Liquid hydrogen valve testing device

Abstract

The utility model discloses a liquid hydrogen valve testing device which comprises a vacuum cold box, a high-pressure nitrogen cylinder, a high-pressure hydrogen cylinder, a liquid helium storage tank and a liquid nitrogen storage tank. Outlets of the liquid helium storage tank, the liquid nitrogen storage tank, the high-pressure nitrogen cylinder and the high-pressure hydrogen cylinder pass through respective valves and then are combined and connected to an inlet main pipeline; the inlet main pipeline is divided into an inlet branch and an inlet vaporization pipeline; the inlet branch enters the vacuum cold box and is connected with a to-be-tested valve; the outlet of the to-be-tested valve is connected with an outlet main pipeline, and the outlet main pipeline is divided into a first outlet branch and a second outlet branch; the first outlet branch is sequentially connected with an outlet vaporization valve, a second water bath vaporizer and a detection main valve and then is divided into a first detection branch and a second detection branch; and the second detection branch is connected with an alcohol bubble meter, a gas collection detector and a flow meter through a first detection valve, a second detection valve and a flow detection valve respectively. According to the utility model, a 20K-300K low-temperature environment and a high-pressure hydrogen environment can be provided for the valve to be tested, so that the reliability of the valve can be accurately verified.

Description

Technical Field

[0001] The utility model belongs to the field of valve testing, in particular to a liquid hydrogen valve testing device. Background Technique

[0002] Liquid hydrogen has great application prospects in the fields of energy storage, fuel, chemical industry, reducing agent, etc. Since hydrogen is inflammable and explosive, and it is very uneconomical to store or transport it in gaseous form, hydrogen is usually converted into liquid hydrogen. Liquid hydrogen is stored or used under high pressure and extremely low temperature, so the reliability of liquid hydrogen valves in the system becomes crucial.

[0003] In order to avoid safety accidents caused by internal leakage or external leakage of the valve itself during the use of the liquid hydrogen valve after installation, it is very necessary to test the hydrogen valve under low temperature and high pressure before installing the hydrogen valve to verify the reliability of the valve. After passing the test, the hydrogen valve can effectively avoid safety accidents caused by valve reliability problems when assembled into the system, reducing economic losses.

[0004] Chinese patent document with publication number CN117824953A discloses a multi-state liquid hydrogen valve testing device and its testing method, including a helium pressurization pipeline, a high-pressure helium gas cylinder, a helium gas switching valve, a first helium gas pressure reducing valve, a first helium gas stop valve, a first pressure sensor; by regulating the temperature and pressure parameters of the liquid hydrogen medium flowing through the test valve before and after, in addition to the conventional saturated state, tests under various complex working conditions such as supercritical hydrogen, subcooled hydrogen, and transcritical hydrogen can also be realized; by adjusting the liquid hydrogen flow rate flowing through the test valve before and after, tests under two working conditions of stable flow and fluctuating flow can be realized; at the same time, through devices such as a helium mass spectrometer and a flowmeter provided, test contents such as internal leakage and external leakage of the valve can be effectively realized.

[0005] However, in the above-mentioned existing patent, the gas in the valve is directly discharged from the flowmeter after the test. If the volume of the valve and the test pipeline is large, directly discharging a large amount of low-temperature gas is likely to damage the flowmeter; in addition, a safety relief device is not provided on the test pipeline in the above-mentioned existing patent, and the test working medium contains hydrogen, increasing the danger during the use of the equipment. Content of the Utility Model

[0006] The utility model provides a liquid hydrogen valve testing device, which can provide a low-temperature environment of 20K - 300K and a high-pressure hydrogen environment for the valve to be tested, so as to accurately verify the reliability of the valve, improve the safety of the test process at the same time, and prevent the leakage of test gas.

[0007] A liquid hydrogen valve testing device includes a vacuum cold box, a high-pressure nitrogen gas cylinder, a high-pressure hydrogen gas cylinder, a liquid helium storage tank, and a liquid nitrogen storage tank;

[0008] The outlets of the liquid helium storage tank and the liquid nitrogen storage tank are respectively merged and connected to the inlet main pipeline after passing through the liquid helium inlet valve and the liquid nitrogen inlet valve;

[0009] The outlet of the high-pressure nitrogen gas cylinder is sequentially connected to a nitrogen pressure reducing valve, a nitrogen inlet valve, and an intake main valve and then connected to the inlet main pipeline; the outlet of the high-pressure hydrogen gas cylinder is sequentially connected to a hydrogen pressure reducing valve, a hydrogen inlet valve, and an intake main valve and then connected to the inlet main pipeline;

[0010] The inlet main pipeline is divided into an inlet branch and an inlet vaporization pipeline; the inlet branch enters the interior of the vacuum cold box and is connected to the inlet of the valve to be tested; the outlet of the valve to be tested is connected to the outlet main pipeline, and the outlet main pipeline extends outside the vacuum cold box and is divided into a first outlet branch and a second outlet branch;

[0011] The first outlet branch is sequentially connected to an outlet vaporization valve, a second water bath vaporizer, and a detection main valve and then divided into a first detection branch and a second detection branch; the first detection branch is respectively connected to an alcohol meter bubbler, a gas collection detector, and a flow meter through a first detection valve, a second detection valve, and a flow detection valve);

[0012] The second outlet branch and the inlet vaporization pipeline are merged and then sequentially connected to a first water bath vaporizer and a first evacuation main valve, and after being merged with the second detection branch, they are connected to a pressure relief pipeline through a second evacuation main valve.

[0013] Furthermore, an inlet pressure sensor is installed on the inlet main pipeline.

[0014] Furthermore, a first safety valve is provided between the nitrogen pressure reducing valve and the nitrogen inlet valve, and a fourth safety valve is connected to the pressure relief pipeline between the hydrogen pressure reducing valve and the hydrogen inlet valve.

[0015] Furthermore, an internal leakage detection pipeline and a vacuum pumping pipeline are provided on the vacuum cold box; among them, the internal leakage detection pipeline is connected to a helium mass spectrometer leak detector after passing through an internal leakage detection valve, and the vacuum pumping pipeline is connected to a vacuum unit after passing through a cold box evacuation valve.

[0016] Furthermore, a second safety valve is connected to the pressure relief pipeline between the first water bath vaporizer and the first evacuation main valve.

[0017] Furthermore, a pipeline provided with a third safety valve is connected to the pressure relief pipeline between the second water bath vaporizer and the detection main valve; a reverse intake pipeline is provided between the third safety valve and the detection main valve, and the reverse intake pipeline is connected to a reverse inlet valve; a second pressure sensor is provided on the reverse intake pipeline.

[0018] Furthermore, a recovery main valve is connected through a pipeline on the second detection branch.

[0019] Furthermore, an outlet side bypass valve is provided on the second outlet branch.

[0020] Compared with the prior art, the utility model has the following beneficial effects:

[0021] 1. All low-temperature fluids are reheated by the vaporizer before being discharged or measuring the flow rate, which reduces the requirements for measuring components such as flow meters and improves the stability of the test device.

[0022] 2. Necessary safety valves are provided on the test pipeline to avoid danger caused by excessive internal pressure of the pipeline and improve the safety of the test device.

[0023] 3. All gas discharge ports are gathered together through pipelines, which is convenient for centralized discharge or recovery of the discharged gas during the use of the test device.

[0024] 4. A reverse intake pipeline is provided, so that the test device can be used for testing some valves (such as check valves) that require reverse inflation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of a liquid hydrogen valve test device of the utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following further describes the present utility model in detail with reference to the drawings and embodiments. It should be noted that the following embodiments are intended to facilitate the understanding of the present utility model and do not limit it in any way.

[0027] As Figure 1 shown, a liquid hydrogen valve test device includes a vacuum cold box 1, a valve under test 2, a first temperature sensor 3, a second temperature sensor 4, a high-pressure nitrogen cylinder 5, a high-pressure hydrogen cylinder 6, a hydrogen pressure reducing valve 7, a nitrogen pressure reducing valve 8, a first safety valve 9, a nitrogen inlet valve 10, a hydrogen inlet valve 11, a liquid helium storage tank 12, a liquid nitrogen storage tank 13, a liquid nitrogen inlet valve 14, a liquid helium inlet valve 15, an inlet pressure sensor 16, an outlet side bypass valve 17, an outlet vaporizing valve 18, an internal leakage detection valve 19, a cold box evacuation valve 20, a first water bath vaporizer 21, a second safety valve 22, a second water bath vaporizer 23, a third safety valve 24, a second pressure sensor 25, a reverse inlet valve 26, a detection main valve 27, a first exhaust main valve 28, a recovery main valve 29, a first detection valve 30, an alcohol meter bubbler 31, a second detection valve 32, a gas collection detector 33, a flow detection valve 34, a flow meter 35, a pressure relief pipeline 36, an inlet main pipeline 37, an inlet vaporizing pipeline 38, an outlet main pipeline 39, a reverse intake pipeline 40, a first detection branch 41, a fourth safety valve 42, a diffuser 43, an intake main valve 44, a second exhaust main valve 45.

[0028] The valve 2 to be tested is installed inside the vacuum cold box 1. A first temperature sensor 3 and a second temperature sensor 4 are installed on the valve 2 to be tested. The first temperature sensor 3 and the second temperature sensor 4 are used to measure the temperature of the valve 2 to be tested.

[0029] The inside of the vacuum cold box 1 is in a vacuum state and is connected to the inlet of the internal leakage detection valve 19 through a pipeline. The outlet of the internal leakage detection valve 19 is connected to a helium mass spectrometer leak detector, which is used to detect the leakage inside the vacuum cold box 1.

[0030] The inside of the vacuum cold box 1 is connected to the inlet of the cold box evacuation valve 20 through a pipeline. The outlet of the cold box evacuation valve 20 is connected to a vacuum unit, which is used to create and maintain the vacuum environment inside the vacuum cold box 1.

[0031] The outlet of the liquid helium storage tank 12 is connected to the inlet of the liquid helium inlet valve 15, and the outlet of the liquid nitrogen storage tank 13 is connected to the inlet of the liquid nitrogen inlet valve 14; the outlets of the liquid helium inlet valve 15 and the liquid nitrogen inlet valve 14 are combined and connected to the inlet main pipeline 37.

[0032] The outlet of the high-pressure nitrogen cylinder 5 is connected to the inlet of the nitrogen pressure reducing valve 8. The outlet of the nitrogen pressure reducing valve 8 is connected to the inlet of the nitrogen inlet valve 10. A first safety valve 9 is installed on the pipeline between the outlet of the nitrogen pressure reducing valve 8 and the inlet of the nitrogen inlet valve 10.

[0033] The outlet of the high-pressure hydrogen cylinder 6 is connected to the inlet of the hydrogen pressure reducing valve 7. The outlet of the hydrogen pressure reducing valve 7 is connected to the inlet of the hydrogen inlet valve 11. A fourth safety valve 42 is installed on the pipeline between the outlet of the hydrogen pressure reducing valve 7 and the inlet of the hydrogen inlet valve 11.

[0034] The outlets of the nitrogen inlet valve 10 and the hydrogen inlet valve 11 are combined and connected to the inlet of the intake main valve 44. The outlet of the intake main valve 44 and the outlets of the liquid helium inlet valve 15 and the liquid nitrogen inlet valve 14 are combined and connected to the inlet main pipeline 37.

[0035] An inlet pressure sensor 16 is installed on the inlet main pipeline 37 and is divided into two paths, namely an inlet branch and an inlet vaporization pipeline 38. The inlet branch enters the inside of the vacuum cold box 1 and is connected to the inlet of the valve 2 to be tested. The outlet of the valve 2 to be tested exits the vacuum cold box 1 and is connected to the outlet main pipeline 39. The outlet main pipeline 39 is divided into two paths, namely a first outlet branch and a second outlet branch. The first outlet branch is connected to the inlet of the outlet vaporization valve 18. The outlet of the outlet vaporization valve 18 is connected to the inlet of the second water bath vaporizer 23. The outlet of the second outlet branch is combined with the inlet vaporization pipeline 38 and connected to the inlet of the first water bath vaporizer 21.

[0036] The outlet of the first water bath vaporizer 21 is connected to the first exhaust main valve 28. The outlet of the first exhaust main valve 28 is divided into two paths, namely a first exhaust branch and a second exhaust branch. The first exhaust branch is connected to the inlet of the second exhaust main valve 45. The outlet of the second exhaust main valve 45 is combined with the pressure relief pipeline 36 and connected to the inlet of the diffuser 43.

[0037] The outlet of the No. 2 water bath vaporizer 23 is divided into two paths, namely the reverse intake pipe 40 and the detection inlet pipe. The outlet of the detection inlet pipe is connected to the detection main valve 27. The outlet of the detection main valve 27 is divided into two paths, namely the first detection branch 41 and the second detection branch. The first detection branch 41 is divided into three paths, which are respectively connected to the inlets of the No. 1 detection valve 30, the No. 2 detection valve 32, and the flow rate detection valve 34. The outlet of the No. 1 detection valve 30 is connected to the alcohol meter bubbler 31, the outlet of the No. 2 detection valve 32 is connected to the gas collection detector 33, and the outlet of the flow rate detection valve 34 is connected to the inlet of the flow meter 35.

[0038] The No. 3 safety valve 24 is installed between the outlet of the No. 2 water bath vaporizer 23 and the reverse intake pipe 40.

[0039] The reverse intake pipe 40 is connected to the reverse inlet valve 26, and a No. 2 pressure sensor 25 is installed between the outlet of the reverse inlet valve 26 and the No. 3 safety valve 24.

[0040] The second detection branch and the second evacuation branch are merged and connected to the inlet of the recovery main valve 29. The outlet of the recovery main valve 29 is connected to a recovery device for recovering helium.

[0041] The outlets of the No. 1 safety valve 9, the No. 2 safety valve 22, and the No. 4 safety valve 42 are merged and connected to the relief pipe 36.

[0042] Using the device of the present utility model to test the liquid hydrogen valve, the operation steps are as follows:

[0043] S100. Purge

[0044] When the equipment is started for the first time or has not been used for a long time, there may be water vapor and dust inside. It is necessary to purge the pipeline.

[0045] First, ensure that all valves are in the closed state. Open the valve to be tested 2, the nitrogen inlet valve 10, the outlet side bypass valve 17, the outlet vaporization valve 18, the detection main valve 27, the No. 1 evacuation main valve 28, and the recovery main valve 29. Connect the outlet of the recovery main valve 29 to the vacuum unit, and first evacuate the inside of the system pipeline. When the pump port pressure < 1×10 -2 Pa, close the vacuum unit and the recovery main valve 29.

[0046] Adjust the outlet pressure of the nitrogen pressure reducing valve 8 to 0.2 MPa, open the No. 2 evacuation main valve 45 to discharge nitrogen, and purge the pipeline. After 1 - 2 minutes, the purging ends. Close the nitrogen pressure reducing valve 8. Close the No. 1 evacuation main valve 28.

[0047] S200. Pre - cool

[0048] Using the internal cooling method, after the purging operation is completed, close the outlet side bypass valve 17, open the liquid nitrogen inlet valve 14 to inject liquid nitrogen into the system. Under the flushing of the liquid nitrogen, the valve under test 2 quickly cools down to 77K. Observe that the temperatures of the first temperature sensor 3 and the second temperature sensor 4 are maintained at the liquid nitrogen temperature for more than 5 minutes. Close the liquid nitrogen inlet valve 14, close the second evacuation main valve 45, open the recovery main valve 29, start the vacuum unit to extract the residual nitrogen. After 5 - 10 minutes, close the vacuum unit and close the recovery main valve 29. Replace the vacuum unit with a helium recovery device or directly evacuate. If directly evacuating, the recovery main valve 29 does not need to be closed. Open the recovery main valve 29 again, open the liquid helium inlet valve 15 to inject liquid helium into the system. Under the flushing of the liquid helium, the valve under test 2 quickly cools down to <20K. Observe that the temperatures of the first temperature sensor 3 and the second temperature sensor 4 are <20K for more than 5 minutes. First, open the first evacuation main valve 28 and close the liquid helium inlet valve 15. Connect the recovery main valve 29 to the vacuum equipment to extract the residual helium. After the pump port vacuum degree <1×10 -2 Pa, close the recovery main valve 29 and the first evacuation main valve 28.

[0049] S300, Test

[0050] 1. Measurement of internal leakage of cryogenic valves.

[0051] After the pre-cooling is completed, close the valve under test 2 according to the specified torque, open the hydrogen pressure reducing valve 7 on the high-pressure hydrogen cylinder 6, and adjust the outlet of the hydrogen pressure reducing valve 7 to the required test pressure. Open the detection main valve 27. Open the first detection valve 30 as required for testing and measure through the alcohol meter bubbler 31. Open the second detection valve 32 and measure through the gas collection detector 33; open the flow detection valve 34 and measure through the flow meter 35.

[0052] 2. Measurement of internal leakage of normal temperature valves

[0053] After the purging is completed, close the valve under test 2 according to the specified torque, open the hydrogen pressure reducing valve 7 on the high-pressure hydrogen cylinder 6, and adjust the outlet of the hydrogen pressure reducing valve 7 to the required test pressure. Open the detection main valve 27. Open the first detection valve 30 as required for testing and measure through the alcohol meter bubbler 31. Open the second detection valve 32 and measure through the gas collection detector 33; open the flow detection valve 34 and measure through the flow meter 35.

[0054] 3. Measurement of external leakage of cryogenic valves

[0055] After the pre-cooling is completed, keep the valve under test 2 in the open state, and keep the outlet side bypass valve 17 and the outlet vaporization valve 18 closed. Open the hydrogen pressure reducing valve 7 on the high-pressure hydrogen cylinder 6, and adjust the outlet of the hydrogen pressure reducing valve 7 to the required test pressure. Connect the internal leakage detection valve 19 to the helium mass spectrometer leak detector to detect the stuffing box, valve body, and valve cover of the valve under test 2.

[0056] 4. Measurement of External Leakage of Valves at Normal Temperature

[0057] After the purging is completed, keep the valve 2 to be tested open, and keep the bypass valve 17 at the outlet side and the vaporization valve 18 at the outlet closed. Open the hydrogen pressure reducing valve 7 on the high-pressure hydrogen cylinder 6, and adjust the outlet of the hydrogen pressure reducing valve 7 to the required test pressure. Connect the internal leakage detection valve 19 to a helium mass spectrometer leak detector to detect leaks at the stuffing box, valve body, and valve cover of the valve 2 to be tested.

[0058] 5. Sealing Performance Test of Non-Metallic Materials

[0059] After the purging is completed, close the bypass valve 17 at the outlet side, the vaporization valve 18 at the outlet, and the No. 1 total vent valve 28. Open the valve 2 to be tested, open the hydrogen pressure reducing valve 7 on the high-pressure hydrogen cylinder 6, and adjust the outlet of the hydrogen pressure reducing valve 7 to the maximum pressure allowed for the valve 2 to be tested at 20 °C, and keep it for 70 h. Connect the internal leakage detection valve 19 to a helium mass spectrometer leak detector to detect leaks at the stuffing box, valve body, and valve cover of the valve 2 to be tested.

[0060] 6. Emission Test at Normal Temperature

[0061] After the purging is completed, keep the valve 2 to be tested open, and keep the bypass valve 17 at the outlet side and the vaporization valve 18 at the outlet closed. Open the hydrogen pressure reducing valve 7 on the high-pressure hydrogen cylinder 6, and adjust the outlet of the hydrogen pressure reducing valve 7 to the required test pressure. Connect the internal leakage detection valve 19 to a helium mass spectrometer leak detector to detect leaks at the stuffing box, valve body, and valve cover of the valve 2 to be tested. Close the valve 2 to be tested, then fully open and fully close the valve 2 to be tested five times. After completing the mechanical cycle, open the valve under test to the half-open state, and detect leaks at the stuffing box, valve body, and valve cover of the valve 2 to be tested.

[0062] The above-described embodiments have detailed the technical solutions and beneficial effects of the present utility model. It should be understood that the above are only specific embodiments of the present utility model and are not used to limit the present utility model. Any modifications, supplements, and equivalent replacements made within the scope of the principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A liquid hydrogen valve testing device, characterized in that: It comprises a vacuum cold box (1), a high-pressure nitrogen cylinder (5), a high-pressure hydrogen cylinder (6), a liquid helium storage tank (12), and a liquid nitrogen storage tank (13); The outlets of the liquid helium storage tank (12) and the liquid nitrogen storage tank (13) are respectively connected to the inlet main pipeline (37) after passing through the liquid helium inlet valve (15) and the liquid nitrogen inlet valve (14); The outlet of the high-pressure nitrogen cylinder (5) is connected to the nitrogen pressure reducing valve (8), the nitrogen inlet valve (10), the main air intake valve (44) in sequence, and then connected to the main inlet pipeline (37); the outlet of the high-pressure hydrogen cylinder (6) is connected to the hydrogen pressure reducing valve (7), the hydrogen inlet valve (11), the main air intake valve (44) in sequence, and then connected to the main inlet pipeline (37); The inlet main pipeline (37) is divided into an inlet branch and an inlet vaporization pipeline (38); the inlet branch enters the interior of the vacuum cold box (1) and is connected to the inlet of the valve to be tested (2); the outlet of the valve to be tested (2) is connected to the outlet main pipeline (39), and the outlet main pipeline (39) is extended to the outside of the vacuum cold box (1) and is divided into a first outlet branch and a second outlet branch; The first outlet branch is connected in sequence to the outlet vaporization valve (18), the No. 2 water bath vaporizer (23), and the main detection valve (27), and then is divided into a first detection branch (41) and a second detection branch; the first detection branch (41) is connected to the alcohol bubble counter (31), the gas collection detector (33), and the flow meter (35) through the No. 1 detection valve (30), the No. 2 detection valve (32), and the flow detection valve (34); The second outlet branch and the inlet vaporization pipeline (38) are connected in sequence to the No. 1 water bath vaporizer (21) and the No. 1 exhaust main valve (28) after being combined, and are connected to the pressure relief pipeline (36) through the No. 2 exhaust main valve (45) after being combined with the second detection branch.

2. The liquid hydrogen valve testing device according to claim 1, characterized in that: An inlet pressure sensor (16) is installed on the inlet main pipeline (37).

3. The liquid hydrogen valve testing device according to claim 1, characterized in that: A No. 1 safety valve (9) is provided between the nitrogen pressure reducing valve (8) and the nitrogen inlet valve (10), and a No. 4 safety valve (42) is connected to the pressure relief pipeline (36) between the hydrogen pressure reducing valve (7) and the hydrogen inlet valve (11).

4. The liquid hydrogen valve testing device according to claim 1, characterized in that: The vacuum cold box (1) is provided with an internal leakage detection pipeline and a vacuum pumping pipeline; wherein the internal leakage detection pipeline is connected to the helium mass spectrometer leak detector after passing through the internal leakage detection valve (19), and the vacuum pumping pipeline is connected to the vacuum unit after passing through the cold box evacuation valve (20).

5. The liquid hydrogen valve testing device according to claim 1, characterized in that: The No. 1 water bath vaporizer (21) and the No. 1 exhaust main valve (28) are connected to a pressure relief pipeline (36) via a No. 2 safety valve (22).

6. The liquid hydrogen valve testing device according to claim 1, characterized in that: A pipeline connected to a No. 3 safety valve (24) is provided between the No. 2 water bath vaporizer (23) and the main detection valve (27) to a pressure relief pipeline (36); a reverse air intake pipeline (40) is provided between the No. 3 safety valve (24) and the main detection valve (27), and the reverse air intake pipeline (40) is connected to a reverse inlet valve (26); and a No. 2 pressure sensor (25) is provided on the reverse air intake pipeline (40).

7. The liquid hydrogen valve testing device according to claim 1, characterized in that: The second detection branch is connected to the recovery main valve (29) via a pipeline.

8. The liquid hydrogen valve testing device according to claim 1, characterized in that: An outlet-side bypass valve (17) is provided on the second outlet branch.

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