Gas method test device for penetration piece

Abstract

The embodiment of the utility model provides a gas method test device of a penetration piece, the gas method test device adopts an integrated structure design, all devices are integrated in a box body, and each device comprises an inlet, an outlet, an inlet valve, an outlet valve, a flow measurement loop and a bypass loop. During test, the inlet valve and the outlet valve are opened, test gas enters the box body through the inlet, rapid stamping is performed through the bypass loop at the moment, then the flow of the test gas is measured through the flow measurement loop, and then the test gas is input into the penetration piece to be tested through the outlet for test. Flow measurement of test gas in the test process can be achieved by operating the box body in the whole process, operation is easy, and measurement is more accurate.

Description

Technical Field

[0001] This utility model relates to the field of containment testing technology, and in particular to a gas method testing device for penetration components. Background Technology

[0002] The containment vessel, the third barrier of a nuclear power plant, is cylindrical in shape, sealed at the bottom with reinforced concrete and at the top with a quasi-spherical prestressed dome. The surrounding walls are also composed of prestressed concrete. An internal 6mm thick carbon steel lining is installed to prevent leaks. The containment vessel is 900mm thick and houses various components including: pipes and ventilation ducts for transporting various fluids, cable channels, personnel gates, and equipment gates.

[0003] To ensure the containment function as a third line of defense is not compromised, all test devices penetrating the containment must have appropriate measures in place to ensure that the safety valve isolation signal can close the safety isolation valve in the event of an accident. These facilities constitute the containment isolation test apparatus. At this point, the containment needs to be tested, and containment tests are divided into three categories: A, B, and C.

[0004] Class A tests are overall containment leakage rate tests, Class B tests are containment penetration leakage rate tests, and Class C tests are mechanical penetration sealing tests, verifying the sealing performance of isolation valves that isolate the inside and outside of the containment. For Class C tests, the test medium is generally determined based on the medium flowing within the mechanical penetration pipe; typically, water-based test setups use the water method, and gas-based test setups use the gas method. The test employs localized pressurization, with the pressurization direction generally from inside to outside the containment. The pressure difference across the isolation valve in the penetration is equal to the containment design pressure under a LOCA (Loss of Coolant) accident (4.2 barg). Existing mechanical penetration testing equipment is primarily based on float flowmeters (also known as glass rotor flowmeters) in its overall design. To expand the measurement range, two or three float flowmeters with different ranges are usually designed in parallel, and the measurement range is expanded by switching measurement channels. Currently, most nuclear power plants in China use float flowmeters as the mainstream testing equipment for mechanical penetration tests, which are further divided into water-based and gas-based testing setups depending on the test medium.

[0005] However, the float flowmeter has the following main problems in use: the float flowmeter and the pressurization device (controlling the test pressure) are separate designs, and the entire process requires manual control for equipment connection, range switching, data reading and recording. The operation is complicated and prone to human error, which can lead to incorrect measurement results. Utility Model Content

[0006] This utility model provides a gas method testing device for penetrating parts, which aims to solve the problem that the existing penetrating part testing equipment has a split design, requires manual operation throughout the process, and is prone to errors in measurement results.

[0007] This utility model provides a gas method testing device for penetrating parts, including a housing. The housing is provided with an inlet, an outlet, an inlet valve, an outlet valve, a flow measurement circuit, and a bypass circuit. The input end of the inlet is used to connect to a test gas source, the output end of the inlet is connected to the inlet valve, the outlet valve is connected to the input end of the outlet, and the output end of the outlet is used to connect to the penetrating part to be tested. The flow measurement circuit and the bypass circuit are arranged in parallel between the inlet valve and the outlet valve.

[0008] The flow measurement circuit is used to measure the flow rate of the test gas, and the bypass circuit is used to perform rapid ramming when activated.

[0009] Specifically, the flow measurement circuit includes a first flow circuit and a second flow circuit connected in parallel. The first flow circuit includes a first flow valve and a first flow measuring element connected in series. The second flow circuit includes a second flow valve and a second flow measuring element connected in series. The output end of the inlet valve is connected to both the first flow valve and the second flow valve. The first flow measuring element and the second flow measuring element have different measurement ranges.

[0010] Specifically, the bypass circuit includes a bypass valve, and the output end of the inlet valve is connected to the bypass valve.

[0011] Specifically, the housing is also equipped with a pressure relief port and a pressure relief valve. One end of the pressure relief valve is connected to the input end of the pressure relief port, and the other end of the pressure relief valve is connected between the flow measurement circuit and the outlet valve.

[0012] Specifically, the housing is also equipped with a pressure measuring device, which is connected between the flow measurement circuit and the other end of the pressure relief valve.

[0013] Specifically, the housing is also equipped with a filter, which is located between the output end of the inlet and the inlet valve, and is used to filter impurities in the test gas source.

[0014] Specifically, the chamber is also equipped with a pressure regulating valve, which is located between the inlet valve and the flow measurement circuit, and is used to regulate the pressure of the test gas during the test.

[0015] Specifically, the chamber is also equipped with a temperature measuring device, which is located between the pressure regulating valve and the flow measurement circuit, and is used to measure the temperature of the test gas during the test.

[0016] Specifically, both the first and second flow measurement devices are differential pressure mass flow meters.

[0017] Specifically, both the first flow valve and the second flow valve are SMC vacuum solenoid valves.

[0018] This utility model provides a gas-based testing device for penetrating parts. The device employs an integrated structural design, incorporating all components into a housing. These components include an inlet, an outlet, an inlet valve, an outlet valve, a flow measurement circuit, and a bypass circuit. During testing, the inlet and outlet valves are opened, allowing test gas to enter the housing through the inlet. The gas is then rapidly pressurized via the bypass circuit. The flow measurement circuit then measures the flow rate of the test gas. Subsequently, the test gas is input to the penetrating part under test through the outlet for testing. The entire process allows for flow rate measurement of the test gas simply by operating the housing, resulting in simple operation and more accurate measurements. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the external structure of a gas method testing device for a penetrating component provided in an embodiment of this utility model;

[0021] Figure 2 A schematic diagram of the internal structure of a gas method testing device for a penetrating component provided in the first embodiment of this utility model;

[0022] Figure 3 This is a schematic diagram of the working principle of a gas-based testing device for penetrating components.

[0023] Explanation of the markings in the image:

[0024] 1. Housing; 11. Inlet; 11a. Inlet valve; 12. Outlet; 12a. Outlet valve; 13. Flow measurement circuit; 131. First flow circuit; 1311. First flow valve; 1312. First flow measuring element; 132. Second flow circuit; 1321. Second flow valve; 1322. Second flow measuring element; 14. Bypass circuit; 141. Bypass valve; 15. Pressure relief port; 15a. Pressure relief valve; 16. Pressure measuring element; 17. Filter; 18. Pressure regulating valve; 19. Temperature measuring element; 20. Display screen. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0026] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0027] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0028] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0029] Please see Figure 1-3 This utility model provides a gas method testing device for penetrating parts, including a housing 1. The housing 1 is provided with an inlet 11, an outlet 12, an inlet valve 11a, an outlet valve 12a, a flow measurement circuit 13, and a bypass circuit 14. The input end of the inlet 11 is used to connect to the test gas source, the output end of the inlet 11 is connected to the inlet valve 11a, the outlet valve 12a is connected to the input end of the outlet 12, and the output end of the outlet 12 is used to connect to the penetrating part to be tested. The flow measurement circuit 13 and the bypass circuit 14 are arranged in parallel between the inlet valve 11a and the outlet valve 12a.

[0030] The flow measurement circuit 13 is used to measure the flow rate of the test gas, and the bypass circuit 14 is used to perform rapid ramming when it is turned on.

[0031] In this embodiment, the gas testing device adopts an integrated structural design, integrating all components into the housing 1. These components include an inlet 11, an outlet 12, an inlet valve 11a, an outlet valve 12a, a flow measurement circuit 13, and a bypass circuit 14. The housing 1 also has a control board for collecting and processing measurement data and transmitting it to a display screen 20. The display screen 20 allows for control of the housing 1 during testing, making the testing operation more convenient as only the housing 1 needs to be operated. In specific implementation, the test gas source provides the test gas. The housing 1 is made of hollow aluminum profile for high strength and light weight. Two working circuits are installed inside the housing 1: the flow measurement circuit 13 and the bypass circuit 14. The flow measurement circuit 13 measures the flow rate of the test gas, while the bypass circuit 14 is used for rapid pressing upon activation. Both working circuits can be connected using 8*5.5mm polyether PU gas supply pipes, and the interfaces can be connected using 8mm quick connectors. Inlet 11 and outlet 12 are located on both sides of chamber 1. Both inlet 11 and outlet 12 can use Staubli RBE06 series quick-connect couplings. Inlet 11 is used to connect to the test gas source, and outlet 12 is used to connect to the penetrating component to be tested. Inlet valve 11a and outlet valve 12a are designed on chamber 1 respectively. These two valves are manually controlled ball valves (using Swagelok SS-40 series manual ball valves) for manually opening and closing inlet 11 and outlet 12. Refer to the working principle diagram of the test device. Figure 3 .

[0032] During the test, inlet valve 11a and outlet valve 12a are opened, and the test gas enters the chamber 1 through inlet 11. At this time, it is rapidly pressurized through bypass circuit 14. Then, the flow rate of the test gas is measured through flow measurement circuit 13. Subsequently, the test gas is input to the penetration component under test through outlet 12 for testing. The entire process can be achieved by operating chamber 1 to measure the flow rate of the test gas during the test, which is simple to operate and provides more accurate measurements.

[0033] Specifically, such as Figure 3 As shown, the flow measurement circuit 13 includes a first flow circuit 131 and a second flow circuit 132 connected in parallel. The first flow circuit 131 includes a first flow valve 1311 and a first flow measuring element 1312 connected in series. The second flow circuit 132 includes a second flow valve 1321 and a second flow measuring element 1322 connected in series. The output end of the inlet valve 11a is connected to both the first flow valve 1311 and the second flow valve 1321. The first flow measuring element 1312 and the second flow measuring element 1322 have different measurement ranges.

[0034] In this embodiment, the first flow loop 131 and the second flow loop 132 can be configured according to flow measurement requirements. Specifically, the first flow loop 131 and the second flow loop 132 can be configured as small flow loops or large flow loops according to the measurement range of the corresponding flow measuring devices. In specific implementation, the measurement range of the first flow measuring device 1312 can be 2.5-500 ml / min, and the measurement range of the second flow measuring device 1322 can be 60-12000 ml / min. In this case, the first flow loop 131 is configured as a small flow loop, and the second flow loop 132 is configured as a large flow loop. Then, the corresponding flow valve and flow measuring device are connected in series to ensure that the test gas flows through the flow valve and flow measuring device sequentially. The measurement ranges of the two flow measuring devices can be adjusted to make one flow loop a small flow loop and the other a large flow loop.

[0035] The control board controls the switching between the first flow loop 131 and the second flow loop 132. During testing, the control board automatically switches between loops based on the current flow rate. When measuring, the higher flow loop (i.e., the second flow loop 132) is prioritized. When the detected flow rate is ≤120 ml / min, the testing device automatically switches to the first flow loop 131 and closes the second flow loop 132 (i.e., closes the second flow valve 1321). At this time, the first flow loop 131 is used for flow measurement. If the flow rate increases, when it reaches ≥240 ml / min, the testing device automatically switches to the second flow loop 132 and closes the first flow loop 131 (i.e., closes the first flow valve 1311). At this time, the first flow loop 131 is used for flow measurement. The switching design of these two flow loops has a 120 ml / min redundancy, effectively avoiding repeated switching due to flow fluctuations near the switching value.

[0036] In this embodiment, the measurement ranges of the first flow measuring element 1312 and the second flow measuring element 1322 are set differently, allowing the testing device to be optimized for both large and small flow rates. Taking the first flow loop 131 as a small flow loop and the second flow loop 132 as a large flow loop as an example, under large flow conditions, the second flow measuring element 1322 can accurately measure a wider range of flow changes, avoiding inaccurate measurements or damage to the measuring equipment due to an insufficient range. Under small flow conditions, the first flow measuring element 1312 can accurately measure minute flow changes, meeting the precise control requirements for small flow rates in production processes. This phased and targeted measurement method improves the measurement accuracy of the entire flow measurement loop.

[0037] Specifically, such as Figure 3 As shown, the bypass circuit 14 includes a bypass valve 141, and the output end of the inlet valve 11a is connected to the bypass valve 141.

[0038] In this embodiment, the bypass circuit 14 is used for rapid stamping during the through-hole test, and is operated via a corresponding switch button on the display screen 20. During the test, the test gas enters the test device through the quick connector of the inlet 11. At this time, the inlet valve 11a, outlet valve 12a, and bypass valve 141 are manually opened, and rapid stamping is performed. After stamping is completed, the bypass valve 141 is closed. Then, the flow valve of the corresponding flow circuit is automatically opened according to the flow rate of the test gas. When the test gas passes through the first flow circuit 131 or the second flow circuit 132, the corresponding flow measuring device measures the current flow value and transmits the value to the display screen 20 for display.

[0039] Specifically, such as Figure 1-3 As shown, the housing 1 is also equipped with a pressure relief port 15 and a pressure relief valve 15a. One end of the pressure relief valve 15a is connected to the input end of the pressure relief port 15, and the other end of the pressure relief valve 15a is connected between the flow measurement circuit 13 and the outlet valve 12a.

[0040] In this embodiment, the pressure relief port 15 is the same as the inlet 11 and outlet 12, and can also use a Staubli RBE06 series quick-connect coupling. A pressure relief valve 15a is designed on the housing 1. This valve is also a manually controlled ball valve, and a Swagelok SS-40 series manual ball valve can be used. The pressure relief port 15 and outlet 12 are located on the same side of the housing 1 to relieve the high test pressure during the test. After the test gas is depressurized to meet the test pressure, it goes to outlet 12 through outlet valve 12a and is used to test the penetration component to be tested.

[0041] Specifically, such as Figure 1-3 As shown, a pressure measuring element 16 is also provided on the housing 1. The pressure measuring element 16 is connected between the flow measurement circuit 13 and the other end of the pressure relief valve 15a.

[0042] In this embodiment, the pressure measuring device 16 uses a PMS132 pressure sensor, which features high precision and high stability, with a detection accuracy of ±0.25% (FS). It is used to measure the pressure of the test gas during the test and displays the real-time test pressure on the display screen 20. If the pressure is too high, the pressure relief valve 15a is opened to relieve pressure through the pressure relief port 15, thereby ensuring the test proceeds smoothly according to the procedure. The parameters of the pressure sensor can be found in Table 1.

[0043]

[0044] Table 1

[0045] In Table 1, RS485 is the electrical interface standard, Modbus is an application layer communication protocol, and RTU is one of the transmission modes of this communication protocol.

[0046] Specifically, such as Figure 2-3 As shown, a filter 17 is also provided on the housing 1. The filter 17 is located between the output end of the inlet 11 and the inlet valve 11a and is used to filter impurities in the test gas source.

[0047] In this embodiment, to prevent impurities such as water and oil that may be present in the test gas source from entering the test device, an air filter (filter 17) is preferably installed between the output end of inlet 11 and inlet valve 11a to filter liquids and particles smaller than 5μm, ensuring the cleanliness of the test gas source and protecting the components inside the housing 1. The parameters of the air filter can be found in Table 2.

[0048]

[0049]

[0050] Table 2

[0051] Specifically, such as Figure 1-3 As shown, a pressure regulating valve 18 is also provided on the housing 1. The pressure regulating valve 18 is located between the inlet valve 11a and the flow measurement circuit 13 and is used to regulate the pressure of the test gas during the test.

[0052] In this embodiment, the pressure regulating valve 18 adopts a mechanical pressure regulating structure and has an overflow function. The overflow pressure flows out to the outside of the chamber 1 through the pressure relief hole of the pressure regulating valve 18 itself, and has good pressure stabilization performance. In specific implementation, the pressure regulating valve 18 is set on the top side of the chamber 1. This pressure regulating valve 18 is used to regulate the test pressure during the test process, and the regulation range is 0 to 0.85 MPa to ensure that the test is carried out under stable pressure. The parameters of the pressure regulating valve 18 can be referred to in Table 3:

[0053]

[0054] Table 3

[0055] Specifically, such as Figure 2-3 As shown, a temperature measuring element 19 is also provided on the housing 1. The temperature measuring element 19 is located between the pressure regulating valve 18 and the flow measurement circuit 13 and is used to measure the temperature of the test gas during the test.

[0056] In this embodiment, the gas exhibits thermal expansion and contraction characteristics, and its volume and density change with temperature. In the flow measurement loop 13, temperature fluctuations significantly affect the measurement results. A temperature measuring element 19 is positioned between the pressure regulating valve 18 and the flow measurement loop 13, enabling real-time acquisition of the gas temperature entering the loop. Based on the real-time temperature data, the flow measurement results can be corrected, reducing measurement errors caused by temperature changes and improving the accuracy of the flow measurement. The temperature measuring element 19 can be a PT100 temperature sensor used to measure the temperature of the test gas during the experiment, ensuring the experiment proceeds smoothly according to the procedures.

[0057] Specifically, both the first flow measurement element 1312 and the second flow measurement element 1322 are differential pressure mass flow meters.

[0058] In this embodiment, the differential pressure mass flow meter exhibits stable measurement performance and high accuracy, with a measurement accuracy of 1.0%FS. It is used to measure the flow rate of the test gas to determine the flow leakage rate and transmits the data to the display screen 20 in real time. By comparing the current leakage rate with the acceptable value in the test specification, it is determined whether the test valve meets the specification requirements. The differential pressure mass flow meter can directly measure the flow rate of the test gas, unaffected by changes in gas temperature, pressure, and density. In practical implementation, even when the gas pressure needs to be adjusted via the pressure regulating valve 18, or when the temperature measuring element 19 detects gas temperature fluctuations, the differential pressure mass flow meter can still accurately measure the gas flow rate, improving the accuracy of flow measurement. The technical specifications of the differential pressure mass flow meter can be found in Table 4.

[0059]

[0060] Table 4

[0061] In Table 4, FS is the maximum flow rate that the mass flow meter can measure; RD is the current actual measurement reading of the mass flow meter; Modbus is an application layer communication protocol, RTU is a transmission mode under this communication protocol, 485 refers to the electrical interface standard; DC is direct current; NPT is American standard pipe thread.

[0062] Specifically, both the first flow valve 1311 and the second flow valve 1321 are SMC vacuum solenoid valves.

[0063] In this embodiment, the first flow valve 1311 and the second flow valve 1321 open and close according to the flow rate detected by the corresponding flow meter. Since the valve opening and closing actions need to be completed in a short time, SMC vacuum solenoid valves are preferably used for both the first flow valve 1311 and the second flow valve 1321. SMC vacuum solenoid valves have extremely fast response speeds, enabling them to complete the opening and closing actions in a short time. During the test, when switching from the second flow circuit 132 to the first flow circuit 131, the second flow valve 1321 can close quickly, while the first flow valve 1311 opens quickly. This rapid response capability reduces flow control lag caused by slow valve action, ensuring that flow measurement can detect flow changes in real time and improving the overall dynamic response performance.

[0064] This utility model embodiment adopts an integrated structural design. The housing 1 integrates electronic components such as flow measuring elements (first flow measuring element 1312 and second flow measuring element 1322), pressure measuring element 16, temperature measuring element 19, solenoid valves (first flow valve 1311 and second flow valve 1321), and pressure regulating valve 18. When conducting penetration tests, the control board of the housing 1 collects and processes the measurement data and transmits the data to the display screen 20 for display. The display screen 20 can be used to control the corresponding test operations of the housing 1, making the operation convenient.

[0065] During operation, the entire gas method testing device has two testing procedures: flow rate testing procedure and pressure drop testing procedure. For the flow rate testing procedure, the test gas enters the chamber 1 through inlet 11, and then the inlet valve 11a and outlet valve 12a are manually opened. The test category "flow rate method" is selected on the display screen 20, and the bypass valve 141 is opened. The temperature measuring element 19 and the pressure measuring element 16 measure the temperature and pressure of the test gas in real time and display the values ​​on the display screen 20. The pressure regulating valve 18 is manually adjusted to the test pressure for rapid pressing. After pressing is completed, the bypass valve 141 is closed and the test device is started. The flow valve of the corresponding flow circuit is automatically opened according to the real-time flow rate. When the test gas passes through the first flow circuit 131 or the second flow circuit 132, the corresponding flow measuring element detects the current flow value and transmits it to the display screen 20 for display.

[0066] For the pressure drop method test procedure, select "pressure drop method" on the display screen 20 to conduct the test, open the bypass valve 141, and the temperature measuring element 19 and pressure measuring element 16 measure the temperature and pressure of the test gas in real time and display the values ​​on the display screen 20. Manually adjust the pressure regulating valve 18 to the test pressure and perform a rapid pressurization. After the pressurization is completed, click to close the bypass valve 141 and click to start the test. At this time, the bypass circuit 14 will be automatically opened, and the first flow circuit 131 and the second flow circuit 132 will be automatically closed. At this time, manually close the inlet valve 11a (that is, close the test gas source) and then follow the procedure to maintain the pressure.

[0067] The entire gas circuit of the testing apparatus is connected and integrated using 8*5.5mm polyether PU tubing, with Legris 8mm quick connectors at the interfaces for easy disassembly and maintenance of internal components. The housing 1 is designed with three working interfaces: inlet 11, pressure relief port 15, and outlet 12. Each of these interfaces is equipped with a manual valve, allowing for manual stopping of the test in case of emergencies, thus improving safety. Preferably, to prevent accidental operation during the test, the test method cannot be switched. For example, the display screen 20 has three function buttons: "Bypass On," "Start Sealing Test," and "Start Test." When any one of these three function buttons is active, the other two buttons are grayed out, preventing them from being selected and thus disabling their corresponding functions, preventing accidental activation.

[0068] The control board within the gas-based testing apparatus for the through-hole component receives and processes pressure, temperature, and flow signals from each measuring component. Based on the circuit diagram, it controls the flow valve to adapt to the flow measurement range. During testing, the pressure regulating valve 18 can be manually controlled to adjust the pressure of the testing apparatus to the test pressure. Furthermore, the display screen 20 communicates with the microcontroller via RS485, enabling human-machine interaction. The input circuit employs optocoupler isolation; for example, the pressure measuring component 16 and temperature measuring component communicate with the control board via serial port or RS-485. The output circuit primarily uses relay-driven outputs, making it more suitable for driving high-power devices such as solenoid valves.

[0069] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A gas-based testing apparatus for penetrating components, characterized in that, The device includes a housing, which is equipped with an inlet, an outlet, an inlet valve, an outlet valve, a flow measurement circuit, and a bypass circuit. The input end of the inlet is used to connect to a test gas source, the output end of the inlet is connected to the inlet valve, the outlet valve is connected to the input end of the outlet, and the output end of the outlet is used to connect to the penetrating component to be tested. The flow measurement circuit and the bypass circuit are arranged in parallel between the inlet valve and the outlet valve. The flow measurement circuit is used to measure the flow rate of the test gas, and the bypass circuit is used to perform rapid ramming when activated.

2. The gas method testing apparatus according to claim 1, characterized in that, The flow measurement circuit includes a first flow circuit and a second flow circuit connected in parallel. The first flow circuit includes a first flow valve and a first flow measuring element connected in series. The second flow circuit includes a second flow valve and a second flow measuring element connected in series. The output end of the inlet valve is connected to both the first flow valve and the second flow valve. The first flow measuring element and the second flow measuring element have different measurement ranges.

3. The gas method testing apparatus according to claim 1, characterized in that, The bypass circuit includes a bypass valve, and the output end of the inlet valve is connected to the bypass valve.

4. The gas method testing apparatus according to claim 1, characterized in that, The housing is also equipped with a pressure relief port and a pressure relief valve. One end of the pressure relief valve is connected to the input end of the pressure relief port, and the other end of the pressure relief valve is connected between the flow measurement circuit and the outlet valve.

5. The gas method testing apparatus according to claim 4, characterized in that, The housing is also equipped with a pressure measuring device, which is connected between the flow measurement circuit and the other end of the pressure relief valve.

6. The gas method testing apparatus according to claim 1, characterized in that, The housing is also equipped with a filter, which is located between the output end of the inlet and the inlet valve to filter impurities in the test gas source.

7. The gas method testing apparatus according to claim 1, characterized in that, The chamber is also equipped with a pressure regulating valve, which is located between the inlet valve and the flow measurement circuit and is used to regulate the pressure of the test gas during the test.

8. The gas method testing apparatus according to claim 7, characterized in that, The chamber is also equipped with a temperature measuring device, which is located between the pressure regulating valve and the flow measurement circuit, and is used to measure the temperature of the test gas during the test.

9. The gas method testing apparatus according to claim 2, characterized in that, Both the first and second flow measurement devices are differential pressure mass flow meters.

10. The gas method testing apparatus according to claim 2, characterized in that, Both the first flow valve and the second flow valve are SMC vacuum solenoid valves.

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