An air tightness detection device in a connector production process and a control method thereof

Abstract

The application discloses an air tightness detection device in a connector production process and a control method thereof, and aims to provide an air tightness detection device in a connector production process and a control method thereof, which can detect the air tightness performance in multiple dimensions in the connector production process, guarantee product quality, reduce the scrap rate in the product final inspection process, and have the effects of improving product quality and reducing cost. The technical scheme points of the application are as follows: a connector body is composed of a plug connector and a socket connector; air tightness detection tools for detecting the air tightness of the connector are arranged at the two ends of the connector body; the air tightness detection tools comprise an air tightness tool air cylinder connecting end matched with the plug connector, a socket air tightness cabin matched with the socket connector, and a sealing screw arranged at one end of the socket air tightness cabin. The application is suitable for the technical field of connector air tightness detection.

Description

Technical Field

[0001] This invention relates to the field of connector airtightness testing technology, and more specifically, to an airtightness testing device and its control method in the connector manufacturing process. Background Technology

[0002] With the continuous deepening of deep-water and ocean research, underwater connectors are becoming increasingly important. Currently, domestic manufacturers usually use watertight testing to test the sealing performance of their products. This method is expensive in terms of labor, time, and equipment. Once a leak occurs, it may cause the product to be scrapped. By conducting airtight testing during the production process, the sealing performance can be tested, which greatly reduces sunk costs. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide an airtightness testing device and its control method in the connector production process, which can perform multi-dimensional airtightness performance testing during the connector production process, ensure product quality, reduce the scrap rate in the final inspection process, and improve product quality and reduce costs.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an airtightness testing fixture in the connector manufacturing process, comprising a connector body composed of a plug connector and a socket connector, wherein the connector body is provided with airtightness testing fixtures at both ends for testing the sealing performance of the connector, the airtightness testing fixture comprising an airtightness fixture gas cylinder connection end adapted to the plug connector, a socket airtightness chamber adapted to the socket connector, and a sealing screw disposed at one end of the socket airtightness chamber, wherein the sealing screw is used to seal the socket airtightness chamber and then ventilate the connector body, and a gas spectrum analyzer is used to detect the leakage rate at each sealing point.

[0005] The present invention is further configured such that the length of the socket airtight chamber is 1 / 2 to 2 / 3 of the length of the socket connection portion.

[0006] The present invention is further configured such that: the sealing end of the sealing screw is equipped with an elastic sealing gasket, and the elastic sealing gasket is adapted to the inner wall of the port of the socket airtight compartment to enhance the sealing airtightness.

[0007] The present invention is further configured such that the connecting thread specifications of the gas cylinder connection end of the airtight tool and the sealing screw are the same, and the two can be interchanged in the corresponding installation position to achieve reverse detection.

[0008] This application also provides a control method for an airtightness testing device during connector manufacturing, comprising the following steps:

[0009] S1. Preparation and Mode Selection: Install the socket airtight chamber onto the matching socket connector, seal the socket airtight chamber with sealing screws, and select helium testing or connecting a nitrogen cylinder for pressure holding performance testing and water tank bubble experiment according to the airtightness requirements:

[0010] S11. High-requirement airtightness performance testing: The helium inlet pressure for helium testing is controlled within the range of 0.1MPa-0.5MPa. Connect the helium cylinder hose to the airtight tool cylinder connection end, fill with helium, and use a gas spectrum analyzer to analyze the composition change curve of the leaking gas in real time. By comparing the leakage rate with historical fault data models, the system can preliminarily determine whether the leak point is located in a specific location such as a sealing ring, interface, or cable outlet.

[0011] 1. If the leakage rate fluctuates randomly at an extremely low level, the product is deemed qualified.

[0012] 2. The leakage rate gradually increases until it reaches a stable plateau, indicating the existence of a small but stable leakage path:

[0013] Further increase the inflation pressure gradually, in increments of 0.05 MPa, within a range of 0.1 MPa to 0.5 MPa, and record the leakage rate at each pressure. If the leakage rate increases approximately linearly with the pressure, the goodness of fit R is [value missing]. 2 When the value is ≥0.95, it is determined to be an interface micro-gap; if the leakage rate increases abruptly after a certain pressure threshold, and the increase is >30%, it is determined to be sealing ring aging.

[0014] 3. If the leakage rate quickly reaches its peak and then remains stable, it indicates the presence of gaps or contamination at the mating interface. It is recommended to clean the contact surfaces and check the mating dimensions for further investigation.

[0015] a. Use a lint-free cloth soaked in anhydrous ethanol to repeatedly wipe the sealing contact ring of the mating interface to remove any oil, metal shavings, dust and other contaminants that may be attached. After wiping, let it stand for 5-10 minutes to allow the interface to dry.

[0016] b. Refill with air at the original test pressure and monitor the change in leakage rate; if the leakage rate decreases by ≥60% after retesting and the stable value is within the qualified threshold, it is determined to be interface contamination; if the leakage rate decreases by <20%, or remains at a high stable value after the decrease, it is preliminarily determined that there is a gap at the interface.

[0017] c. Use a micrometer or plug gauge to measure the actual dimensions of the mating interface, such as the outer diameter of the socket connector and the inner diameter of the socket airtight compartment, and compare them with the dimensional tolerances of the design drawings; if the dimensional deviation exceeds the design allowable range of ±0.02mm, it is diagnosed as a mating interface gap; if the dimensions meet the requirements, further check whether there are hidden scratches or dents on the interface.

[0018] 4. If the leakage rate continues to increase linearly without a stable trend, it is determined to be a structural defect in the tail sealing area, and the potting process needs to be checked in detail.

[0019] S12. Low-requirement airtightness performance test: The pressure holding time for the pressure holding performance test shall not be less than 30 minutes, and the pressure holding pressure shall be 0.2MPa-0.4MPa. Connect a nitrogen cylinder, fill it with nitrogen, and use a pressure sensor to monitor pressure changes to judge the pressure holding performance. Immerse the connector in a water tank to observe the bubble situation, and record and analyze the pressure-time curve of the entire pressure holding process in real time.

[0020] 1. The curve shows a slight drop caused by temperature equilibrium and system elastic deformation, then quickly stabilizes and passes the test within 15-20 minutes, indicating a qualified product.

[0021] 2. The continuous and uniform linear downward trend of the curve indicates the existence of a small but stable leakage path, which is due to aging of the sealing ring or micro-gaps at the interface.

[0022] 3. If the curve drops sharply and then decays slowly, it is determined that there is a significant leak due to structural defects or improper installation.

[0023] S2. Overall airtightness test of connector: When the connector head is not longitudinally sealed, test the overall airtightness in one test according to the above sealing and inflation steps.

[0024] S3. Reverse test: Taking advantage of the fact that the gas cylinder connection end of the airtight tooling has the same thread as the sealing screw connection of the airtight tooling, the reverse test is performed by direct replacement.

[0025] S4. Single component airtightness test: Use the corresponding sealing end cap to seal the end face, install the airtight tooling gas cylinder connection end part at the plug tail or socket airtight chamber interface, and repeat the corresponding airtightness test steps.

[0026] The present invention is further configured such that, in step S12, during the later stage of pressure holding (25-30 minutes), a sudden drop in the pressure curve occurs:

[0027] 1. If the pressure curve suddenly drops slightly and then stabilizes, it is determined that the sealing structure has become elastically relaxed due to prolonged pressure. It is necessary to adjust the compression of the seal or replace it with a seal made of a high-elasticity material.

[0028] 2. If the pressure curve suddenly shows a significant and rapid drop, and the drop exceeds 10% of the initial holding pressure, without any subsequent stabilization trend, it is determined that the contact area between the seal and the installation interface has partially peeled off due to long-term pressure load, or the temporary seal of the tooling thread connection has failed. It is recommended to re-check the pre-tightening force of the seal and the tightening torque of the tooling connection.

[0029] The beneficial effects of this invention are:

[0030] 1. The airtight fixture's gas cylinder connection end is matched with the plug connector, and the socket airtight chamber is matched with the socket connector, accurately simulating the sealing environment of the connector in actual use. During testing, after the sealing screws seal the socket airtight chamber, air is introduced into the connector body, and then a gas spectrometer is used to detect the leakage rate at each sealing point. This ensures that the test results accurately reflect the airtight performance of the connector, avoiding testing errors caused by mismatch between the testing fixture and the connector, and greatly improving the accuracy of the test.

[0031] 2. The length of the socket airtight chamber is set to 1 / 2 to 2 / 3 of the socket connector connection. This ensures effective enclosure of the connector connection and simulates an actual sealing environment while avoiding material waste and increased overall tooling volume due to an excessively long chamber. The appropriate length allows for more uniform gas distribution within the chamber during testing, more accurately reflecting the airtightness of the connector connection. The sealing screw's plugging end is equipped with an elastic sealing gasket, which fits the inner wall of the socket airtight chamber port, greatly enhancing the airtightness of the seal. During use, the elastic gasket fills the tiny gaps between the sealing screw and the inner wall of the chamber port, preventing gas leakage. Even with pressure fluctuations during use, the elastic gasket maintains a good seal through its elastic deformation. The gas cylinder connection end of the airtight tooling has the same thread specification as the sealing screw, allowing them to be interchanged at corresponding installation positions for reverse testing. This provides significant flexibility for testing, as some connectors may have issues that are difficult to detect with forward testing. Reverse testing allows for a comprehensive evaluation of the connector's airtightness from another perspective.

[0032] 3. The control method of the airtightness testing device in connector production has significant advantages. It can meet different airtightness requirements, accurately locate and differentiate leakage problems, and provides two testing modes: high-requirement and low-requirement. High-requirement testing uses helium gas testing for high-precision leak location; low-requirement testing uses nitrogen pressure holding and water tank bubble experiments, which are simple to operate and low-cost. During testing, changes in leakage rate can accurately determine the leak location. Furthermore, through cleaning, retesting, and measurement steps, the causes of failures can be further differentiated, providing direction for repair and improvement, and enhancing product quality and stability. It ensures the overall reliability of the product performance. It can perform overall airtightness testing and can also test from different directions through reverse testing, avoiding problems missed by forward testing. Airtightness testing of individual components can promptly identify defects in those components. In addition, the data accumulated during the testing process, compared with historical failure models, can help with continuous product design and process improvement, enhancing the company's market competitiveness.

[0033] 4. When the pressure curve suddenly drops slightly and then stabilizes, it indicates that the sealing structure has experienced elastic relaxation due to prolonged pressure. If the pressure curve drops significantly and rapidly, exceeding the initial holding pressure by more than 10% and showing no stabilizing trend, it indicates localized peeling between the seal and the mounting interface or temporary seal failure at the tooling threaded connection. This precise diagnosis avoids blindly troubleshooting, allowing maintenance personnel to quickly pinpoint the root cause of the fault, saving considerable time and effort and greatly improving maintenance efficiency. The method provides clear direction for subsequent improvements. For issues of elastic relaxation in the sealing structure, it guides adjustments to the seal compression or replacement with a seal made of a high-elasticity material. For issues of localized peeling between the seal and the tooling threaded connection, it recommends re-checking the seal preload and tooling tightening torque. Through these targeted improvement measures, problems discovered during airtightness testing can be effectively resolved, improving the sealing performance and overall quality of the connector, reducing product failures and defect rates caused by sealing issues, and enhancing the product's competitiveness in the market. Attached Figure Description

[0034] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0035] Figure 2 This is a cross-sectional view of the present invention;

[0036] Figure 3 A flowchart illustrating an embodiment of a control method for an airtightness testing device in a connector manufacturing process;

[0037] Figure 4 Analysis of the pressure holding curve for connector airtightness testing;

[0038] Figure 5 This is a dynamic leakage spectrum analysis diagram for connector airtightness testing;

[0039] Figure 1-5 Reference numerals: 1. Plug connector; 2. Socket connector; 3. Connector body; 4. Airtight tooling gas cylinder connection end; 5. Socket airtight chamber; 6. Sealing screw. Detailed Implementation

[0040] Reference Figure 1-5 The embodiments of the present invention will be further described below.

[0041] For ease of explanation, spatial relative terms such as “up,” “down,” “left,” and “right” are used in the embodiments to describe the relationship of one element or feature shown in the figures relative to another element or feature. It should be understood that, in addition to the orientations shown in the figures, spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figures is inverted, an element described as being “down” of other elements or features would be positioned “up” of those other elements or features. Therefore, the exemplary term “down” can encompass both up and down orientations. The device may be positioned in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0042] Moreover, relational terms such as “first” and “second” are used merely to distinguish one component from another that has the same name, without necessarily requiring or implying any such actual relationship or order between the components.

[0043] Figures 1 to 5 The diagram illustrates an airtightness testing fixture used in connector manufacturing. It includes a connector body 3 composed of a plug connector 1 and a socket connector 2. Both ends of the connector body 3 are equipped with airtightness testing fixtures for testing the connector's sealing performance. Each airtightness testing fixture includes an airtightness testing fixture gas cylinder connection end 4 adapted to the plug connector 1, a socket airtightness chamber 5 adapted to the socket connector 2, and a sealing screw 6 located at one end of the socket airtightness chamber 5. The airtightness testing fixture gas cylinder connection end 4 is adapted to the plug connector 1, and the socket airtightness chamber 5 is adapted to the socket connector 2, accurately simulating the sealing environment of the connector in actual use. During testing, after the sealing screw 6 seals the socket airtightness chamber 5, air is introduced into the connector body 3, and a gas spectrometer is used to detect the leakage rate at each sealing point. This ensures that the test results accurately reflect the airtightness performance of the connector, avoiding testing errors caused by mismatch between the testing fixture and the connector, and greatly improving the accuracy of the test. The entire testing process is simple and efficient, reducing testing time and labor costs. For connectors in mass production, it can significantly improve testing efficiency on the production line, accelerate product production, and improve the company's production efficiency.

[0044] When the length of the socket airtight chamber 5 is less than 1 / 2 of the socket connection part, the airtight chamber is too short and cannot provide sufficient buffer space and sealing path for the internal gas. When the connector is working, the gas is prone to leak from the gaps, resulting in a significant reduction in airtight performance. When the length of the socket airtight chamber 5 is greater than 2 / 3 of the socket connection part, the excessive length of the socket airtight chamber 5 will occupy too much space, causing difficulties in the overall layout. At the same time, the processing difficulty and time during production will also increase accordingly, increasing manufacturing costs. Therefore, the optimal length of the socket airtight chamber 5 is 1 / 2 to 2 / 3 of the socket connection part. The appropriate length allows for a more uniform distribution of gas within the socket airtight chamber 5 during testing, which can more accurately reflect the airtightness of the socket connector 2 connection part. It can also ensure effective enclosure of the socket connector 2 connection part and simulate the actual sealing environment while avoiding material waste and an increase in the overall size of the tooling due to an excessively long airtight chamber.

[0045] The sealing end of the sealing screw 6 is equipped with an elastic sealing gasket. The elastic sealing gasket is adapted to the inner wall of the port of the socket airtight chamber 5, which greatly enhances the airtightness of the seal. During use, the elastic sealing gasket can fill the tiny gap between the sealing screw 6 and the inner wall of the port of the socket airtight chamber 5 to prevent gas leakage. Even if there is a certain pressure fluctuation during use, the elastic sealing gasket can maintain a good sealing effect through its own elastic deformation.

[0046] The gas cylinder connection end 4 of the airtight tool and the sealing screw 6 have the same thread specification. They can be interchanged in the corresponding installation position to achieve reverse testing, which brings great flexibility to the testing work. In actual testing, some connectors may have problems that are difficult to detect by forward testing. By reverse testing, the airtight performance of the connector can be fully evaluated from another direction.

[0047] This application also provides a control method for an airtightness testing device during connector manufacturing, comprising the following steps:

[0048] S1. Preparation and Mode Selection: Install the socket airtight chamber 5 onto the matching socket connector 2, seal the socket airtight chamber 5 with the sealing screws 6, and select helium testing or connecting a nitrogen cylinder for pressure holding performance testing and water tank bubble experiment according to the airtightness requirements:

[0049] S11. High-requirement airtightness performance testing: The helium inlet pressure for helium testing is controlled within the range of 0.1MPa-0.5MPa. Connect the helium cylinder hose to the airtight tool cylinder connection end 4. After filling with helium, use a gas spectrum analyzer to analyze the composition change curve of the leaking gas in real time. By comparing the leakage rate with historical fault data models, the system can preliminarily determine whether the leak point is located in a specific location such as the sealing ring, interface, or cable outlet.

[0050] 1. If the leakage rate fluctuates randomly at an extremely low level, the product is deemed qualified.

[0051] 2. The leakage rate gradually increases until it reaches a stable plateau, indicating the existence of a small but stable leakage path:

[0052] Further increase the inflation pressure gradually, in increments of 0.05 MPa, within a range of 0.1 MPa to 0.5 MPa, and record the leakage rate at each pressure. If the leakage rate increases approximately linearly with the pressure, the goodness of fit R is [value missing]. 2 When the value is ≥0.95, it is determined to be an interface micro-gap; if the leakage rate increases abruptly after a certain pressure threshold, and the increase is >30%, it is determined to be sealing ring aging.

[0053] 3. If the leakage rate quickly reaches its peak and then remains stable, it indicates the presence of gaps or contamination at the mating interface. It is recommended to clean the contact surfaces and check the mating dimensions for further investigation.

[0054] a. Use a lint-free cloth soaked in anhydrous ethanol to repeatedly wipe the sealing contact ring of the mating interface to remove any oil, metal shavings, dust and other contaminants that may be attached. After wiping, let it stand for 5-10 minutes to allow the interface to dry.

[0055] b. Refill with air at the original test pressure and monitor the change in leakage rate; if the leakage rate decreases by ≥60% after retesting and the stable value is within the qualified threshold, it is determined to be interface contamination; if the leakage rate decreases by <20%, or remains at a high stable value after the decrease, it is preliminarily determined that there is a gap at the interface.

[0056] c. Use a micrometer or plug gauge to measure the actual dimensions of the mating interface, such as the outer diameter of the socket connector 2 and the inner diameter of the socket airtight chamber 5, and compare them with the dimensional tolerances of the design drawings; if the dimensional deviation exceeds the design allowable range of ±0.02mm, it is diagnosed as a mating interface gap; if the dimensions meet the requirements, further check whether there are hidden scratches or dents on the interface.

[0057] 4. If the leakage rate continues to increase linearly without a stable trend, it is determined to be a structural defect in the tail sealing area, and the potting process needs to be checked in detail.

[0058] S12. Low-requirement airtightness performance test: The pressure holding time for the pressure holding performance test shall not be less than 30 minutes, and the pressure holding pressure shall be 0.2MPa-0.4MPa. Connect a nitrogen cylinder, fill it with nitrogen, and use a pressure sensor to monitor pressure changes to judge the pressure holding performance. Immerse the connector in a water tank to observe the bubble situation, and record and analyze the pressure-time curve of the entire pressure holding process in real time.

[0059] 1. The curve shows a slight drop caused by temperature equilibrium and system elastic deformation, then quickly stabilizes and passes the test within 15-20 minutes, indicating a qualified product.

[0060] 2. The continuous and uniform linear downward trend of the curve indicates the existence of a small but stable leakage path, which is due to aging of the sealing ring or micro-gaps at the interface.

[0061] 3. If the curve drops sharply and then decays slowly, it is determined that there is a significant leak due to structural defects or improper installation.

[0062] S2. Overall airtightness test of connector: When the connector head is not longitudinally sealed, test the overall airtightness in one test according to the above sealing and inflation steps.

[0063] S3. Reverse test: Taking advantage of the fact that the gas cylinder connection end 4 of the airtight tooling has the same connection thread as the sealing screw 6 of the airtight tooling, directly replace and perform a reverse test.

[0064] S4. Single component airtightness test: Use the corresponding sealing end cap to seal the end face, install the airtight tooling gas cylinder connection end 4 part at the plug tail or socket airtight chamber 5 interface, and repeat the corresponding airtightness test steps.

[0065] The control method of the airtightness testing device in connector production offers significant advantages, meeting diverse airtightness requirements and accurately locating and differentiating leakage problems. It provides two testing modes: high-requirement and low-requirement. High-requirement testing uses helium gas for precise leak location, while low-requirement testing employs nitrogen pressure holding and water tank bubble experiments, offering simple operation and low cost. During testing, changes in leakage rate accurately determine the leak location. Furthermore, steps such as cleaning, retesting, and measurement can further differentiate the causes of faults, providing direction for repair and improvement, and enhancing product quality and stability. It ensures overall product performance reliability by performing comprehensive airtightness testing and also enabling reverse testing from different directions to avoid missing problems during forward testing. Airtightness testing of individual components can promptly identify defects in those components. Moreover, data accumulated during the testing process, compared with historical fault models, supports continuous improvement in product design and processes, enhancing the company's market competitiveness.

[0066] The present invention is further configured such that, in step S12, during the later stage of pressure holding (25-30 minutes), a sudden drop in the pressure curve occurs:

[0067] 1. If the pressure curve suddenly drops slightly and then stabilizes, it is determined that the sealing structure has become elastically relaxed due to prolonged pressure. It is necessary to adjust the compression of the seal or replace it with a seal made of a high-elasticity material.

[0068] 2. If the pressure curve suddenly shows a significant and rapid drop, and the drop exceeds 10% of the initial holding pressure, without any subsequent stabilization trend, it is determined that the contact area between the seal and the installation interface has partially peeled off due to long-term pressure load, or the temporary seal of the tooling thread connection has failed. It is recommended to re-check the pre-tightening force of the seal and the tightening torque of the tooling connection.

[0069] When the pressure curve suddenly drops slightly and then stabilizes, it indicates that the sealing structure has experienced elastic relaxation due to prolonged pressure. If the pressure curve drops significantly and rapidly, exceeding the initial holding pressure by more than 10% and showing no stabilizing trend, it indicates localized peeling between the seal and the mounting interface or temporary seal failure at the tooling threaded connection. This precise diagnosis avoids blindly troubleshooting, allowing maintenance personnel to quickly pinpoint the root cause of the fault, saving considerable time and effort and greatly improving maintenance efficiency. The method provides clear direction for subsequent improvements. For issues of elastic relaxation in the sealing structure, it guides adjustments to the seal compression or replacement with a seal made of a high-elasticity material. For issues of localized peeling between the seal and the mounting interface or tooling threaded connection, it recommends re-checking the seal preload and tooling tightening torque. Through these targeted improvement measures, problems discovered during airtightness testing can be effectively resolved, improving the sealing performance and overall quality of the connector, reducing product failures and defect rates due to sealing issues, and enhancing the product's competitiveness in the market.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Those skilled in the art...

[0071] All ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of this invention should include

[0072] Within the scope of protection of this invention.

Claims

1. An airtightness testing device in the connector manufacturing process, comprising a connector body (3) consisting of a plug connector (1) and a socket connector (2), characterized in that, The connector body (3) is provided with airtight testing fixtures at both ends for testing the sealing performance of the connector. The airtight testing fixtures include an airtight fixture gas cylinder connection end (4) adapted to the plug connector (1), a socket airtight chamber (5) adapted to the socket connector (2), and a sealing screw (6) set at one end of the socket airtight chamber (5). After the sealing screw (6) is used to seal the socket airtight chamber (5), the connector body (3) is vented, and the leakage rate of each sealing point is detected by a gas spectrum analyzer. The gas cylinder connection end (4) of the airtight tool has the same thread specification as the sealing screw (6), and the two can be interchanged in the corresponding installation position to achieve reverse detection.

2. The airtightness testing device in the connector manufacturing process according to claim 1, characterized in that, The length of the socket airtight chamber (5) is 1 / 2 to 2 / 3 of the length of the socket connection part.

3. The airtightness testing device in the connector manufacturing process according to claim 1, characterized in that, The sealing screw (6) is fitted with an elastic sealing gasket at its sealing end. The elastic sealing gasket is adapted to the inner wall of the port of the socket airtight compartment (5) to enhance the sealing airtightness.

4. A control method for an airtightness detection device in a connector manufacturing process according to any one of claims 1-3, characterized in that, Includes the following steps: S1. Preparation and Mode Selection: Install the socket airtight chamber (5) onto the matching socket connector (2), seal the socket airtight chamber (5) with sealing screws (6), and select helium testing or connecting a nitrogen cylinder for pressure holding performance testing and water tank bubble experiment according to the airtightness requirements: S11. High-requirement airtightness performance testing: The helium gas inlet pressure for helium testing is controlled within the range of 0.1MPa-0.5MPa. Connect the helium gas cylinder hose to the airtight tool cylinder connection end (4). After filling with helium, use a gas spectrum analyzer to analyze the composition change curve of the leaking gas in real time. By comparing the leakage rate with historical fault data models, the system can preliminarily determine the location of the leak point, including the sealing ring, interface, or cable outlet.

1. If the leakage rate fluctuates randomly at an extremely low level, the product is deemed qualified.

2. The leakage rate gradually increases until it reaches a stable plateau, indicating the existence of a small but stable leakage path: Further increase the inflation pressure gradually, in increments of 0.05 MPa, within a range of 0.1 MPa to 0.5 MPa, and record the leakage rate at each pressure. If the leakage rate increases approximately linearly with the pressure, the goodness of fit R is [value missing]. 2 When the value is ≥0.95, it is determined to be an interface micro-gap; if the leakage rate increases abruptly after a certain pressure threshold, and the increase is >30%, it is determined to be sealing ring aging.

3. If the leakage rate quickly reaches its peak and then remains stable, it indicates the presence of gaps or contamination at the mating interface. It is recommended to clean the contact surfaces and check the mating dimensions for further investigation. a. Use a lint-free cloth soaked in anhydrous ethanol to repeatedly wipe the mating interface and seal the contact ring to remove any contaminants that may be attached, including oil, metal shavings or dust. After wiping, let it stand for 5-10 minutes to allow the interface to dry. b. Refill with air at the original test pressure and monitor the change in leakage rate; if the leakage rate decreases by ≥60% after retesting and the stable value is within the qualified threshold, it is determined to be interface contamination; if the leakage rate decreases by <20%, or remains at a high stable value after the decrease, it is preliminarily determined that there is a gap at the interface. c. Use a micrometer or plug gauge to measure the actual dimensions of the mating interface, such as the outer diameter of the socket connector (2) and the inner diameter of the socket airtight chamber (5), and compare them with the dimensional tolerances of the design drawings; if the dimensional deviation exceeds the design allowable range of ±0.02mm, it is diagnosed as a mating interface gap; if the dimensions meet the requirements, further check whether there are hidden scratches or dents on the interface.

4. If the leakage rate continues to increase linearly without a stable trend, it is determined to be a structural defect in the tail sealing area, and the potting process needs to be checked in detail. S12. Low-requirement airtightness performance test: The pressure holding time for the pressure holding performance test shall not be less than 30 minutes, and the pressure holding pressure shall be 0.2MPa-0.4MPa. Connect a nitrogen cylinder, fill it with nitrogen, and use a pressure sensor to monitor pressure changes to judge the pressure holding performance. Immerse the connector in a water tank to observe the bubble situation, and record and analyze the pressure-time curve of the entire pressure holding process in real time.

1. The curve shows a slight drop caused by temperature equilibrium and system elastic deformation, then quickly stabilizes and passes the test within 15-20 minutes, indicating a qualified product.

2. The continuous and uniform linear downward trend of the curve indicates the existence of a small but stable leakage path, which is due to aging of the sealing ring or micro-gaps at the interface.

3. If the curve drops sharply and then decays slowly, it is determined that there is a significant leak due to structural defects or improper installation. S2. Overall airtightness test of connector: When the connector head is not longitudinally sealed, test the overall airtightness in one test according to the above sealing and inflation steps. S3. Reverse test: Taking advantage of the fact that the gas cylinder connection end (4) of the airtight tooling has the same connection thread as the sealing screw (6) of the airtight tooling, the reverse test is carried out by direct replacement. S4. Single component airtightness test: Use the corresponding sealing end cap to seal the end face, install the airtight tool gas cylinder connection end (4) part at the plug tail or socket airtight chamber (5) interface, and repeat the corresponding airtightness test steps.

5. The control method for an airtightness detection device in the connector manufacturing process according to claim 4, characterized in that, In step S12, during the later stage of pressure holding (25-30 minutes), a sudden drop in the pressure curve occurs:

1. If the pressure curve suddenly drops slightly and then stabilizes, it is determined that the sealing structure has become elastically relaxed due to prolonged pressure. It is necessary to adjust the compression of the seal or replace it with a seal made of a high-elasticity material.

2. If the pressure curve suddenly shows a significant and rapid drop, and the drop exceeds 10% of the initial holding pressure, without any subsequent stabilization trend, it is determined that the contact area between the seal and the installation interface has partially peeled off due to long-term pressure load, or the temporary seal of the tooling thread connection has failed. It is recommended to re-check the pre-tightening force of the seal and the tightening torque of the tooling connection.

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