Comprehensive test device for high-pressure hydrogen storage pressure vessel

Abstract

The invention relates to the technical field of test devices, in particular to a high-pressure hydrogen storage pressure vessel comprehensive test device which comprises a water supply system, a gas supply system, a driving device, a pressure relief system, a storage tank, a data acquisition and video monitoring system and a control system. The water supply system and the gas supply system are respectively communicated with a gas liquid inlet of the storage tank, and the pressure relief system is connected with the water supply system and is used for relieving pressure of liquid in the storage tank; the driving device is connected with the air supply system; and the data acquisition and video monitoring system is used for monitoring data of the storage tank and is electrically connected with the control system. According to the invention, the structural stability of the storage tank under the overload condition can be tested; the fatigue life and the cycle durability of the storage tank can be evaluated; the ultimate bearing capacity and the failure mode of the storage tank can be measured; and the sealing performance of the storage tank under the high-pressure gas medium is verified.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of test devices, in particular to a high-pressure hydrogen storage pressure vessel comprehensive test device. BACKGROUND

[0002] High-pressure gaseous hydrogen storage is the most mature and widely used hydrogen storage method. The structural integrity and fatigue resistance of high-pressure hydrogen storage vessels are the core prerequisites for ensuring the safe operation of hydrogen energy systems. Before leaving the factory, hydrogen storage vessels need to undergo a series of performance tests, including water pressure tests to check their structural strength, pressure cycle tests to check their fatigue life, and water pressure burst tests to determine their pressure limit. In addition, hydrogen storage vessels must pass airtightness tests to verify their sealing reliability under high-pressure gas conditions and ensure no leakage risk. Currently, water pressure testing machines, pressure cycle testing machines, water pressure burst testing machines, and airtightness testing machines are often purchased separately, which is costly.

[0003] Based on the above problems, the present application provides a high-pressure hydrogen storage pressure vessel comprehensive test device. SUMMARY

[0004] The present application aims to overcome the shortcomings of the prior art and provide a high-pressure hydrogen storage pressure vessel comprehensive test device. The present application uses a water supply system to inject water into the storage tank and pressurize it to a predetermined pressure value, and maintains this pressure for a period of time. Observing and recording whether the container has any leakage or deformation phenomenon can complete the water pressure test of the storage tank, ensuring its structural stability under overload conditions. The control system controls the water supply system and the pressure relief system to repeatedly pressurize and depressurize the storage tank, simulating the pressure changes in the actual use of the storage tank, evaluating the fatigue strength of the storage tank, and completing the pressure cycle test of the storage tank, thereby evaluating the fatigue life and cycle durability of the storage tank. The booster pump in the water supply system gradually pressurizes the test storage tank until the storage tank ruptures, and the limit pressure value is recorded, which can complete the water pressure burst test, thereby determining the ultimate bearing capacity and failure mode of the storage tank. The gas booster pump of the gas supply system fills nitrogen into the storage tank to detect the sealing performance of the storage tank under a certain pressure, and verifies that the storage tank has no gas leakage, which can complete the airtightness test of the storage tank, thereby verifying the sealing performance of the storage tank under high-pressure gas medium.

[0005] To achieve the purpose of the present application, the technical solution adopted by the present application is as follows: The application discloses a kind of high-pressure hydrogen storage pressure vessel comprehensive test device, including water supply system, gas supply system, driving device, pressure relief system, storage tank, data acquisition and video monitoring system and control system, one end of the storage tank is equipped with storage tank inlet liquid port, the water supply system and gas supply system are communicated with the storage tank inlet liquid port respectively, the pressure relief system is connected with the water supply system, for the liquid in storage tank is relieved pressure;The driving device is connected with the gas supply system, for driving gas booster pump in gas supply system;The data acquisition and video monitoring system are used to monitor the data of storage tank, and the data acquisition and video monitoring system are electrically connected with control system.

[0006] The water supply system includes a water source, a low-pressure pump, a water tank, a booster pump, and a pressure maintaining valve. The input end of the low-pressure pump is connected with the water source. The output end of the low-pressure pump is connected with the input end of a water supply tee pipe. The first output end of the water supply tee pipe is communicated with the storage tank inlet liquid port of the storage tank through a first water supply pipeline. A first water supply stop valve is arranged on the first water supply pipeline. The second output end of the water supply tee pipe is communicated with the storage tank inlet liquid port through a second water supply pipeline. A second water supply stop valve, a water tank, a third water supply stop valve, a booster pump, and a pressure maintaining valve are sequentially connected on the second water supply pipeline.

[0007] A filter is arranged between the low-pressure pump and the water source, between the second water supply stop valve and the second output end of the water supply tee pipe, and between the third water supply stop valve and the water tank. A liquid level sensor is arranged in the water tank. A check valve is arranged between the booster pump and the pressure maintaining valve.

[0008] The booster pump is a high-pressure three-plunger pump.

[0009] The gas supply system includes a gas source, a first gas tee, a gas booster pump, and a pressure gauge. The input end of the first gas tee is connected with the gas source through a gas supply stop valve. The output end of the first gas tee is connected with the input end of a gas supply tee pipe. The first output end of the gas supply tee pipe is connected with the storage tank inlet liquid port through a first gas supply pipeline. A first needle valve and a pressure gauge are arranged on the first gas supply pipeline. The second output end of the gas supply tee pipe is connected with the storage tank inlet liquid port through a second gas supply pipeline. A second needle valve, a gas booster pump, and a pressure gauge are sequentially arranged on the second gas supply pipeline.

[0010] A safety valve is arranged between the gas booster pump and the pressure gauge on the second gas supply pipeline.

[0011] The driving device includes an air compressor, an air storage tank, a second gas tee, and an electromagnetic valve. The gas booster pump is driven by compressed air of the air compressor. The air storage tank, the second gas tee, and the electromagnetic valve are sequentially connected between the air compressor and the gas booster pump.

[0012] The pressure relief system comprises a first pressure relief valve, a second pressure relief valve, a manual pressure relief valve, a safety overflow valve and a lower limit pressure regulating device, one end of the first pressure relief valve, the second pressure relief valve, the manual pressure relief valve and the safety overflow valve is communicated with the second water supply pipeline respectively, and the other end is connected with the water source; the lower limit pressure regulating device comprises a lower limit pressure sensor, a PLC controller and a digital display meter, the lower limit pressure sensor is communicated with the second water supply pipeline, and the lower limit pressure sensor, the digital display meter and the PLC controller are electrically connected.

[0013] The data acquisition and video monitoring system comprises a stress and strain monitoring unit, a temperature monitoring unit, a pressure monitoring unit and a high frame rate camera, the temperature monitoring unit and the pressure monitoring unit are communicated with the inner cavity of the storage tank respectively; the stress and strain monitoring unit is an optical fiber grating sensor embedded on the outer wall of the storage tank; the high frame rate camera is arranged above the storage tank and used for observing the state of the storage tank.

[0014] The control system comprises a PLC controller, an A / D signal conversion module and a D / A signal conversion module, the stress and strain monitoring unit, the temperature monitoring unit and the pressure monitoring unit transmit the collected analog signals to the PLC controller in the form of digital signals through the A / D signal conversion module, and the PLC controller converts the received digital signals into analog signals through the D / A signal conversion module, so as to control the actuator.

[0015] The beneficial effects of the present application are as follows: (1) The present application can complete the water pressure test of the storage tank by injecting water into the storage tank through the water supply system to pressurize to a predetermined pressure value and keeping the pressure for a period of time, observing and recording whether the container has leakage or deformation phenomenon, so as to ensure the structural stability of the storage tank under overload conditions; the pressure cycle test of the storage tank can be completed by controlling the water supply system and the pressure relief system to repeatedly pressurize and depressurize the storage tank, simulating the pressure change in the actual use of the storage tank, evaluating the fatigue strength of the storage tank, so as to evaluate the fatigue life and cycle durability of the storage tank; the water pressure burst test can be completed by gradually pressurizing the test storage tank through the booster pump in the water supply system until the storage tank breaks, recording the limit pressure value, so as to determine the limit bearing capacity and failure mode of the storage tank; the gas tightness test of the storage tank can be completed by filling nitrogen into the storage tank through the gas booster pump of the gas supply system, detecting the sealing performance of the storage tank under a certain pressure, verifying that the storage tank has no gas leakage, so as to verify the sealing performance of the storage tank under high pressure gas medium. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a flow chart of the test system of the present application; Figure 2 It is a flow chart of the water supply system in the present application; Figure 3Flow chart of the water supply system and driving device in the application; Figure 4 Flow chart of the pressure relief system in the application; Figure 5 Schematic diagram of the stress and strain monitoring unit in the application; Figure 6 Principle diagram of the control system in the application; Figure 7 Flow chart of the valve controlled by the PLC controller in the application; Figure 8 Flow chart of the water pressure test in the application; Figure 9 Flow chart of the pressure cycle test in the application; Figure 10 Flow chart of the water pressure burst test in the application; Figure 11 Flow chart of the air tightness test in the application.

[0017] In the figure: 100 water supply system, 101 water source, 102 low-pressure pump, 103 water tank, 104 booster pump, 105 pressure retaining valve, 106 filter, 107 check valve, 108 first water supply channel, 109 second water supply channel, 110 first water supply stop valve, 111 second water supply stop valve, 112 third water supply stop valve, 113 water supply tee pipe; 200 gas supply system, 201 gas source, 202 first gas tee, 203 gas booster pump, 204 pressure gauge, 205 gas supply stop valve, 206 gas supply tee pipe, 207 first gas supply pipeline, 208 second gas supply pipeline, 209 first needle valve, 210 second needle valve, 211 safety valve; 300 driving device, 301 air compressor, 302 gas storage tank, 303 second gas tee, 304 electromagnetic valve; 400 pressure relief system, 401 first pressure relief valve, 402 second pressure relief valve, 403 manual pressure relief valve, 404 safety overflow valve, 405 lower limit pressure adjusting device; 500 storage tank, 501 storage tank air inlet; 600 data acquisition and video monitoring system, 601 high-frame-rate camera; 700 control system, 701 PLC controller, 702 A / D signal conversion module, 703 D / A signal conversion module. DETAILED DESCRIPTION

[0018] The application is further described as follows: Please refer to Figures 1-11 , The application discloses a high-pressure hydrogen storage pressure container comprehensive test device, like Figures 1-4As shown, including water supply system 100, gas supply system 200, drive device 300, pressure relief system 400, storage tank 500, data acquisition and video monitoring system 600 and control system 700, one end of the storage tank 500 is provided with a storage tank gas inlet liquid port 501, the water supply system 100 and gas supply system 200 are communicated with the storage tank gas inlet liquid port 501 respectively, the pressure relief system 400 is connected with the water supply system 100, for the liquid in the storage tank 500 is relieved; the drive device 300 is connected with the gas supply system 200, for driving the gas booster pump 203 in the gas supply system 200; the data acquisition and video monitoring system 600 is used for monitoring the data of the storage tank 500, the data acquisition and video monitoring system 600 is electrically connected with the control system 700, the present application is through the water supply system 100 to the storage tank 500 in water injection pressurization to predetermined pressure value, and keep the pressure for a period of time, observe and record whether the container has leakage or deformation phenomenon, namely the water pressure test of the storage tank can be completed, to ensure its structural stability under overload condition; through the control system 700 controls the water supply system 100 and pressure relief system 400 to the storage tank 500 repeatedly pressurized and pressure relief operation, simulate the pressure change in the actual use of the storage tank 500, evaluate the fatigue strength of the storage tank 500, namely the pressure cycle test of the storage tank can be completed, thereby evaluating the fatigue life and cycle durability of the storage tank; through the booster pump in the water supply system 100 to the test storage tank 500 gradually pressurized, until the storage tank 500 occurs rupture, record the limit pressure value, namely the water pressure blasting test can be completed, thereby determining the ultimate bearing capacity and failure mode of the storage tank; through the gas booster pump of the gas supply system 200 fills nitrogen in the storage tank 500, detects the sealing performance of the storage tank 500 under certain pressure, verifies that the storage tank 500 has no gas leakage, namely the gas tightness test of the storage tank can be completed, thereby verifying the sealing performance of the storage tank under high pressure gas medium; the storage tank 500 is used as a hydrogen storage pressure vessel in the application.

[0019] Further, as Figure 2As shown, the water supply system can stably provide clean water for the experimental system, and the water supply system 100 comprises a water source 101, a low-pressure pump 102, a water tank 103, a booster pump 104, and a pressure maintaining valve 105. The input end of the low-pressure pump 102 is connected with the water source 101, and the output end of the low-pressure pump 102 is connected with the input end of a water supply tee pipe 113. The first output end of the water supply tee pipe 113 is connected with the tank inlet liquid port 501 of the storage tank 500 through a first water supply pipeline 108, and the first water supply pipeline 108 is provided with a first water supply stop valve 110. The second output end of the water supply tee pipe is connected with the tank inlet liquid port 501 through a second water supply pipeline 109, and the second water supply pipeline 109 is sequentially connected with a second water supply stop valve 111, the water tank 103, a third water supply stop valve 112, the booster pump 104, and the pressure maintaining valve 105. Considering that the volume of the hydrogen storage container to be tested in the project is large, in order to shorten the preparation time of the test, a large-flow centrifugal pump needs to be prepared to pre-charge the test container, and at the same time, the water tank 103 is cooled and watered. Considering that the volume of the tank 500 to be tested is large, if the booster pump 104 is directly used for water injection, it will cause insufficient flow and high energy consumption, resulting in energy waste. In order to reduce the water injection time, a low-pressure pump 102 with low pressure and large flow is needed to pre-charge and pre-pressurize the tank 500, and then the booster pump 104 is used for accurate pressurization. At the same time, the low-pressure pump 102 can also supply water to the water tank 103. The low-pressure pump 102 adopts frequency conversion control, which can adjust the flow according to the actual demand to ensure that the water injection process is stable and efficient. In addition, the water tank 102 is provided with a liquid level sensor for real-time monitoring of the water level change. The liquid level sensor and the second water supply stop valve 111 are respectively connected with a PLC controller 701, and the second water supply stop valve 111 is automatically opened and closed through the PLC controller 701, so as to realize automatic water replenishment of the water tank 102 and avoid affecting the test due to low water level.

[0020] Further, filters 106 are arranged between the low-pressure pump 102 and the water source 101, between the second water supply stop valve 111 and the second output end of the water supply tee pipe 113, and between the third water supply stop valve 112 and the water tank 103. According to the water quality requirements of GB / T 9251-2022 “Gas Cylinder Water Pressure Test Method”, the chlorine ion content of the water is not more than 25 mg / L. The temperature of the test water is not less than 5℃. Considering that the water source may contain impurities and particles, long-time operation will cause damage to the high-pressure pump and the pressure maintaining valve. Therefore, the filter 106 is arranged to improve the service life of the booster pump 104 and the valve. A check valve 107 is arranged between the booster pump 104 and the pressure maintaining valve 105, which is used to prevent the medium from flowing back during the pressurization process.

[0021] Further, the booster pump 104 is a high-pressure three-plunger pump, and the booster system is the core of the entire test device. The booster system is used to increase the pressure of the medium and effectively control the pressure and flow. When selecting, the maximum working pressure, flow range and response speed should be considered to ensure that it matches the test requirements.

[0022] According to the structure of the test pressure vessel, there are certain requirements for the cycle frequency when performing pressure cycle test. The water compression coefficient, tank volume expansion rate and pressure cycle frequency should be considered for selection. After comprehensive economic and practicality analysis, a high-pressure three-plunger pump with an output pressure of 150 MPa and a flow of 25 L / min is used as the water test booster device, which can meet the various working conditions of the test.

[0023] Further, as shown in Figure 3 , further explore the sealing of the test tank. After a series of water pressure medium tests, it is necessary to use gas as the pressure medium for the air tightness test. Nitrogen is non-flammable and low in price, which is suitable as a substitute for hydrogen medium. The gas supply system 200 includes a gas source 201, a first gas three-way joint 202, a gas booster pump 203 and a pressure gauge 204. The input end of the first gas three-way joint 202 is connected to the gas source 201 through a gas supply stop valve 205. The output end of the first gas three-way joint 202 is connected to the input end of the gas supply three-way pipe 206. The first output end of the gas supply three-way pipe 206 is connected to the tank inlet liquid port 501 through the first gas supply pipeline 207. The first gas supply pipeline 207 is provided with a first needle valve 209 and a pressure gauge 204. The second output end of the gas supply three-way pipe 206 is connected to the tank inlet liquid port 501 through the second gas supply pipeline 208. The second gas supply pipeline 208 is sequentially provided with a second needle valve 210, a gas booster pump 203 and a pressure gauge 204. The gas booster pump 203 is a pneumatic booster pump, which uses compressed air with a pressure of ≤0.7 MPa as the power source of the booster pump. The gas supply pipeline adopts multi-parallel connection. The first gas supply pipeline 207 is directly connected to the tank inlet liquid port 501 of the test tank 500. The gas source 201 can be directly connected to the test tank 500 through the first needle valve 209, which can quickly inject nitrogen into the tank 500 and play a role in purging and pre-charging nitrogen. Considering the large volume of the test tank 500, the second gas supply pipeline 208 with the gas booster pump 203 is selected in parallel to increase the flow of the gas supply. The nitrogen pressure is increased to the required level by the gas booster pump 203 to ensure the accuracy and safety of the air tightness test. Both gas supply pipelines are equipped with high-precision pressure gauges 204 to monitor pressure changes in real time and prevent overpressure risks. All connection parts use high-strength sealing elements to ensure that there is no gas leakage.

[0024] Further, the gas booster pump 203 on the second gas supply pipeline 208 is provided with a safety valve 211 between the pressure gauge 204, which immediately starts pressure relief once the pressure exceeds the set threshold, ensuring system safety.

[0025] Further, as shown in Figure 3 The driving device 300 includes an air compressor 301, an air tank 302, a second gas triple 303, and a solenoid valve 304. The gas booster pump 203 is driven by compressed air from the air compressor 301. The air compressor 301, the air tank 302, the second gas triple 303, and the solenoid valve 304 are connected in sequence between the air compressor 301 and the gas booster pump 203. The air compressor 301 provides compressed air with a certain pressure for the system. The output pressure and flow rate are determined according to the selected pneumatic valve of the system. The air tank 302 reduces the pressure pulsation of compressed gas and can also store gas to balance the air process and reduce the frequent start and stop of the air compressor 301. The compressed air output by the air compressor 301 may contain impurities such as oil, moisture, and dust, so a filtering device is needed. The filtering device consists of an oil-water separator and an air filter. The precision of the filtering device should be determined according to the requirements of the pneumatic valve.

[0026] Further, as shown in Figure 4 When the tank 500 is subjected to a hydraulic test, pressure preservation needs to be released at the end of the test. The pressure relief system 400 includes a first pressure relief valve 401, a second pressure relief valve 402, a manual pressure relief valve 403, a safety overflow valve 404, and a lower limit pressure regulating device 405. One end of the first pressure relief valve 401, the second pressure relief valve 402, the manual pressure relief valve 403, and the safety overflow valve 404 is connected to the second water supply pipeline 109, and the other end is connected to the water source 101. To achieve automatic control of the pressure relief process, two pneumatic pressure relief valves need to be arranged on the pipeline, one of which can be used as a backup. In addition, a manual pressure relief valve 403 is provided, which can be operated manually in emergency situations to quickly reduce system pressure and ensure test safety.

[0027] Considering that when the pressure cycle experiment is carried out, if the pressure reduction rate is fast and the lower limit of the pressure is set low, a transient vacuum will appear in the gas cylinder, which will affect the accuracy of the test and will also have an adverse effect on the gas cylinder. Therefore, the lower limit of the pressure is usually not set to 0 MPa during the cycle. Usually, the lower limit of the pressure is controlled at about 2 MPa, so a lower limit pressure control device 405 is needed. The lower limit pressure control device 405 includes a lower limit pressure sensor, a PLC controller and a digital display. The lower limit pressure sensor is in communication with the second water supply pipeline 109. The lower limit pressure sensor, the digital display and the PLC controller 701 are electrically connected. The lower limit pressure sensor transmits the pressure of the second water supply pipeline 109 to the PLC controller 701 and displays it on the digital display. The preset value of the PLC controller 701 is set to 2 MPa. When the pressure measured by the lower limit pressure sensor is greater than 2 MPa during pressure relief, the first pressure relief valve 401 or the second pressure relief valve 402 will be in an open state. When the pressure measured by the lower limit pressure sensor is less than or equal to 2 MPa, the second pressure relief valve 402 is closed, and the low-pressure pressure maintaining is completed. In addition, the first pressure relief valve 401 or the second pressure relief valve 402 is connected with the driving device 300 to control its opening and closing.

[0028] The safety overflow valve 404 prevents the system from overpressure and ensures safety. Its set pressure is slightly higher than the highest pressure required by the test. Once it exceeds the set value, it will automatically open the pressure relief.

[0029] Further, the data acquisition and video monitoring system 600 includes a stress and strain monitoring unit, a temperature monitoring unit, a pressure monitoring unit and a high frame rate camera 601. The temperature monitoring unit and the pressure monitoring unit are high-temperature-resistant temperature sensors and pressure sensors, respectively.

[0030] As shown in Figure 5 The stress and strain monitoring unit is an optical fiber grating sensor embedded in the outer wall of the storage tank 500. The stress and strain monitoring unit uses an optical fiber grating strain monitoring system based on the Bragg optical fiber grating sensing technology FBG. The optical fiber grating sensor is embedded in the storage tank 500. The specific process is as follows: Preparation stage: Prepare high-density polyethylene inner cylinder, reinforcing fiber, resin and optical fiber and other materials.

[0031] Winding trial: Lay the optical fiber on the outer wall of the storage tank 500, and then perform reinforcing fiber layer winding process to embed the optical fiber between the inner cylinder outer wall and the reinforcing fiber layer.

[0032] When the water pressure blasting test is carried out, the failure mode needs to be explored, and the test personnel needs to observe the state of the tank in real time when remotely operating, therefore, a high-frame-rate camera 601 with waterproof and explosion-proof functions needs to be arranged in the test area of the tank 500. Video data is transmitted to the control system through an optical fiber, so as to facilitate the test personnel to analyze in real time. At the same time, the system is equipped with a data storage device to ensure that all test data is saved completely.

[0033] Further, as shown in Figure 6 , the control system 700 includes a PLC controller 701, an A / D signal conversion module 702 and a D / A signal conversion module 703. The stress and strain monitoring unit, the temperature monitoring unit and the pressure monitoring unit convert the collected analog signals into digital signals through the A / D signal conversion module 702 and transmit them to the PLC controller 701. The PLC controller 701 converts the received digital signals into analog signals through the D / A signal conversion module 703, which is used to control the actuator. The software system communicates with the computer through digital signals and computer, controls the booster system, water supply system, pressure relief system and driving device according to the test data collected by the pressure sensor and temperature sensor and the experimental parameters preset by the computer, so as to realize the automatic control of pressure boosting, pressure maintaining and pressure relief. At the same time, the data collected by the sensor is converted into digital signals and transmitted to the computer for processing and saving. At the same time, the matching control software can input test parameters and record and process test data in real time, realizing the connection between the computer and the controller. The core logic of the control system 700 is to realize the precise control of pressure through PLC programming, ensuring the stability and controllability of pressure during the test. At the same time, the multifunctional data acquisition card collects sensor data in real time and transmits them to the computer for storage and analysis, ensuring the integrity and accuracy of the data. The linkage mechanism of the safety valve 211 and the pressure relief system 400 further ensures the safety of the test. The actuator includes low-pressure pump 102, booster pump 104, gas booster pump 203 and various valves such as electromagnetic valve 304, first pressure relief valve 401 and second pressure relief valve 402.

[0034] As shown in Figure 7 , it is the logic of automatic control of the valve. The sensor feeds back the signal to the PLC controller, which transmits the electrical signal to the electromagnetic valve. After receiving the electrical signal, the electromagnetic valve switches the path and drives the cylinder to move, realizing the opening or closing of the valve, ensuring the accuracy and timeliness of pressure control. Through this closed-loop feedback mechanism, the whole hardware control system effectively improves the stability and safety of the test.

[0035] Test steps:

[0036] Start-up preparation (1) Confirm the safety environment. Check whether the safety isolation measures are intact, clear the site of irrelevant personnel, and check whether the emergency shutdown button is reset.

[0037] (2) Equipment inspection. Check the normality of sensing equipment such as temperature sensor, pressure sensor, pneumatic regulating valve and other elements, calibrate the pressure gauge, and check whether the opening and closing states of the manual valve in the system are correct. The initial state of the manual pressure relief valve should be closed, and the valve on the water supply pipeline should be open.

[0038] (3) Power supply and gas source inspection. Confirm that the power supply connection is stable, the gas source pressure meets the requirements, and the gas supply system is leak-free.

[0039] (4) Pneumatic valve initialization. Power on the pressure retaining valve 105, the first pressure relief valve 401 and the second pressure relief valve 402, open the pressure retaining valve 105, and close the first pressure relief valve 401 and the second pressure relief valve 402. The response time of the first pressure relief valve 401 and the second pressure relief valve 402 needs to be tested and confirmed to ensure that they can be started quickly when the pressure is too high. Check whether the gas source pressure is stable to ensure that the gas supply system is leak-free. After all the checks are correct, record the initial parameters and prepare for the test phase.

[0040] (5) System pre-filling and degassing. Open the low-pressure pump 102, fill water into the test tank 500 and the water tank 103, and record the initial water level of the water tank 103. Open the exhaust valve, use the high-pressure circulation method to repeatedly pressurize and depressurize, use pressure fluctuation to disturb the air pocket, and make the air gather to the high-level exhaust port until the gas is exhausted. During this period, check whether there is water leakage in the pipeline, valve and tank. If water leakage is found, stop filling immediately and repair the leakage. After ensuring that there is no leakage and the degassing is completed, close the exhaust valve and prepare for the test. After the low-pressure first water supply channel 108 fills the tank 500 with water, the tank 500 switches to the second water supply channel 109 where the booster pump 104 is located, and the first water supply channel 108 and the second water supply channel 109 are connected by a high-pressure hose.

[0041] (6) Preparation before starting the booster pump 104: check whether all parts and accessories are complete and intact; check and ensure that the plunger connecting screw, locking plate and other parts are tightened; check whether the lubricating oil in the transmission case and crankcase is deteriorated, and confirm that the lubricating oil level is above half of the scale; confirm that the water supply pipe has been connected and tightened.

[0042] Hydrostatic test As shown in Figure 8 , the main purpose of the pressure test is to check the pressure-bearing strength and structural integrity of the pressure vessel. According to the national standard, newly designed tanks need to be tested one by one before leaving the factory. The hydrostatic test is not a destructive test, so the hydrostatic test is the first process of the entire test.

[0043] 1. Open the control software of the host computer, select "hydrostatic test mode" in the project, fill in the test pressure, pressure holding time and allowable pressure drop. After confirming the parameters, click the "start" button. The system automatically executes according to the preset program.

[0044] 2. The booster pump 104 starts, the pressure sensor reading is observed, and after slowly increasing the pressure to the specified test pressure, the booster pump 104 is turned off, and the pressure holding stage is entered. The pressure holding valve 105 connected to the storage tank 500 is closed, and the first pressure relief valve 401 on the pump side is opened to release the pressure on the pump side. If the test storage tank 500 under test has a pressure drop exceeding the set "allowable pressure drop" at the test pressure, the pressure relief program will be triggered.

[0045] 3. The pressure holding time ends, the second pressure relief valve 402 is automatically opened to slowly release the pressure to normal pressure, the test data is recorded, and the appearance of the container and the connection part are checked to ensure that there is no leakage, deformation or other abnormal phenomena. After the test is qualified, the accumulated water in the container is emptied, nitrogen is blown to dry, and the subsequent process is prepared. If abnormalities are found, detailed records and analysis of the causes are required, and repair or retesting is necessary.

[0046] During the pressure holding period, the actual test pressure should not be lower than the specified test pressure, and at the end of the pressure holding time, the actual test pressure and the volume deformation should remain stable. Observe the deformation, leakage and other conditions of the gas cylinder, and record the amount of water injected.

[0047] Pressure cycle test As shown in Figure 9 , the pressure cycle test is also called hydraulic pulse test. Its working principle is based on hydraulic transmission and control technology. By repeatedly applying hydraulic pulses, the fatigue life of the test container can be evaluated by simulating the pressure fluctuations it undergoes during long-term use. Through fatigue life testing, it can be known in advance whether the container will leak, rupture or other failure phenomena after a certain number of pressure cycles.

[0048] The hydraulic fatigue test of the storage tank 500 raises the pressure of the water to the set value by the booster pump 104, and cooperates with the pneumatic stop valve and pressure relief valve to realize the pressure cycle process of pressure increase-pressure holding-pressure relief-pressure holding. The data acquisition system can collect and store the pressure and temperature data during the test process.

[0049] Under normal temperature conditions, the pressure cycle test is carried out according to GB / T 9252-2017 "Gas Cylinder Pressure Cycle Test Method". The upper limit of the cycle pressure is 1.25 times the design pressure, the lower limit of the pressure cycle is not more than 10% of the design pressure, and not more than 3 MPa, the cycle frequency is not more than 5 times / min, and the temperature on the surface of the tank body during the test process is not more than 50 °C.

[0050] The implementation of the pressure cycle process is a key issue in the design of the test device. Due to the large volume of the storage tank 500 to be tested, the large flow rate of the pipeline output, and the high output pressure, it is determined that the motor driving the plunger pump has a large power, and the conversion of pressure boosting and pressure maintaining cannot be realized by controlling the start and stop of the plunger pump, otherwise frequent start and stop will seriously affect the service life of the motor. Therefore, the pressure cycle process needs to be realized through the cooperation of the pipeline valve system, and the specific operation steps are as follows: (1) Test preparation stage: open the control software, select "pressure cycle test mode", input initial parameters: cycle number, pressure upper limit, pressure upper limit pressure maintaining time, pressure lower limit, pressure lower limit pressure maintaining time and allowable pressure drop. After determining the above parameters, click the "start" button, and the test will automatically start according to the preset program.

[0051] (2) Pressure boosting stage: open the pressure maintaining valve between the booster pump and the tested container, and water enters the tested container. When the pressure reaches the set pressure upper limit, the connecting pipeline between the booster pump and the tested container should be closed, and the upper limit pressure maintaining stage is entered; (3) Pressure upper limit pressure maintaining stage: when the pressure maintaining time reaches the preset target, the pressure maintaining valve 105 is closed, and the first pressure relief valve 401 at the end of the tested storage tank is opened, so that the medium output by the booster pump 104 is discharged and flows back to the water source or water tank, releasing the pressure on the pump side. Until the preset pressure maintaining time is reached; (4) Pressure relief stage: when the pressure maintaining time reaches the specified requirement, the second pressure relief valve 402 of the backflow pipeline is opened, and the medium in the tested storage tank 500 will be discharged to the water source through the pipeline where the second pressure relief valve 402 is located, so that the pressure gradually decreases to the preset pressure lower limit.

[0052] (5) Pressure lower limit pressure maintaining stage: when the pressure reaches the preset pressure lower limit, the second pressure relief valve 402 is automatically closed, and the pressure lower limit pressure maintaining stage is entered. After the pressure maintaining time is completed, the pressure maintaining valve between the booster pump and the tested gas cylinder is opened, and the next pressure cycle is entered.

[0053] (6) Repeat the above process to realize multiple pressure cycles.

[0054] Contents to be monitored and recorded: 1) Tank surface temperature during the test; 2) Cycle number; 3) Cycle pressure upper limit and lower limit value; 4) Cycle frequency; 5) Pressure-time curve; If the tested container fails due to fatigue within the specified number of cycles, record the specific conditions of the failure form, including the failure position, form and cycle number.

[0055] Water pressure blasting test IfFigure 10 The purpose of the water pressure test is to check the mechanical properties, the rationality and reliability of the structural design, the size of the actual safety margin, and other aspects. The water pressure test procedure is carried out in accordance with GB / T 15385-2022 “Gas Cylinder Water Pressure Test Method”. The specific steps are as follows: Open the control software and select the “water pressure test mode”. Input the parameters: initial target pressure, initial pressure holding time, step pressure increase, pressure increase rate, pressure holding time at each level, and allowable pressure drop. After confirming the parameters, open the “start” button, and the system will automatically follow the preset program.

[0056] 1. Pressure increase stage The logic of the pressure increase stage is the same as the water pressure test. Turn on the booster pump 104 and the pressure holding valve 105, limit the speed within 1 MPa / s to pressurize the system to the design pressure of the test container. When the design pressure is reached, close the pressure holding valve and open the first pressure relief valve 401 to bypass the water on the pump side back to the water tank 103.

[0057] 2. Pressure holding stage During the pressure holding stage of the test container, turn off the booster pump 104 and the pressure holding valve 105. Observe the pressure drop of the system during the pressure holding period to monitor the leakage of the test container. If the pressure drop is less than 0.01 MPa / s, it is considered that the entire system is well sealed and the next step can be continued.

[0058] 3. Step pressure increase stage After the pressure holding is completed, use a segmented pressure increase strategy, with a pressure increase rate not exceeding 0.5 MPa / s. Each pressure increase level requires a pressure holding time of not less than 30s. Continue the step pressure increase until the test cylinder explodes.

[0059] 4. Instantaneous response of explosion The risk is highest at the moment of explosion, and the safety device must respond within milliseconds. At the moment of explosion, the pressure drops suddenly, the container surface vibrates violently and produces a loud noise. When the pressure drop exceeds the pre-set allowable pressure drop before the test, the booster pump stops immediately, and the first pressure relief valve 401 and the second pressure relief valve 402 automatically open fully. At the same time, vibration sensors are placed on the outer surface of the test container and are interlocked with the automatic control system. When the vibration frequency abnormally increases, it will also trigger the emergency stop device.

[0060] During the test, the following contents need to be monitored and automatically recorded: (1) Total water inflow from the start of pressurization to the moment of cylinder explosion; (2) Automatically draw and save the pressure-time curve; (3) Automatically record the explosion pressure; (4) High-frame-rate camera 601 records the failure mode description, including the location of the rupture, the length of the rupture, and the maximum width of the rupture.

[0061] Emergency plan and matters needing attention of water pressure blasting test: 1) In the process of pressure increasing, if the pressure increasing speed is obviously accelerated or slowed down, the test should be stopped immediately, the booster pump 104 should be closed, the cause should be found out and eliminated.

[0062] 2) Any maintenance or adjustment operation is strictly prohibited under pressure, and no one should approach the test tank 500 during pressure increasing.

[0063] Air tightness test As shown in the successful water pressure test, pressure cycle test and water pressure blasting test, the air tightness test can be carried out. The specific steps of air tightness test are as follows: Figure 11 (1) Fix the test tank 500 in the safety pool, check whether the pipeline connection is perfect. (2) Before the air tightness test of each test tank 500, the pre-test is water pressure test. After verifying the integrity of the tank structure, the air tightness test can be carried out. If a new test tank is replaced without water pressure test, the water pressure test should be carried out according to the steps, and then the subsequent steps can be continued. If the test tank 500 has been tested by water pressure test before, this step can be skipped.

[0064] (3) Open the tank exhaust valve, open the valve on the gas supply main pipe, close the valve on the branch of the booster pump 104, open the branch valve connected to the test tank 500, and then open the first needle valve 209 of the gas source to supply nitrogen to the test tank 500. Nitrogen is blown and dried in the test tank 500, and the residual moisture on the tank wall is dried.

[0065] (4) After nitrogen blowing is completed, close the first needle valve 209 of the nitrogen source to suspend gas supply, close the exhaust valve of the test tank, and then gradually open the first needle valve 209 of the gas source to pre-pressurize the test tank 500 by using the pressure difference of the gas source 201, until the pressure gauge is stable and no longer rises, indicating that the pressure of the test tank 500 is equal to the pressure of the gas source 201.

[0066] (5) Close the valve of the branch connected to the test tank 500, open the second needle valve 210 of the branch of the gas booster pump 203, start the gas booster pump 203, and pressurize the test tank 500. When the pressure is increased to 10% of the target pressure, the pressure is maintained for 5-10 min, and the leakage of all welded joints and connection parts is checked. If there is leakage, the pressure should be released first, then the test should be retested after repair welding. If there is no abnormal phenomenon, the pressure can be slowly increased to 50% of the specified pressure, and then the target pressure can be increased.

[0067] ​

[0068] (6) After the pressure is increased to the target pressure, the qualified standard is that the test tank 500 has no abnormal sound, the safety pool has no obvious bubbles, and the pressure should remain unchanged during the pressure maintaining period.

[0069] During the pressure increasing process of the gas booster pump 203, the test personnel are strictly prohibited from approaching the test tank area. The test personnel observe the state of the tank and the safety pool through the video monitoring system. If abnormal conditions (such as a large number of bubbles on the surface of the pool, a significant pressure drop, etc.) are found, the pump is stopped in time and the pressure is released for inspection.

[0070] During the experiment, the pressure, temperature and other parameters are collected and recorded throughout the process.

[0071] Normal shutdown procedure Under the premise that the above test is completed and no emergency shutdown is triggered, the normal shutdown process is performed. Click the "stop" button on the control software, and the PLC sends a stop command to the booster pump. The booster pump motor speed gradually decreases to 0. At the same time, the pressure maintaining valve and the pressure relief valve are powered off and reset. The pressure gauge is observed until the pressure drops to 0. The air compressor is turned off. The test data is backed up, and a comprehensive safety check of the test site is performed.

[0072] Emergency shutdown procedure (1) Triggering conditions of emergency stop: (2) When the pressure drop is greater than the allowed pressure drop set by the user; (3) When the vibration sensor detects an abnormal increase in vibration acceleration, which exceeds the allowed vibration acceleration set by the user, the emergency stop button will be triggered.

[0073] If the on-site operator finds that the test is abnormal and the program does not respond, press the emergency shutdown switch or click "stop" on the control software. The emergency stop program will also be triggered.

[0074] When the emergency stop program is triggered, the emergency stop signal is transmitted directly to the booster pump and the valve through the safety relay. The booster pump motor is powered off in an emergency, the electromagnetic coil power supply of the control pressure maintaining valve and the pressure relief valve is cut off, the pressure maintaining valve is closed, the pressure relief valve is opened, and the pressure is quickly released. At the same time, the cabinet warning red light is on, and the sound and light alarm system is pneumatic. The on-site personnel evacuate in an emergency, and can go to the test site for investigation after confirming safety.

[0075] The above is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent transformation or direct or indirect application of the contents of the specification and drawings in related technical fields is also included in the patent protection scope of the present application.

Claims

1. A high-pressure hydrogen storage pressure vessel comprehensive test device, characterized in that: The application relates to a water supply system (100), a gas supply system (200), a driving device (300), a pressure relief system (400), a storage tank (500), a data acquisition and video monitoring system (600) and a control system (700), wherein one end of the storage tank (500) is provided with a storage tank air inlet (501), the water supply system (100) and the gas supply system (200) are communicated with the storage tank air inlet (501), the pressure relief system (400) is connected with the water supply system (100) and is used for relieving the pressure of liquid in the storage tank (500), the driving device (300) is connected with the gas supply system (200) and is used for driving a gas booster pump (203) in the gas supply system (200), the data acquisition and video monitoring system (600) is used for monitoring the data of the storage tank (500), and the data acquisition and video monitoring system (600) is electrically connected with the control system (700).

2. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 1, characterized in that: The water supply system (100) comprises a water source (101), a low-pressure pump (102), a water tank (103), a booster pump (104) and a pressure maintaining valve (105), the input end of the low-pressure pump (102) is connected with the water source (101), the output end of the low-pressure pump (102) is connected with the input end of a water supply three-way pipe (113), the first output end of the water supply three-way pipe (113) is communicated with the storage tank air inlet (501) of the storage tank (500) through a first water supply pipeline (108), a first water supply stop valve (110) is arranged on the first water supply pipeline (108), the second output end of the water supply three-way pipe is communicated with the storage tank air inlet (501) through a second water supply pipeline (109), and the second water supply pipeline (109) is sequentially connected with a second water supply stop valve (111), the water tank (103), a third water supply stop valve (112), the booster pump (104) and the pressure maintaining valve (105).

3. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 2, characterized in that: A filter (106) is arranged between the low-pressure pump (102) and the water source (101), between the second water supply stop valve (111) and the second output end of the water supply three-way pipe (113) and between the third water supply stop valve (112) and the water tank (103), a liquid level sensor is arranged in the water tank (103), and a check valve (107) is arranged between the booster pump (104) and the pressure maintaining valve (105).

4. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 2, characterized in that: The booster pump (104) is a high-pressure three-plunger pump.

5. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 1, characterized in that: The gas supply system (200) comprises a gas source (201), a first gas tee joint (202), a gas booster pump (203) and a pressure gauge (204), the input end of the first gas tee joint (202) is connected with the gas source (201) through a gas supply stop valve (205), the output end of the first gas tee joint (202) is connected with the input end of a gas supply tee (206), the first output end of the gas supply tee (206) is connected with the tank inlet liquid port (501) through a first gas supply pipeline (207), the first gas supply pipeline (207) is provided with a first needle valve (209) and a pressure gauge (204); the second output end of the gas supply tee (206) is connected with the tank inlet liquid port (501) through a second gas supply pipeline (208), the second gas supply pipeline (208) is sequentially provided with a second needle valve (210), a gas booster pump (203) and a pressure gauge (204).

6. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 5, characterized in that: The gas booster pump (203) and the pressure gauge (204) on the second gas supply pipeline (208) are provided with a safety valve (211) therebetween.

7. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 6, characterized in that: The driving device (300) comprises an air compressor (301), a gas storage tank (302), a second gas tee joint (303) and a solenoid valve (304), the gas booster pump (203) is driven by compressed air of the air compressor (301), the air compressor (301) and the gas booster pump (203) are sequentially connected with the gas storage tank (302), the second gas tee joint (303) and the solenoid valve (304).

8. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 1, characterized in that: The pressure relief system (400) comprises a first pressure relief valve (401), a second pressure relief valve (402), a manual pressure relief valve (403), a safety overflow valve (404) and a lower limit pressure adjusting device (405), one end of the first pressure relief valve (401), the second pressure relief valve (402), the manual pressure relief valve (403) and the safety overflow valve (404) is communicated with the second water supply pipeline (109), the other end is connected with the water source (101); the lower limit pressure adjusting device (405) comprises a lower limit pressure sensor, a PLC controller and a digital display meter, the lower limit pressure sensor is communicated with the second water supply pipeline (109), the lower limit pressure sensor, the digital display meter and the PLC controller are electrically connected.

9. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 8, characterized in that: The data acquisition and video monitoring system (600) comprises a stress and strain monitoring unit, a temperature monitoring unit, a pressure monitoring unit and a high frame rate camera (601), the temperature monitoring unit and the pressure monitoring unit are respectively communicated with the inner cavity of the tank (500); the stress and strain monitoring unit is an optical fiber grating sensor embedded on the outer wall of the tank (500); the high frame rate camera (601) is arranged above the tank (500) for observing the state of the tank (500).

10. The high-pressure hydrogen storage pressure vessel comprehensive test device according to claim 9, characterized in that: The control system (700) comprises a PLC controller (701), an A / D signal conversion module (702) and a D / A signal conversion module (703), the stress-strain monitoring unit, the temperature monitoring unit and the pressure monitoring unit transmit the collected analog signals to the PLC controller (701) by the A / D signal conversion module (702) to be converted into digital signals, and the PLC controller (701) converts the received digital signals into analog signals by the D / A signal conversion module (703) to control the actuator.

Images