on the connecting pipe (6) between the three-way valve A (14) and the test high-pressure seamless hydrogen storage cylinder (10), and is connected to the test high-pressure seamless hydrogen storage cylinder (10) and the hydrogen source storage container C (102) respectively through a connecting pipe (6) via the three-way valve B (9).

4. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 3, characterized in that, A temperature controller (2) is arranged in the hydrogen source storage container A (1) to ensure a constant temperature at normal temperature; a flow regulating valve (3) is arranged on the connecting pipe (6) between the hydrogen source storage container A (1) and the gas compressor (4).

5. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 3, characterized in that, The test high-pressure seamless hydrogen storage cylinder (10) is placed in a blasting pit (12) to prevent the cylinder from bursting due to excessive pressure.

6. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 3, characterized in that, A pressure transmitter (8) is arranged between the three-way valve B and the connecting pipe of the test high-pressure seamless hydrogen storage cylinder (10).

7. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 3, characterized in that, A pressure gauge (5) is arranged on the gas compressor (4).

8. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 3, characterized in that, The test high-pressure seamless hydrogen storage cylinder (10) includes a cylinder body and a bottle mouth valve (13) connected to the upper end of the cylinder body. Precision pressure gauges (7) and a pressure counter (11) are respectively connected to the left and right ends of the bottle mouth valve (13). A flow regulating valve (3) is arranged between the precision pressure gauge (7) and the bottle mouth valve (13).

9. A method for improving the fatigue life of on-site hydrogen storage cylinders according to claim 8, characterized in that The bottle mouth valve mainly includes a valve body (1301), a plug (1302), a plug rod (1303), a screw sleeve (1304), a wrench (1305) and a nut (1306); the plug (1302) is placed inside the valve body (1301), and holes are opened at the same position of the valve body (1301) to form a device connection hole A (1307) and a device connection hole B (1308). The plug (1302) is fixedly connected to the plug rod (1303) and connected to the valve body (1301) through the screw sleeve (1304). The wrench (1305) is fixed on the plug rod (1303) through the screw sleeve (1304) and the nut (1306). By rotating the wrench (1305), the rotation of the plug (1302) is controlled to control the gas inlet and outlet.

10. A method for improving the fatigue life of on-site hydrogen storage cylinders according to any one of claims 1-9, characterized in that, The test process of the hydrogen storage cylinder self-reinforcement treatment system is as follows: Hydrogen in the hydrogen source storage container A (1) is transported to the gas compressor (4) for pressurization through the flow regulating valve (3) between the hydrogen source storage container A (1) and the gas compressor (4). When the system pressure exceeds the specified value, the three-way valve A (14) and the three-way valve B (9) are opened, and the overflow gas is transported back to the hydrogen source storage container B (101). After the gas is compressed, it is introduced into the test high-pressure seamless hydrogen storage cylinder (10). The pressure in the cylinder is observed through the precision pressure gauge (7). The pressure transmitter (8) on the connecting pipe (6) between the three-way valve B (9) and the test high-pressure seamless hydrogen storage cylinder (10) converts the pressure into an electric signal and transmits it to the pressure counter (11) for recording and measurement. After the test is completed, the gas in the cylinder is discharged into the hydrogen source storage container C (102).

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