Hydrogen and nitrogen leak detection system and leak detection method thereof

Abstract

The invention discloses a hydrogen and nitrogen leak detection system which comprises a test cover, a vacuum module and a hydrogen and nitrogen leak detection module. The invention further provides a hydrogen and nitrogen leakage detection method. Compared with the prior art, the hydrogen and nitrogen leak detection system and the leak detection method thereof have the beneficial effects that the test cover is introduced and matched with the vacuum module to artificially construct a vacuum environment, so that the detection requirements in different pressure environments can be flexibly met, the interference of environmental noise on the leak detection result is eliminated, and residual air is prevented from diluting hydrogen and nitrogen; and the detection precision and the detection speed are greatly improved. Besides, by setting a multi-level judgment mechanism, the leakage rate of the detected product can be detected on the premise of ensuring that the detected product does not have a large-diameter leakage point, and each level of detection is performed under the condition of meeting the requirement, so that the detection efficiency is greatly improved while the possibility of misjudgment is effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of airtightness testing technology, and in particular to a hydrogen-nitrogen leak detection system and its leak detection method. Background Technology

[0002] The leak detection principle of a hydrogen-nitrogen leak detector is mainly based on using a mixture of 5% hydrogen and 95% nitrogen as a tracer gas. This mixture fully utilizes the advantages of nitrogen (non-flammable, non-toxic, non-corrosive, safe, and environmentally friendly) and hydrogen (strong diffusion and high escape rate, enabling it to quickly penetrate even the smallest leak paths). In practical use, a highly sensitive hydrogen sensor is required to detect the leak point, and the amount of hydrogen escape detected by the sensor is taken as the actual leak detection result.

[0003] In existing technologies, the above-mentioned leak detection process is usually achieved using a standalone hydrogen-nitrogen leak detector. When the hydrogen-nitrogen leak detector provided by the existing technology is applied to a specific leak detection scenario, it is usually implemented in two forms: sniffing mode or collection mode. In sniffing mode, a mixture of 5% hydrogen and 95% nitrogen gas is introduced into the product under test through a gas port before detection. Then, a handheld probe is used to directly scan the surface of the workpiece to accurately locate the leak point. In collection mode, a corresponding sealed cover is required. The product under test is placed inside the sealed cover, and tracer gas is introduced into the product under test. The size of the leak point and the leak rate information of the product under test are obtained by detecting the changes in hydrogen concentration or pressure inside the sealed cover.

[0004] It should be pointed out that the hydrogen-nitrogen leak detectors provided in the existing technology have obvious defects in practical applications. On the one hand, the environmental noise of the hydrogen-nitrogen leak detectors implemented in sniffing mode has a great impact on the leak detection results in actual applications. If there are other hydrogen sources in the environment, such as electrolysis or chemical emissions, false alarms may occur, and the reliability of the detection results is not strong. In practical applications of hydrogen-nitrogen leak detectors implemented in collection mode, it is easy to infer from the instrument settings and detection process that although the sealed cover isolates the product under test from the external environment, the external ambient gas that initially entered remains inside the sealed cover after the product is placed inside. As a result, the collection mode will also face the problem of environmental noise affecting the leak detection results, similar to the sniffing mode. At the same time, because of the external ambient gas remaining inside the sealed cover, when hydrogen-nitrogen gas is introduced into the product under test, if there is a leak, the hydrogen-nitrogen gas introduced into the product under test will escape through the leak into the test cover. The external ambient gas remaining inside the sealed cover will dilute the escaped hydrogen-nitrogen gas, and the hydrogen-nitrogen gas in the test cover often needs to wait a long time to accumulate to a measurable concentration level, which seriously slows down the detection efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a hydrogen-nitrogen leak detection system and method with more reliable detection results and higher detection efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A hydrogen-nitrogen leak detection system, comprising:

[0008] The test enclosure has internal space to accommodate the product being tested.

[0009] A vacuum module is connected to the test chamber. The vacuum module can be started and stopped as needed to evacuate or break the vacuum in the internal space of the test chamber.

[0010] And a hydrogen-nitrogen leak detection module, which is connected to the product under test. The hydrogen-nitrogen leak detection module can be started and stopped as needed to detect the escape of tracer gas from the product under test.

[0011] Optionally, the vacuum module includes a negative pressure source, a vacuum valve, and a pressure gauge; the vacuum valve is located between the negative pressure source and the test chamber and connects the two; the pressure gauge is located inside the test chamber and is fixedly connected to the test chamber.

[0012] Optionally, the vacuum module further includes a vacuum breaking valve, which is located outside the test cover, with one end connected to the test cover and the other end connected to the external atmospheric environment.

[0013] Optionally, the hydrogen-nitrogen leak detection module includes a leak detector, a hydrogen-nitrogen gas source, and a hydrogen probe; the hydrogen-nitrogen gas source is detachably connected to the product under test via the leak detector, the probe of the hydrogen probe extends into the test cover, and the hydrogen probe interacts with the leak detector to report real-time hydrogen concentration data to the leak detector.

[0014] Optionally, the hydrogen-nitrogen leak detection module further includes a gas supply pipe, an exhaust pipe, and an inflation pipe; the gas supply pipe is disposed between the hydrogen-nitrogen gas source and the leak detector to connect the two; the exhaust pipe is disposed between the leak detector and the exhaust port of the product currently being tested to connect the two; and the inflation pipe is disposed between the leak detector and the inflation port of the product currently being tested to connect the two.

[0015] This invention also provides a hydrogen-nitrogen leak detection method, which is based on the hydrogen-nitrogen leak detection system described above and includes:

[0016] S1. Place the product to be tested into the test cover and connect the hydrogen-nitrogen leak detection module to the product to be tested;

[0017] S2. Vacuum the inside of the product under test to determine if there is a large-diameter leak. If there is, jump to S5; otherwise, jump to S3.

[0018] S3. Evacuate the inside of the test chamber;

[0019] S4. Fill the product under test with hydrogen and nitrogen gas, and detect the change in hydrogen concentration inside the test chamber to determine the current leakage rate of the product under test.

[0020] S5. Open the test cover, take out the product under test, and record its leakage and test data.

[0021] Optionally, S1 specifically involves: connecting the hydrogen-nitrogen gas source and the leak detector via the gas supply pipe; loading the product under test into the test hood; connecting the leak detector and the exhaust port of the product under test via the exhaust pipe; and connecting the leak detector and the inflation port of the product under test via the inflation pipe.

[0022] Optionally, S2 specifically involves: the leak detector presets a first vacuum threshold and a first time threshold; the leak detector evacuates the inside of the product under test through the exhaust pipe; if the vacuum level inside the product under test cannot reach the first vacuum threshold level within the first time threshold, it is determined that the product under test has a large-diameter leak and the process jumps to S5; otherwise, it jumps to S3.

[0023] Optionally, S3 specifically involves: setting a second vacuum threshold, opening the vacuum valve, connecting the test hood to the negative pressure source, continuously evacuating the internal space of the test hood with the negative pressure source, observing the real-time data of the pressure gauge, and closing the vacuum valve when the real-time data of the pressure gauge reaches the second vacuum threshold.

[0024] Alternatively, a second time threshold is preset, and the vacuum valve is opened within the second time threshold to connect the test cover with the negative pressure source, so that the negative pressure source continuously evacuates the internal space of the test cover.

[0025] Optionally, S4 specifically involves: setting a preset hydrogen-nitrogen pressure threshold; the hydrogen-nitrogen source sequentially injecting a hydrogen-nitrogen mixture into the product under test along the gas supply pipe, leak detector, and filling pipe; after the product under test reaches the hydrogen-nitrogen pressure threshold level at the start of filling, the hydrogen probe inserted into the test hood is used to detect the change data of hydrogen concentration inside the test hood.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] The hydrogen-nitrogen leak detection system and method provided by this invention, by introducing a test hood and using a vacuum module to artificially construct a vacuum environment, can flexibly cope with the detection needs under different pressure environments, eliminate the interference of environmental noise on the leak detection results, and significantly improve the accuracy and single-pass leak detection speed of the leak detection process. Furthermore, the leak detection method provided by this invention, through a hierarchical judgment mechanism, only detects the leak rate of the tested product after ensuring that there are no large-diameter leaks. Each level of detection is performed under compliant conditions, thereby effectively reducing the possibility of false judgments and greatly improving detection efficiency. This provides a more ideal solution for airtightness testing in various industrial scenarios. Attached Figure Description

[0028] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings, wherein:

[0029] Figure 1 This is a schematic diagram of the hydrogen-nitrogen leak detection system provided in this specific embodiment.

[0030] Figure 2 This is a system flowchart of the hydrogen-nitrogen leak detection method provided in this specific embodiment. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0032] Please see Figure 1 This specific embodiment provides a hydrogen-nitrogen leak detection system, including a test hood, a vacuum module, a hydrogen-nitrogen leak detection module, and a pressure gauge;

[0033] The test cover has an internal space and is designed and manufactured as an openable structure. Technicians can open the test cover to take out and put in the product under test, or close it to create a sealed space inside the test cover.

[0034] The vacuum module is connected to the test chamber. The vacuum module can be started and stopped as needed to evacuate or break the vacuum in the internal space of the test chamber. The vacuum module works according to the different test process requirements to change the vacuum level in the internal space of the test chamber.

[0035] The hydrogen-nitrogen leak detection module is connected to the product under test. The module can be started and stopped as needed to detect the escape of tracer gas from the product under test. The module is inserted into the test chamber. Before starting the test, the technician must first open the test chamber, place the product under test in its internal space, connect the hydrogen-nitrogen leak detection module to the product under test, and then close the test chamber to complete the preparation and start the testing process.

[0036] In this specific embodiment, the vacuum module includes a negative pressure source, a vacuum pump, and a vacuum breaking valve. The vacuum pump is located between the negative pressure source and the test chamber, connecting the two. The vacuum breaking valve is located outside the test chamber, with one end connected to the test chamber and the other end connected to the external atmosphere. That is, in this specific embodiment, the vacuum module serves to create a test environment by evacuating the closed test chamber and to break the vacuum after the test is completed, facilitating technicians to open the test chamber and remove the tested product. The vacuuming process involves the negative pressure source, the vacuum pump, and the test chamber connected sequentially. The negative pressure source uses the vacuum pump to remove gas from the test chamber, eliminating interference from environmental factors on the leak detection results. After the test is completed, the vacuum breaking valve opens, reconnecting the test chamber to the external atmosphere, increasing the internal air pressure of the test chamber, and facilitating technicians to open the test chamber and remove the tested product.

[0037] In this specific embodiment, the hydrogen-nitrogen leak detection module includes a leak detector, a hydrogen-nitrogen gas source, a hydrogen probe, a gas supply pipe, an exhaust pipe, and a filling pipe. The hydrogen-nitrogen gas source is detachably connected to the product under test via the leak detector. The probe of the hydrogen probe extends into the test hood, and the hydrogen probe interacts with the leak detector to report real-time hydrogen concentration data. The gas supply pipe is located between the hydrogen-nitrogen gas source and the leak detector to connect the two. The exhaust pipe is located between the leak detector and the exhaust port of the product under test to connect the two. The filling pipe is located between the leak detector and the filling port of the product under test to connect the two. The hydrogen-nitrogen gas source stores sufficient hydrogen-nitrogen mixture, which is a mixture of 5% hydrogen and 95% nitrogen. The hydrogen-nitrogen gas source is always connected to the leak detector via the gas supply pipe, and the leak detector is always connected to one end of the filling pipe. The other end of the inflation pipe extends into the test chamber. Before starting the test, as mentioned earlier, after opening the test chamber and placing the product under test inside, the technician needs to connect the inflation port of the product under test to the end of the inflation pipe furthest from the leak detector. This allows the hydrogen-nitrogen mixture stored in the hydrogen-nitrogen source to be sequentially supplied through the gas supply pipe, leak detector, and inflation pipe into the internal cavity of the product under test, establishing a gas path between the hydrogen-nitrogen source and the internal space of the product under test. This facilitates the filling of the product with the hydrogen-nitrogen mixture according to the test requirements during the test. The leak detector is also always connected to one end of the exhaust pipe, the other end of which also extends into the test chamber. Before starting the test, the technician needs to connect the exhaust port of the product under test to the end of the exhaust pipe furthest from the leak detector. After completing the test, the technician must open the test chamber and disconnect both the inflation and exhaust pipes from the product under test before removing it. The hydrogen detector's test head is equipped with a high-precision, high-sensitivity hydrogen sensor. When the test head is inserted into the test chamber, the sensor sensitively detects changes in the surrounding hydrogen concentration. The detector converts this concentration into an electrical signal, which is then fed back to the leak detector to report real-time hydrogen concentration data. The leak detector reads this data and analyzes the hydrogen and nitrogen escape from the tested product based on the detector's readings. It then analyzes and calculates the leak rate, presenting the real-time results to technicians for their assessment or reporting the data to a higher-level computer.

[0038] The leak detector described in this specific embodiment is prior art. It has the ability to controllably and selectively connect or disconnect the gas path channel of hydrogen-nitrogen gas source-filling pipe-leak detector-filling pipe-internal cavity of the tested product; controllably and selectively connect or disconnect the gas path channel of internal cavity of the tested product-exhaust pipe-leak detector-external environment; detect the pressure of the internal cavity of the currently connected tested product in real time; and controllably read / analyze / display / report the real-time hydrogen concentration data returned by the hydrogen probe to an external host computer. When those skilled in the art implement the technical solution provided in this specific embodiment and apply it to a specific product leak detection scenario, they can choose an existing, mature hydrogen-nitrogen leak detection system that meets the actual parameter requirements of the current batch of products, depending on the specific circumstances. The specific internal structure and working principle of the leak detector are not the core of protection of this application and are not within the scope of protection claimed in this application.

[0039] In practical applications, the leak detector will integrate a pressure sensor, flow meter, or other instruments that can be used to observe its internal storage and output. Technicians can select a mature, suitable, and easy-to-use hydrogen and nitrogen gas source according to actual testing needs to implement the technical solution provided in this specific embodiment.

[0040] In this specific embodiment, a pressure gauge is also included. The pressure gauge is installed inside the test chamber and is fixedly connected to the test chamber. The pressure gauge installed here can be used to observe the real-time pressure changes inside the test chamber. In specific implementation, technicians can use wired transmission, wireless communication or other methods to synchronously obtain the real-time information of the pressure gauge outside the test chamber.

[0041] Please see Figure 2 In this specific embodiment, a hydrogen-nitrogen leak detection method is also provided. This hydrogen-nitrogen leak detection method is based on the hydrogen-nitrogen leak detection system described above and includes:

[0042] S1. Preparation: Place the product under test into the test chamber and connect the hydrogen-nitrogen leak detection module to the product under test. Specifically, place the product under test into the test chamber, connect the hydrogen-nitrogen gas source to the leak detector via the gas supply pipe, connect the leak detector to the exhaust port of the product under test via the exhaust pipe, and connect the leak detector to the inflation port of the product under test via the inflation pipe. Then, the technician closes the test chamber, shuts off the vacuum valve and vacuum breaking valve in the vacuum module, and simultaneously disconnects the inflation and exhaust pipes of the leak detector, sealing the product under test. At this point, the test chamber is also sealed, thus completing the preparation for a single leak test of a single product under test.

[0043] S2. Vacuum the inside of the product under test to determine if there is a large-diameter leak. That is, the leak detector presets a first vacuum threshold and a first time threshold. The leak detector evacuates the inside of the product under test through the exhaust pipe. If the vacuum inside the product under test cannot reach the first vacuum threshold level within the first time threshold, it can be reasonably determined that there is a large-diameter leak. It is because of the existence of the above-mentioned large-diameter leak that the internal cavity of the product under test cannot be clearly isolated from the external space of the product - the space inside the test chamber. The gas in the two spaces can flow freely through the above-mentioned large-diameter leak. Once a product under test has a large-diameter leak, there is no need to continue testing the product under test. The product under test can be directly identified as a defective product, and the process can be directly skipped to S5 to detect it separately and mark and classify it.

[0044] S3: Evacuate the inside of the test chamber; that is, preset the second vacuum threshold, open the vacuum valve, connect the test chamber to the negative pressure source, and continuously evacuate the internal space of the test chamber with the negative pressure source, observe the real-time data of the pressure gauge, and close the vacuum valve when the real-time data of the pressure gauge reaches the second vacuum threshold.

[0045] Alternatively, a second time threshold can be preset, and the vacuum valve can be opened within the second time threshold to connect the test cover with the negative pressure source, so that the negative pressure source can continuously evacuate the internal space of the test cover.

[0046] If the product under test successfully passes step S2, it indicates that the product does not have a large-diameter leak. At this point, a second vacuum level is preset, the vacuum valve is opened, and the test chamber is connected to the negative pressure source. The negative pressure source continuously evacuates the internal space of the test chamber, and the real-time data of the pressure gauge is observed. When the real-time data of the pressure gauge reaches the vacuum threshold, the vacuum valve is closed. With the cooperation of the vacuum valve, the negative pressure source evacuates the test chamber, expelling all the air remaining outside the product under test and inside the test chamber. This avoids interference from other gases in the environment that could affect the detection process and results. Furthermore, after completing step S3, there is no excess gas in the internal space of the test chamber, which helps to prevent excess gas from diluting the hydrogen and nitrogen gas and affecting the overall detection accuracy in the subsequent step S4.

[0047] The specific execution process of step S3 can also help technicians check whether the currently operating hydrogen-nitrogen leak detection system meets the detection requirements. By setting a second time threshold and a second vacuum threshold, since the test chamber is currently in a closed state, the second time threshold is used as the specified observation time window, and the second vacuum threshold is used as the observation benchmark. If, within this observation window, the real-time data change detected by the pressure gauge consistently fails to reach the second vacuum threshold level, it can be reasonably determined that there is a leak in the test chamber or other system components. The test environment required for the leak detection process cannot be constructed at all, and there is always a gas channel between the internal space of the test chamber and the external environment. Air from the external environment can continuously enter the test chamber through the leak on the test chamber. In this case, technicians should immediately stop the test process, re-inspect each component within the test system, pay attention to troubleshooting and repair, and avoid wasting detection resources by blindly starting the test while ignoring the risk of leakage in the system itself.

[0048] S4. Inject hydrogen and nitrogen gas into the product under test and detect changes in hydrogen concentration within the test chamber to determine the current leak rate. Specifically, a preset hydrogen and nitrogen pressure threshold is established. The hydrogen and nitrogen gas source sequentially injects a hydrogen-nitrogen mixture into the product under test through the supply pipe, leak detector, and filling pipe. After the product reaches the hydrogen and nitrogen pressure threshold level, a hydrogen gas probe inserted into the test chamber is used to detect changes in hydrogen concentration. As explained above, in step S2, a vacuum is drawn inside the product under test to check for large-diameter leaks and simultaneously remove air from the internal cavity. After entering step S3, the product under test is in a pure state, almost free of air. Since step S3 involves evacuating the test chamber to remove air from both the outside and inside of the test chamber, step S4 results in a vacuum both inside and outside the product under test. In this state, injecting hydrogen and nitrogen gas into the product without diluting it with air will result in leaks. The concentration of hydrogen and nitrogen inside the tested product changes very rapidly. If the tested product has a small-diameter leak, the hydrogen and nitrogen gas that is filled into the internal cavity of the tested product will escape from the leak. Since the space inside the test chamber and outside the tested product is usually in a vacuum state at this time, without background noise and air dilution, the concentration of hydrogen and nitrogen gas inside the test chamber and outside the tested product also changes rapidly. The hydrogen gas detector can capture this concentration change in time and report the concentration change data to the leak detector in a timely manner to record and calculate the current leak rate of the tested product. As can be seen from the above process, since the internal cavity of the product under test is already in a vacuum state before entering step S4, introducing a small amount of hydrogen or nitrogen gas into the product under test can cause a drastic change in the gas concentration inside the product. Furthermore, since the inside of the test chamber and the outside of the product under test are also in a vacuum state, the hydrogen and nitrogen gas escaping through the small-diameter leak point eliminates the influence of environmental noise on the test results and avoids the dilution effect of residual gas. It also causes a drastic change in gas concentration in the space inside the test chamber and outside the product under test. The hydrogen probe can conveniently, accurately, and efficiently capture the concentration change data and report it to the leak detector, greatly improving the detection accuracy and speed.

[0049] Technicians can use existing leakage rate determination standards to calculate the leakage rate of the tested product. The technical solution provided in this specific embodiment supports either direct concentration determination or leakage rate determination. Concentration determination is in ppm, measured by a hydrogen sensor built into the test head of the hydrogen probe, which measures the change in concentration from the start to the end of the detection time. For example, if the concentration determination value is set to 0.5 ppm and the detection time is 60 seconds, a 1 ppm increase in concentration at the end of the test indicates a product leak (1 ppm > 0.5 ppm). However, if leakage rate determination is used, the leakage rate is calculated based on the difference between the internal volume of the test chamber and the volume of the tested product in the preceding process of the hydrogen-nitrogen leak detection system. This is based on the change in hydrogen concentration inside the test chamber measured by the hydrogen probe and the hydrogen-nitrogen filling time. The specific leakage rate calculation formula and its parameter settings are existing technologies, which can be obtained by those skilled in the art through consulting current national standards, relevant journal articles, or other technical materials. The specific calculation process of the leakage rate is not the core of this application.

[0050] S5. Break the vacuum in the test chamber, remove the product under test, and record its test data. Before breaking the vacuum in the test chamber, the hydrogen-nitrogen mixture that was filled into the product under test in the previous process can be extracted to prevent the hydrogen-nitrogen mixture from remaining in the product under test and affecting its specific use.

[0051] The hydrogen-nitrogen leak detection method provided in this specific embodiment isolates the product under test from the external environment by setting up a test hood. Before starting the test, a vacuum is created inside the test hood and outside the product under test using a negative pressure source. On the one hand, if a vacuum environment can be successfully established inside the test hood and outside the product under test, it can be inferred that there is an oversized leak in the current test hood, the product under test, or other components of the test system. In this case, the current leak detection environment cannot be established at all, and technicians should immediately terminate the test and conduct a detailed inspection of the pipelines or internal structure of the hydrogen-nitrogen leak detection system, or directly determine that the current product under test is defective and discard it. On the other hand, if a vacuum environment with the required vacuum level can be successfully created inside the test hood and outside the product under test, it can be inferred that the current test hood, the product under test, or other components of the test system meet the pre-leak detection requirements. At the same time, the vacuuming operation inside the test hood will also effectively eliminate the influence of gases mixed in with the environment on the leak detection results.

[0052] The technical solution provided in this specific embodiment is applicable to negative pressure testing scenarios. By independently constructing a vacuum environment for each product under test, it provides a more reliable and efficient leak detection solution.

[0053] The technical solutions disclosed in the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only applicable to help understand the uninterruptible power supply and its core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A hydrogen-nitrogen leak detection system, characterized in that, include: The test enclosure has internal space to accommodate the product being tested. A vacuum module is connected to the test chamber. The vacuum module can be started and stopped as needed to evacuate or break the vacuum in the internal space of the test chamber. And a hydrogen-nitrogen leak detection module, which is connected to the product under test. The hydrogen-nitrogen leak detection module can be started and stopped as needed to detect the escape of tracer gas from the product under test.

2. The hydrogen-nitrogen leak detection system as described in claim 1, characterized in that, The vacuum module includes a negative pressure source, a vacuum valve, and a pressure gauge; the vacuum valve is located between the negative pressure source and the test chamber and connects the two; the pressure gauge is located inside the test chamber and is fixedly connected to the test chamber.

3. The hydrogen-nitrogen leak detection system as described in claim 2, characterized in that, The vacuum module also includes a vacuum breaking valve, which is located outside the test cover, with one end connected to the test cover and the other end connected to the external atmospheric environment.

4. The hydrogen-nitrogen leak detection system as described in claim 1, characterized in that, The hydrogen-nitrogen leak detection module includes a leak detector, a hydrogen-nitrogen gas source, and a hydrogen probe. The hydrogen-nitrogen gas source is detachably connected to the product under test via the leak detector. The probe of the hydrogen probe extends into the test cover, and the hydrogen probe interacts with the leak detector to report real-time hydrogen concentration data to the leak detector.

5. The hydrogen-nitrogen leak detection system as described in claim 4, characterized in that, The hydrogen-nitrogen leak detection module also includes a gas supply pipe, an exhaust pipe, and an inflation pipe; the gas supply pipe is located between the hydrogen-nitrogen gas source and the leak detector to connect the two; the exhaust pipe is located between the leak detector and the exhaust port of the product currently being tested to connect the two; and the inflation pipe is located between the leak detector and the inflation port of the product currently being tested to connect the two.

6. A hydrogen-nitrogen leak detection method, said hydrogen-nitrogen leak detection method being based on the hydrogen-nitrogen leak detection system as described in any one of claims 1-5, characterized in that, include: S1. Place the product to be tested into the test cover and connect the hydrogen-nitrogen leak detection module to the product to be tested; S2. Vacuum the inside of the product under test to determine if there is a large-diameter leak. If there is, jump to S5; otherwise, jump to S3. S3. Evacuate the inside of the test chamber; S4. Fill the product under test with hydrogen and nitrogen gas, and detect the change in hydrogen concentration inside the test chamber to determine the current leakage rate of the product under test. S5. Open the test cover, take out the product under test, and record its leakage and test data.

7. The hydrogen-nitrogen leak detection method as described in claim 6, characterized in that, Specifically, S1 involves: connecting the hydrogen-nitrogen gas source and the leak detector via the gas supply pipe; loading the product under test into the test hood; connecting the leak detector and the exhaust port of the product under test via the exhaust pipe; and connecting the leak detector and the inflation port of the product under test via the inflation pipe.

8. The hydrogen-nitrogen leak detection method as described in claim 6, characterized in that, Specifically, S2 is as follows: the leak detector presets a first vacuum threshold and a first time threshold. The leak detector evacuates the inside of the product under test through the exhaust pipe. If the vacuum level inside the product under test cannot reach the first vacuum threshold level within the first time threshold, it is determined that there is a large-diameter leak in the product under test, and the process jumps to S5; otherwise, it jumps to S3.

9. The hydrogen-nitrogen leak detection method as described in claim 6, characterized in that, S3 specifically involves: setting a second vacuum threshold, opening the vacuum valve, connecting the test hood to the negative pressure source, continuously evacuating the internal space of the test hood with the negative pressure source, observing the real-time data of the pressure gauge, and closing the vacuum valve when the real-time data of the pressure gauge reaches the second vacuum threshold. Alternatively, a second time threshold is preset, and the vacuum valve is opened within the second time threshold to connect the test cover with the negative pressure source, so that the negative pressure source continuously evacuates the internal space of the test cover.

10. The hydrogen-nitrogen leak detection method as described in claim 7, characterized in that, Specifically, S4 involves: setting a preset hydrogen-nitrogen pressure threshold; sequentially filling the product under test with a hydrogen-nitrogen mixture through the gas supply pipe, leak detector, and filling pipe; and after filling the product under test with gas and reaching the hydrogen-nitrogen pressure threshold level, using the hydrogen probe inserted into the test hood to detect the change in hydrogen concentration inside the test hood.

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