Device and method for rapidly detecting leakage rate of connector flange

Abstract

The invention provides a connector flange leak rate rapid detection device and method. The connector flange leak rate rapid detection device comprises a helium tank, a pressure reducing valve, a spray gun, a passive standard leak hole, a stop valve, a connector, a connector flange, a flange overall leak detection tool, a vacuum corrugated pipe and a helium mass spectrometer leak detector. A cavity is formed in the flange integral leakage detection tool, and a flange interface is formed on the edge of the top of the upward opening; a connector flange to be detected is placed above a flange interface of the flange integral leak detection tool and is in sealed connection with the flange interface, and a connector is inserted into the connector flange to be detected. The helium mass spectrometer leak detector is connected to the interior of the flange integral leak detection tool through a vacuum corrugated pipe; the passive standard leak hole is connected to the interior of the flange integral leak detection tool through a stop valve. The spray gun is connected to the helium tank through the pressure reducing valve, and a nozzle of the spray gun faces the connector. According to the invention, the overall leakage rate of the connector flange can be rapidly detected, the leakage point of the connector flange can be rapidly positioned, and the workload of the leakage rate detection of the connector flange can be reduced.

Description

Technical Field

[0001] This invention belongs to the field of non-destructive testing technology, specifically relating to a rapid detection device and method for connector flange leakage rate. Background Technology

[0002] During vacuum thermal testing of spacecraft, all test cables need to be connected via through-cabin flange connectors to establish continuity between the inside and outside of the spacecraft. Different vacuum thermal tests have different requirements for the specifications and quantity of test connectors. During the test preparation phase, it is often necessary to disassemble and adjust the connectors on the flanges to match the test requirements. To ensure that the flange leakage rate is within acceptable limits after connector adjustment, leak testing is essential.

[0003] Patent document CN103323185A discloses a leak detection test platform and method for flange and disc-type vacuum seals, including upper and lower cavities and a transition cavity. A glass observation window is installed on the top of the upper cavity. The part to be tested is installed between the upper and lower cavities. A gate valve is installed between the lower cavity and the transition cavity. The bottom of the transition cavity is connected to a vacuum pumping system. An inflation pipe is connected to one side of the upper cavity, and the inflation pipe is equipped with a high-vacuum valve and a pressure gauge. It is also connected to a vent pipe and a branch connecting pipe. A vent valve is installed on the vent pipe. The lower end of the branch connecting pipe is connected to the lower cavity. The upper cavity and the transition cavity are connected through a main connecting pipe, and both the main connecting pipe and the branch connecting pipe are equipped with high-vacuum valves. By controlling the opening and closing of each valve, leak detection can be performed on both sides of the part to be tested after a single clamping.

[0004] However, patent document CN103323185A addresses the application of connector flange leak detection in the prior art. Figure 3 The detection method shown uses a vacuum tool to check each connector installed on the flange for leaks. Although this method can obtain the specific leakage rate of each connector, it is time-consuming, cumbersome, requires multiple people to cooperate, and is inefficient.

[0005] To achieve rapid detection of the overall leakage rate of connector flanges and quick location of leak points, thereby reducing the workload of leak detection and improving efficiency, this invention presents a rapid leak detection device and method for connector flanges, solving the aforementioned problems. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a rapid detection device and method for connector flange leakage rate.

[0007] A rapid leak detection device for connector flanges provided by the present invention includes: a helium cylinder, a pressure reducing valve, a spray gun, a passive standard leak hole, a shut-off valve, a connector, a connector flange, an overall flange leak detection fixture, a vacuum bellows, and a helium mass spectrometer leak detector. The flange overall leak detection fixture has an internal cavity with an upward-opening top edge forming a flange interface; the flange to be tested is placed above the flange interface of the flange overall leak detection fixture and is sealed to the flange interface, and the connector is inserted into the flange to be tested; the helium mass spectrometer leak detector is connected to the inside of the flange overall leak detection fixture by a vacuum bellows; the passive standard leak hole is connected to the inside of the flange overall leak detection fixture by a shut-off valve. The spray gun is connected to the helium cylinder by a pressure reducing valve, and the nozzle of the spray gun is oriented towards the connector.

[0008] Preferably, a flange sealing ring is provided between the flange interface and the connector flange of the flange integral leak detection tool.

[0009] Preferably, the connector housing is provided with an isolation helium cover that is sealed to the upper surface of the connector flange.

[0010] Preferably, the isolation helium shroud includes a sealing cover plate, a sealing ring, a stainless steel shroud body, and a rubber sealing gasket; the stainless steel shroud body is tubular and sleeved on the outside of the connector; the stainless steel shroud body and the upper surface of the connector flange are sealed and connected by a rubber sealing gasket; the sealing cover plate is disposed at the top of the stainless steel shroud body, and the sealing cover plate and the stainless steel shroud body are sealed and connected by a sealing ring.

[0011] Preferably, the passive standard leak hole should be selected from models whose leak rate differs from the leak rate index of the connector flange to be tested by less than 25%.

[0012] Preferably, the flange sealing ring is a fluororubber sealing ring with a Shore hardness of 75.

[0013] According to the present invention, a method for detecting leakage rate of a connector flange using a rapid leak detection device includes the following steps: Step S1: Wipe the flange of the connector to be tested clean with anhydrous ethanol and let it stand for 30 minutes. Check the connector for any obvious defects or looseness, and check for scratches on the flange sealing surface. Step S2: Power on the helium mass spectrometer leak detector and warm it up for 30 minutes in standby mode. Connect the helium mass spectrometer leak detector to the flange integrated leak detection fixture through the vacuum bellows. Step S3: Connect the passive standard leak hole to the flange integral leak detection fixture through the shut-off valve, with the shut-off valve in the closed state; Step S4: Place the flange to be tested on the test port of the flange overall leak detection fixture, and tighten the flange sealing ring by its own weight to seal it; Step S5: Start the helium mass spectrometer leak detector in vacuum mode, and record the background value I0 after the helium mass spectrometer leak detector readings stabilize. Step S6: Open the shut-off valve, use the spray gun to spray helium into the passive standard leak hole, and record the calibration value I1 after the helium mass spectrometer leak detector value stabilizes. Step S7: Close the shut-off valve and wait for the helium mass spectrometer leak detector value to drop to the background value. Then, use the spray gun to spray helium into all the connectors of the plug flange and record the helium mass spectrometer leak detector value as I2. Step S8: Process and interpret the overall leakage rate data of the connector flange. If the overall leakage rate Q of the connector flange meets the index requirements, the test ends; if the overall leakage rate of the connector flange does not meet the index requirements, proceed to the next step. Step S9: Perform preliminary rapid location of leaking connectors: Use a spray gun to spray helium onto each connector on the connector flange one by one. Observe and record the numbers of connectors near the spray gun when the helium mass spectrometer leak detector readings rise significantly. Use an isolation helium cover to cover and seal the suspected connectors. Then use the spray gun to spray helium onto the remaining connectors again until the helium mass spectrometer leak detector readings no longer rise significantly. Step S10: After waiting for the helium mass spectrometer leak detector reading to drop to the background value, blow helium gas into the isolation helium hood and record the helium mass spectrometer leak detector reading as I3.

[0014] Preferably, in step S9: The spray gun sprays helium onto each connector for 2 seconds, with a 5-second interval between each.

[0015] Preferably, in step S9: The suspected connector was sealed and isolated using an isolation helium shroud, while the remaining connectors were helium-sprayed.

[0016] Preferably, the formula for calculating the overall leakage rate Q of the connector flange is:

[0017] Where Q0 represents the leakage rate value of passive standard leak hole 4; The formula for calculating the leakage rate of a single connector is:

[0018] Among them, Q x This represents the leakage rate value of a single connector, where x = 1, 2, 3...n, and n is the total number of connectors.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention utilizes a rapid leak detection device for connector flanges to achieve rapid detection of the overall leak rate of connector flanges. If the overall leak rate of the flange is qualified, there is no need to detect the leak of each connector individually; if the overall leak rate of the flange exceeds the standard, a helium shroud is used to quickly locate the leak point of the connector flange, which greatly reduces the workload of connector flange leak rate detection and improves the efficiency of connector flange leak detection. Attached Figure Description

[0020] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the structure of the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of the helium shield of the present invention.

[0022] Figure 3 This is the existing leak detection method.

[0023] The diagram shows: 1. Helium cylinder; 2. Pressure reducing valve; 3. Spray gun; 4. Passive standard leak hole; 5. Shut-off valve; 6. Flange sealing ring; 7. Helium isolation cover; 8. Connector; 9. Connector flange; 10. Flange overall leak detection fixture; 11. Vacuum bellows; 12. Helium mass spectrometer leak detector; 13. Sealing cover; 14. Sealing ring; 15. Stainless steel cover; 16. Rubber sealing gasket. Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0025] like Figure 1 , Figure 2 As shown, a rapid leak detection device for connector flanges includes: a helium cylinder 1, a pressure reducing valve 2, a spray gun 3, a passive standard leak hole 4, a shut-off valve 5, a connector 8, a connector flange 9, a flange overall leak detection fixture 10, a vacuum bellows 11, and a helium mass spectrometer leak detector 12.

[0026] The flange leak detection fixture 10 has an internal cavity with an upward-opening top edge forming a flange interface. The flange to be tested, 9, is placed above the flange interface of the flange leak detection fixture 10 and sealed to it. The connector 8 is inserted into the flange to be tested, 9. The helium mass spectrometer leak detector 12 is connected to the inside of the flange leak detection fixture 10 via a vacuum bellows 11. The passive standard leak hole 4 is connected to the inside of the flange leak detection fixture 10 via a shut-off valve 5. The spray gun 3 is connected to the helium cylinder 1 via a pressure reducing valve 2, with the nozzle facing the connector 8.

[0027] The working principle of this application is as follows: a helium mass spectrometer leak detector 12 is connected to a flange overall leak detection fixture 10. The flange 9 of the connector to be tested is sealed to the flange overall leak detection fixture 10 to form a closed detection system, ensuring the reliability of the system's baseline seal. The spray gun 3 provides tracer helium, and the passive standard leak hole 4 is used for instrument calibration, thus making the installation of the experimental equipment convenient and reliable. First, helium is sprayed through the passive standard leak hole 4 to calibrate the instrument and eliminate instrument errors. Then, helium is sprayed onto all connectors 8 on the connector flange 9, and the helium mass spectrometer leak detector 12 captures the amount of helium leakage in the system to determine whether the overall leak rate is qualified. If it is not qualified, the suspected leak point is initially located by observing the change of instrument values ​​through point-by-point helium spraying. Then, the suspected component is sealed with an isolation helium cover 7 to eliminate other interferences and then tested individually to accurately calculate the leak rate of a single connector 8. Compared with the traditional method of vacuuming and leak testing one by one, this method first tests the whole system to determine its qualification and only locates the unqualified components, greatly reducing the testing time. It does not require multiple people to cooperate and can be operated by a single person.

[0028] Specifically, a flange sealing ring 6 is provided between the flange interface of the flange integral leak detection fixture 10 and the connector flange 9. The connector flange 9 to be tested is sealed by its own weight pressing the flange integral leak detection fixture 10.

[0029] The connector 8 is fitted with an isolation helium cover 7 that is sealed to the upper surface of the connector flange 9. The isolation helium cover 7 includes a sealing cover plate 13, a sealing ring 14, a stainless steel cover body 15, and a rubber sealing gasket 16. The stainless steel cover body 15 is tubular and fitted onto the outside of the connector 8. The stainless steel cover body 15 is sealed to the upper surface of the connector flange 9 by the rubber sealing gasket 16. The sealing cover plate 13 is located at the top of the stainless steel cover body 15, and the sealing cover plate 13 is sealed to the stainless steel cover body 15 by the sealing ring 14.

[0030] In one embodiment, the passive standard leak hole 4 should be selected from models whose leak rate differs from the leak rate index of the connector flange 9 to be tested by less than 25%.

[0031] In one embodiment, the flange sealing ring 6 is a fluororubber sealing ring with a Shore hardness of 75.

[0032] This embodiment also provides a detection method for a rapid leak detection device for connector flanges, used in the aforementioned rapid leak detection device for connector flanges, the steps of which include: Step S1: Wipe the flange 9 of the connector to be tested clean with anhydrous ethanol and let it stand for 30 minutes. Check the connector 8 for any obvious defects or looseness, and check for scratches on the flange sealing surface.

[0033] Step S2: Power on the helium mass spectrometer leak detector 12 and warm it up for 30 minutes in standby mode. Connect the helium mass spectrometer leak detector 12 to the flange integral leak detection fixture 10 through the vacuum bellows 11.

[0034] Step S3: Connect the passive standard leak hole 4 to the flange integral leak detection fixture 10 through the shut-off valve 5, with the shut-off valve 5 in the closed state.

[0035] Step S4: Place the flange 9 to be tested on the test port of the flange overall leak detection fixture 10, and tighten the flange sealing ring 6 by its own weight to seal it.

[0036] Step S5: Start the helium mass spectrometer leak detector 12 in vacuum mode, and record the background value I0 after the value of the helium mass spectrometer leak detector 12 stabilizes.

[0037] Step S6: Open the shut-off valve 5, use the spray gun 3 to spray helium into the passive standard leak hole 4, and record the calibration value I1 after the value of the helium mass spectrometer leak detector 12 stabilizes.

[0038] Step S7: Close the shut-off valve 5, wait for the value of the helium mass spectrometer leak detector 12 to drop to the background value, and then use the spray gun 3 to spray helium into all the connectors 8 of the connector flange 9. Record the value of the helium mass spectrometer leak detector 12 as I2.

[0039] Step S8: Process and interpret the overall leakage rate data of the connector flange 9. If the overall leakage rate Q of the connector flange 9 meets the requirements, the test ends. If the overall leakage rate of the connector flange 9 does not meet the requirements, proceed to the next step. The formula for calculating the overall leakage rate Q of the connector flange 9 is:

[0040] Where Q0 represents the leakage rate value of the passive standard leak hole 4.

[0041] Step S9: Perform preliminary rapid location of leaking connectors 8: Use the spray gun 3 to spray helium onto each connector flange 9 one by one. Observe and record the numbers of connectors 8 near the spray gun 3 when the value of the helium mass spectrometer leak detector 12 increases significantly. Use the isolation helium cover 7 to cover and seal the suspected connectors 8, and use the spray gun 3 to spray helium onto the remaining connectors 8 again until the value of the helium mass spectrometer leak detector 12 no longer increases significantly.

[0042] Preferably, the spray gun 3 sprays helium for each connector 8 for 2 seconds, with an interval of 5 seconds between them.

[0043] Preferably, the suspected connector 8 is covered and sealed with an isolation helium shroud 7, while the remaining connectors 8 are sprayed with helium.

[0044] Step S10: After waiting for the helium mass spectrometer leak detector 12 value to drop to the background value, helium gas is injected into the isolation helium shroud 7, and the value of the helium mass spectrometer leak detector 12 is recorded as I3. The formula for calculating the leak rate of a single connector 8 is:

[0045] Among them, Q x This represents the leakage rate value of a single connector 8, where x = 1, 2, 3...n, and n is the total number of connectors 8.

[0046] This invention utilizes a rapid leak detection device for connector flanges to quickly detect the overall leak rate of connector flanges 9. If the overall leak rate of connector flanges 9 is qualified, there is no need to perform individual leak detection on each connector 8. If the overall leak rate of connector flanges 9 exceeds the standard, a single-point isolation helium shroud 7 is used to isolate and quickly locate the leak point of connector flanges 9, greatly reducing the workload of leak rate detection and improving the leak detection efficiency of connector flanges 9.

[0047] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0048] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A rapid detection device for connector flange leakage rate, characterized in that, include: Helium cylinder (1), pressure reducing valve (2), spray gun (3), passive standard leak hole (4), shut-off valve (5), connector (8), connector flange (9), flange overall leak detection fixture (10), vacuum bellows (11) and helium mass spectrometer leak detector (12); The flange integral leak detection fixture (10) forms a cavity inside and forms a flange interface at the top edge of the opening facing upward; the connector flange (9) to be tested is placed above the flange interface of the flange integral leak detection fixture (10) and is sealed to the flange interface; the connector (8) is inserted into the connector flange (9) to be tested; the helium mass spectrometer leak detector (12) is connected to the inside of the flange integral leak detection fixture (10) by a vacuum bellows (11); the passive standard leak hole (4) is connected to the inside of the flange integral leak detection fixture (10) by a shut-off valve (5); The spray gun (3) is connected to the helium cylinder (1) by the pressure reducing valve (2), and the nozzle of the spray gun is set to face the connector (8).

2. The connector flange leak rate rapid detection device according to claim 1, characterized in that, A flange sealing ring (6) is provided between the flange interface and the connector flange (9) of the flange integral leak detection tool (10).

3. The rapid leak detection device for connector flanges according to claim 2, characterized in that, The connector (8) is covered with an isolation helium cover (7) that is sealed to the upper surface of the connector flange (9).

4. The connector flange leak rate rapid detection device according to claim 3, characterized in that, The isolation helium shield (7) includes a sealing cover plate (13), a sealing ring (14), a stainless steel shield body (15), and a rubber sealing gasket (16); the stainless steel shield body (15) is tubular and sleeved on the outside of the connector (8); the stainless steel shield body (15) and the upper surface of the connector flange (9) are sealed and connected by the rubber sealing gasket (16); the sealing cover plate (13) is set at the top of the stainless steel shield body (15), and the sealing cover plate (13) and the stainless steel shield body (15) are sealed and connected by the sealing ring (14).

5. The rapid leak detection device for connector flanges according to claim 4, characterized in that, The passive standard leak hole (4) should be selected with a leakage rate that is less than 25% different from the leakage rate index of the connector flange (9) to be tested.

6. The rapid leak detection device for connector flanges according to claim 5, characterized in that, The flange sealing ring (6) is a fluororubber sealing ring with a Shore hardness of 75.

7. A method for detecting leakage rate of a connector flange using a rapid leak detection device, employing the rapid leak detection device for connector flanges according to any one of claims 1-6, characterized in that the steps include... include: Step S1: Wipe the flange (9) of the connector to be tested clean with anhydrous ethanol and let it stand for 30 minutes. Check the connector (8) for obvious defects and looseness, and check whether there are scratches on the flange sealing surface. Step S2: Power on the helium mass spectrometer leak detector (12), warm it up for 30 minutes in standby mode, and connect the helium mass spectrometer leak detector (12) to the flange integral leak detection fixture (10) through the vacuum bellows (11); Step S3: Connect the passive standard leak hole (4) to the flange integral leak detection fixture (10) through the shut-off valve (5), with the shut-off valve (5) in the closed state; Step S4: Place the flange (9) to be tested on the test port of the flange overall leak detection fixture (10) and seal the flange sealing ring (6) by its own weight; Step S5: Start the helium mass spectrometer leak detector (12) in vacuum mode, and record the background value I0 after the value of the helium mass spectrometer leak detector (12) stabilizes. Step S6: Open the shut-off valve (5), use the spray gun (3) to spray helium into the passive standard leak hole (4), and record the calibration value I1 after the value of the helium mass spectrometer leak detector (12) stabilizes. Step S7: Close the shut-off valve (5), wait for the value of the helium mass spectrometer leak detector (12) to drop to the background value, and then use the spray gun (3) to spray helium into all the connectors (8) of the connector flange (9), and record the value of the helium mass spectrometer leak detector (12) as I2. Step S8: Process and interpret the overall leakage rate data of the connector flange (9). If the overall leakage rate Q of the connector flange (9) meets the index requirements, the test ends; if the overall leakage rate of the connector flange (9) does not meet the index requirements, proceed to the next step. Step S9: Preliminary quick location of leaking connectors (8): Use a spray gun (3) to spray helium onto each connector (8) of the connector flange (9) one by one. Observe and record the numbers of connectors (8) near the spray gun (3) when the value of the helium mass spectrometer (12) increases significantly. Use an isolation helium cover (7) to cover and seal the suspected connectors (8). Use the spray gun (3) to spray helium onto the remaining connectors (8) again until the value of the helium mass spectrometer (12) does not increase significantly. Step S10: After waiting for the value of the helium mass spectrometer leak detector (12) to drop to the background value, helium gas is sprayed into the isolation helium hood (7), and the value of the helium mass spectrometer leak detector (12) is recorded as I3.

8. The detection method of the connector flange leakage rate rapid detection device according to claim 7, characterized in that, In step S9: The spray gun (3) sprays helium for 2 seconds on each connector (8), with an interval of 5 seconds in between.

9. The detection method of the connector flange leakage rate rapid detection device according to claim 7, characterized in that, In step S9: The suspected connector (8) is covered and sealed with an isolation helium shield (7), and the remaining connectors (8) are sprayed with helium.

10. The detection method of the connector flange leakage rate rapid detection device according to claim 7, characterized in that, The formula for calculating the overall leakage rate Q of the connector flange (9) is as follows: Where Q0 represents the leakage rate value of the passive standard leak (4); The formula for calculating the leakage rate of a single connector (8) is as follows: Among them, Q x The value represents the leakage rate of a single connector (8), x = 1, 2, 3...n, where n is the total number of connectors (8).

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