CN116858450A - A gas cylinder pressure maintaining leak testing device and pressure maintaining leak testing method - Google Patents

Abstract

The invention relates to a pressure maintaining leakage testing device and a pressure maintaining leakage testing method for a gas cylinder; comprises a vacuum bin body, wherein a pressure maintaining pipeline is arranged in the vacuum bin body; the vacuum bin body is provided with a vacuumizing device, a vacuum bin detection unit and a helium filling pipeline part; the pressure maintaining pipeline is provided with a plurality of gas cylinder connectors and pipeline pressure sensors, a pressure maintaining pipeline detection unit is arranged outside the vacuum bin body, and the pressure maintaining pipeline is also connected with a non-helium inert gas filling pipeline part; the vacuum bin detection unit comprises a bin body pressure sensor and an oxygen content meter; the pressure maintaining pipeline detection unit comprises a pipeline vacuumizing device and a gas detection part; the gas cylinder can be prevented from being corroded to cause gas pollution in a pressure and/or gas component detection and analysis mode, meanwhile, the operation difficulty of detection personnel can be reduced, the misjudgment risk is reduced, and the gas cylinder gas tightness detection device has the characteristics of high detection accuracy and capability of detecting the gas tightness of the gas cylinder.

Description

A gas cylinder pressure maintaining leak testing device and pressure maintaining leak testing method

Technical field

The invention relates to the technical field of gas cylinder detection, specifically a gas cylinder pressure maintaining leak testing device and a pressure maintaining leak testing method.

Background technique

Existing gas cylinder leak testing mainly relies on manual use of leak testing liquid for leak testing. This leak testing method is relatively traditional and has the following defects: 1. When using leak testing liquid for leak testing, when the gas cylinder leaks significantly The effect is obvious, and it cannot be detected when a small amount of leakage occurs. This situation causes the problem of large leakage of product gas in the cylinder when it is transported over a long distance after being filled, which not only causes huge losses to the unit using the cylinder. At the same time, when cylinder gas is prohibited to be discharged, it will cause environmental pollution problems; 2. When a large number of gas cylinders need to be tested, the leak test liquid is relatively expensive, and the leak test liquid itself may cause corrosion and corrosion to the cylinders. The risk of gas contamination; the above situation has caused high detection costs, affected the service life of gas cylinders, and caused the product gas to be substandard; especially when the gas cylinders are filled with electronic-grade and high-purity gases, it will cause Defects in which the product is contaminated and cannot be used; 3. During the leak test process, there are professional requirements for leak test personnel, especially defects in the leak test judgment that are affected by personnel skills, environment and other factors, resulting in inconsistent results and large errors.

Contents of the invention

The object of the present invention is to provide a gas cylinder pressure maintaining leak testing device and a pressure maintaining leak testing method to solve the problems raised in the above background technology.

In order to achieve the above objects, the present invention provides the following technical solutions:

A pressure-maintaining and leak-testing device for gas cylinders, including a vacuum warehouse body, the vacuum warehouse body is provided with a pressure-maintaining pipeline; the vacuum warehouse body is provided with a vacuum pumping device, a vacuum warehouse detection unit and a helium filling pipeline part; the pressure-maintaining pipeline is provided with several gas bottle joints and pipeline pressure sensors, the outside of the vacuum warehouse body is provided with a pressure-maintaining pipeline detection unit, and the pressure-maintaining pipeline is also connected to the non-helium inert gas filling pipeline part; so The vacuum chamber detection unit includes a chamber pressure sensor for detecting the internal pressure of the vacuum chamber body, and an oxygen content meter for detecting the oxygen content inside the vacuum chamber body; the pressure maintaining pipeline detection unit at least includes a It is a pipeline vacuuming device used to evacuate pressure-maintaining pipelines, and a gas detection part used to detect whether other gases leak into pressure-maintaining pipelines.

Beneficial effects of the present invention: The present invention uses the vacuum warehouse body installed with the pressure-maintaining pipeline as a container, and makes the pressure-maintaining pipeline another container. Through the gas bottle and the pressure-maintaining pipeline, the gas bottle and the pressure-maintaining pipeline are placed in the vacuum warehouse. In vivo, and through pressure detection and/or gas component detection and analysis, the leakage and air tightness of the gas cylinder are detected. It should be noted that the leakage of the gas cylinder described in the present invention refers to the damage to the bottle valve. If a large leakage occurs, the air tightness of the gas cylinder is mainly due to trace leakage. After research, it is found that the trace leakage mainly comes from the thread of the bottle valve; further, the present invention can realize batch detection of gas cylinders by setting up several gas cylinder joints. In order to achieve the purpose of improving detection efficiency and reducing detection costs; through pressure and/or gas component detection and analysis, the phenomenon of gas pollution caused by corrosion of gas bottles can be avoided, and at the same time, it can reduce the operational difficulty of the detection personnel and reduce the risk of misjudgment. It has It has the characteristics of high detection accuracy and the ability to detect the air tightness of gas bottles.

Preferably, the helium filling pipeline part includes a helium bottle or a helium pipe network, the helium bottle or helium pipe network is connected to the vacuum chamber body through a pipe, and the pipe is provided with a first pneumatic valve and a helium pressure sensor.

Preferably, the non-helium inert gas filling pipeline section includes an inert gas bottle or an inert gas pipeline network, the inert gas bottle or the inert gas pipeline network is connected to a pressure maintaining pipeline through a pipeline, and a second pneumatic valve and an inert gas pressure are provided on the pipeline. sensor.

Preferably, the vacuum warehouse body is provided with a door with an electronically controlled lock, and the vacuum warehouse body is provided with a ventilation pipeline with a ventilation motor.

Preferably, the pressure-maintaining pipeline is connected to the pipeline vacuuming device through a vacuuming pipeline, and the vacuuming pipeline is sequentially provided with a first tee, a second tee, a vacuum gauge for detecting the vacuum degree in the vacuuming pipeline, and a third pneumatic Valve; the gas detection part includes a pump-type alarm connected to the third end of the first tee, and a helium mass spectrometer leak detector connected to the third end of the second tee.

Preferably, a fourth pneumatic valve is provided between the third end of the first three-way and the pump-type alarm; and a fifth pneumatic valve is provided between the third end of the second three-way and the helium mass spectrometer leak detector.

The invention also includes a PLC control system. The signal input terminals of the PLC control system are respectively connected with the pipeline pressure sensor, pipeline temperature sensor, warehouse pressure sensor, oxygen content meter, helium pressure sensor, inert gas pressure sensor, vacuum gauge, and pump suction type. Alarm instrument and helium mass spectrometer leak detector; the signal output end of the PLC control system is respectively connected with the first pneumatic valve, the second pneumatic valve, the third pneumatic valve, the fourth pneumatic valve, the fifth pneumatic valve, the vacuum device, the vacuum gauge and Pipe vacuuming device; the pressure-maintaining pipeline is also provided with a pipeline temperature sensor.

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a positive pressure air tightness test of a bottle valve interface, a negative pressure air tightness test of a bottle valve interface, an alarm detection test, and a helium mass spectrometer Leak detector detection test; the bottle valve interface positive pressure air tightness test is used to detect whether the gas in the pressure maintaining pipeline leaks into the vacuum warehouse through the bottle valve and whether the gas in the cylinder enters the pressure maintaining pipeline; the bottle valve The interface negative pressure air tightness test is used to detect whether there is gas in the gas cylinder or vacuum chamber body entering the pressure maintaining pipeline through the bottle valve interface; the alarm detection test is used to detect whether there is gas in the gas cylinder passing through the bottle valve interface into the pressure-maintaining pipeline; the helium mass spectrometer leak detector detection test is used to detect whether the gas in the vacuum chamber body leaks into the pressure-maintaining pipeline through the bottle valve.

The beneficial effects of the present invention are: the above-mentioned methods in the present invention can be used cross-wise to improve the accuracy of the pressure-maintaining leak test of gas bottles. All the above-mentioned four methods can be used, or at least one of them can be selected for use; specifically, this method The positive pressure air tightness test of the bottle valve interface described in the invention is used to detect whether the bottle valve leaks and the air tightness, and the negative pressure air tightness test of the bottle valve interface is used to detect whether the bottle valve leaks and the air tightness. The alarm instrument detection test is mainly used to detect whether the bottle valve is leaking, and the helium mass spectrometer leak detector detection test is mainly used to detect the air tightness of the bottle valve; the present invention can be used for batch operations to detect gas bottles. When there is no problem in a batch When there is a problem, the entire batch can be judged to be qualified; when there is a problem in a batch, the batch can be split and tested separately to determine the specific bottle valve with the problem. The above method can effectively improve detection efficiency while ensuring detection accuracy.

Preferably, the positive pressure air tightness test of the bottle valve interface, the negative pressure air tightness test of the bottle valve interface, the alarm detection test and the helium mass spectrometer leak detector detection test respectively include the following steps:

The positive pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder joint in the pressure-maintaining pipeline;

Step 2: Fill the test gas into the pressure-maintaining pipeline so that the gas pressure in the pressure-maintaining pipeline is greater than the pressure in the vacuum chamber body and less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor to detect whether the gas pressure in the pressure-maintaining pipeline fluctuates. When the pipeline pressure sensor detects that the gas pressure in the pressure-maintaining pipeline drops, it proves that the gas in the pressure-maintaining pipeline leaks to the vacuum chamber body through the bottle valve. medium, that is, the air tightness of the bottle valve is poor; when the pipeline pressure sensor detects an increase in gas pressure in the pressure-maintaining pipeline, it proves that the gas in the cylinder enters the pressure-maintaining pipeline, that is, the bottle valve leaks; when the pipeline pressure sensor detects When the gas in the pressure-maintaining pipeline does not change, it proves that the air tightness of the bottle valve is good and no leakage will occur;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline, or use the pipeline vacuum device to evacuate;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder joint in the pressure-maintaining pipeline;

Step 2: Open the second pneumatic valve, and the non-helium inert gas in the inert gas bottle or inert gas pipe network enters the pressure-maintaining pipeline for gas replacement. After replacement, close the second pneumatic valve and relieve the pressure. Finally, use the pipeline vacuum device to The pressure-maintaining pipeline is evacuated, and the vacuum degree in the pressure-maintaining pipeline is determined through a vacuum gauge;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body, and the pressure in the vacuum chamber body is greater than the pressure in the pressure maintaining pipeline; the cylinder valve of the gas cylinder is in a closed state;

Step 4: Use the pipeline pressure sensor to detect whether the gas pressure in the pressure-maintaining pipeline rises. When the pipeline pressure sensor detects that the gas pressure in the pressure-maintaining pipeline rises, it proves that the gas in the vacuum chamber or cylinder enters the pressure-maintaining pipeline, that is, The bottle valve is leaking or has poor air tightness;

When the pipeline pressure sensor detects that the gas pressure in the pressure-maintaining pipeline remains unchanged, the air tightness of the bottle valve is good and leakage will not occur;

The alarm detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder joint in the pressure-maintaining pipeline;

Step 2: Open the second pneumatic valve, and the non-helium inert gas in the inert gas bottle or inert gas pipe network enters the pressure-maintaining pipeline for gas replacement. After replacement, close the second pneumatic valve and release the pressure to reduce the pressure in the pressure-maintaining pipeline. Keep consistent with the pressure in the vacuum chamber body;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body;

Step 4: The PLC control system controls the fourth pneumatic valve to open and starts the pump-type alarm; in step 1, the gas in the cylinder is consistent with the gas detected by the pump-type alarm;

Step 5: When the pump-type alarm detects the gas in the pressure-maintaining pipeline, it detects that the gas in the pressure-maintaining pipeline contains the components of the gas in the cylinder, indicating that the bottle valve is leaking;

Detect that the gas in the pressure-maintaining pipeline does not contain the components of the gas in the cylinder, indicating that there is no leakage in the cylinder valve;

The helium mass spectrometer leak detector detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder joint in the pressure-maintaining pipeline;

Step 2: Start the vacuuming device and evacuate the vacuum chamber body. When the preset vacuum value is reached, close the vacuuming device and open the first pneumatic valve to allow helium gas in the helium bottle or helium pipe network to enter. In the vacuum chamber body;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body is greater than the pressure in the pressure-maintaining pipe, and the pressure in the vacuum chamber body is less than the pressure in the gas cylinder;

Step 4: The PLC control system controls the fifth pneumatic valve to open and starts the helium mass spectrometer leak detector;

Step 5: When the helium mass spectrometer leak detector detects the gas in the pressure-maintaining pipeline, it detects that the gas in the pressure-maintaining pipeline contains helium, indicating that the bottle valve has poor air tightness;

It is detected that the gas in the pressure-maintaining pipeline does not contain helium, indicating that the air tightness of the bottle valve is good.

Preferably, after the test is completed, when personnel need to enter, the ventilation motor is turned on, and the oxygen content meter detects the oxygen content in the vacuum chamber body in real time. When the oxygen content reaches the human body entry standard, the chamber door with an electrically controlled lock is opened. .

A gas bottle pressure-maintaining leak test device and a pressure-maintaining leak test method made according to the above solution. The present invention uses the vacuum warehouse body installed with the pressure-maintaining pipeline as a container, so that the pressure-maintaining pipeline is another container, and the pressure maintaining pipeline is used as another container. With the pressure-maintaining pipeline and the gas cylinder and the pressure-maintaining pipeline being placed in the vacuum warehouse, and through pressure detection and/or gas component detection and analysis, the leakage and air tightness of the gas cylinder are detected. It should be noted that the present invention The leakage of the gas cylinder described in refers to a large leakage caused by damage to the cylinder valve. The air tightness of the gas cylinder is mainly a trace leakage. After research, it is found that the trace leakage mainly comes from the thread of the cylinder valve; further, according to With the above settings, the present invention has set up a bottle valve interface positive pressure air tightness test, a bottle valve interface negative pressure air tightness test, an alarm detection test, and a helium mass spectrometer leak detector detection test. Through the above tests, it is possible to perform the test without using a leak test liquid. It can effectively improve the accuracy of detection, reduce the purchase cost of leak test fluid, avoid the phenomenon of gas pollution caused by corrosion of gas bottles, and at the same time reduce the difficulty of operation of detection personnel and reduce the risk of misjudgment. It has high detection accuracy and the ability to Characteristics of testing the air tightness of gas cylinders.

Description of the drawings

Figure 1 is a schematic structural diagram of the present invention.

Figure 2 is a control principle block diagram of the present invention.

In the picture: 1. Vacuum warehouse body; 2. Pressure maintaining pipeline; 3. Vacuum evacuation device; 4. Gas cylinder connector; 5. Pipe pressure sensor; 6. Pipe temperature sensor; 7. Warehouse pressure sensor; 8. Oxygen content instrument; 9. Pipeline vacuum device; 10. Helium cylinder or helium pipe network; 11. First pneumatic valve; 12. Helium pressure sensor; 13. Inert gas cylinder or inert gas pipe network; 14. Second pneumatic valve; 15. Inert gas pressure sensor; 16. Electrically controlled lock; 17. Ventilation motor; 18. First tee; 19. Second tee; 20. Vacuum gauge; 21. Third pneumatic valve; 22. Pump suction alarm instrument; 23. Helium mass spectrometer leak detector; 24. Fourth pneumatic valve; 25. Fifth pneumatic valve; 26. PLC control system.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to Figures 1-2, the present invention is a gas cylinder pressure maintaining leak testing device and a pressure maintaining leak testing method. The device includes a vacuum chamber body 1, and the vacuum chamber body 1 is provided with a pressure maintaining pipeline 2; The vacuum chamber body 1 is provided with a vacuuming device 3, a vacuum chamber detection unit and a helium filling pipeline part; the pressure maintaining pipeline 2 is provided with a number of gas bottle joints 4 and pipeline pressure sensors 5. The vacuum chamber body 1 There is a pressure maintaining pipeline detection unit on the outside, and the pressure maintaining pipeline 2 is also connected to the non-helium inert gas filling pipeline part; the vacuum chamber detection unit includes a chamber pressure sensor for detecting the internal pressure of the vacuum chamber body 1 7, and an oxygen content meter 8 for detecting the oxygen content inside the vacuum warehouse body 1; the pressure-maintaining pipeline detection unit at least includes a pipeline vacuuming device 9 for vacuuming the pressure-maintaining pipeline 2. The gas detection part is used to detect whether other gases leak into the pressure-maintaining pipeline 2. The invention is suitable for detecting gas cylinders, and is specifically suitable for detecting the leakage status and air tightness of gas bottles. The leakage status of gas bottles refers to the large leakage caused by damage to the bottle valve, and the air tightness of gas bottles is mainly due to Trace leakage; especially suitable for detection of electronic grade or high-purity product gas cylinders. The present invention utilizes the characteristics that the gas cylinder is connected to the pressure-maintaining pipeline 2, and the gas bottle and the pressure-maintaining pipeline 2 are both located in the vacuum chamber body 1. Using the pressure-maintaining pipeline 2 and the vacuum warehouse body 1 as different cavities, and cooperating with pressure and/or gas component analysis, the leakage and air tightness of the gas cylinder are detected to achieve the purpose of improving detection accuracy; the present invention There is no need to use leakage fluid, which saves costs and prevents the phenomenon of gas pollution caused by corrosion of gas bottles. At the same time, it can reduce the operational difficulty of the inspection personnel and reduce the risk of misjudgment; in particular, it can detect the air tightness problem of the bottle valve, and can It is ensured that there will be no large leakage of product gas during long-distance transportation to improve customer satisfaction. It should be noted that the air tightness problem of the gas cylinder cannot be effectively detected through leak testing (the leakage amount of the leak testing liquid is small, and it is in a seeping state during the actual detection, which is not suitable for discovery and observation); but when the air tightness When the performance of the gas cylinder is poor, the product gas in the cylinder will continue to leak for a long time during the storage and transportation process, causing huge property losses to the gas cylinder user unit, and also easily causing the gas supplier to cause accidents during transportation. Leakage, resulting in compensation, etc., have always troubled gas production companies. It should be noted that the present invention is also equipped with a pipeline temperature sensor 6 that can detect the temperature in the pressure-maintaining pipeline 2, and can later be converted to eliminate the influence of the gas temperature on the gas pressure.

Further, the helium filling pipeline part includes a helium bottle or a helium pipe network 10. The helium bottle or helium pipe network 10 is connected to the vacuum chamber body 1 through a pipe. The pipe is provided with a first pneumatic valve 11 and a helium valve. Air pressure sensor 12. Through the above arrangement, helium gas from the helium bottle or helium pipe network 10 can enter the vacuum chamber body 1 for later detection purposes.

Further, the non-helium inert gas filling pipeline section includes an inert gas bottle or an inert gas pipeline network 13. The inert gas bottle or inert gas pipeline network 13 is connected to the pressure maintaining pipeline 2 through a pipeline, and a second pneumatic valve 14 is provided on the pipeline. and inert gas pressure sensor 15. Through the above arrangement, the non-helium inert gas can enter the pressure-maintaining pipeline 2, which facilitates later detection and can be distinguished from the helium in the vacuum chamber body 1; the non-helium inert gas can include neon. , argon, krypton and xenon, etc.

Furthermore, the vacuum warehouse body 1 is provided with a door with an electrically controlled lock 16 , and the vacuum warehouse body 1 is provided with a ventilation pipeline with a ventilation motor 17 . The electronically controlled lock 16 described in the present invention can be matched with the ventilation motor 17, that is, when a person enters the vacuum chamber body 1, the ventilation motor 17 is first started. When the vacuum chamber body 1 is the same as the external air, the electronically controlled lock 16 is opened to ensure the safety of people entering the site.

Further, the pressure-maintaining pipeline 2 is connected to the pipeline vacuuming device 9 through a vacuuming pipeline. The vacuuming pipeline is sequentially provided with a first tee 18, a second tee 19, and a vacuum gauge for detecting the degree of vacuum in the vacuuming pipeline. 20 and a third pneumatic valve 21; the gas detection part includes a pumping alarm 22 connected to the third end of the first tee 18, and a helium mass spectrometer leak detector 23 connected to the third end of the second tee 19 . Through the above settings, it is possible to perform vacuum processing on the pressure-maintaining pipeline 2 and detect the gas in the pressure-maintaining pipeline 2; the gas detector in the pump-type alarm 22 is consistent with the product gas in the gas cylinder: such as : When the product gas in the gas cylinder is carbon monoxide, the pump suction alarm device 22 is a CO gas detector.

Further, a fourth pneumatic valve 24 is provided between the third end of the first tee 18 and the pump suction alarm 22; a third pneumatic valve 24 is provided between the third end of the second tee 19 and the helium mass spectrometer leak detector 23. Five pneumatic valves 25.

The invention also includes a PLC control system 26. The signal input end of the PLC control system 26 is respectively connected to the pipeline pressure sensor 5, the pipeline temperature sensor 6, the warehouse pressure sensor 7, the oxygen content meter 8, the helium pressure sensor 12, and the inert gas pressure sensor. 15. Vacuum gauge 20, pump suction alarm 22 and helium mass spectrometer leak detector 23; the signal output end of the PLC control system 26 is respectively connected with the first pneumatic valve 11, the second pneumatic valve 14, the third pneumatic valve 21, the fourth Pneumatic valve 24, fifth pneumatic valve 25, vacuuming device 3, vacuum gauge 20 and pipeline vacuuming device 9; the pressure maintaining pipeline 2 is also provided with a pipeline temperature sensor 6.

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a positive pressure air tightness test of a bottle valve interface, a negative pressure air tightness test of a bottle valve interface, an alarm detection test, and a helium mass spectrometer Leak detector detection test; the positive pressure air tightness test of the bottle valve interface is used to detect whether the gas in the pressure maintaining pipeline 2 leaks into the vacuum warehouse body 1 through the bottle valve and whether the gas in the cylinder enters the pressure maintaining pipeline 2; The negative pressure air tightness test of the bottle valve interface is used to detect whether there is gas in the gas bottle or vacuum chamber body 1 and enters the pressure maintaining pipeline 2 through the bottle valve interface; the alarm detection test is used to detect whether there is gas in the gas bottle or the vacuum chamber body 1. Gas enters the pressure-maintaining pipeline 2 through the bottle valve interface; the helium mass spectrometer leak detector detection test is used to detect whether the gas in the vacuum chamber body 1 leaks into the pressure-maintaining pipeline 2 through the bottle valve. In the present invention, the above methods can be used interchangeably to improve the accuracy of the pressure maintaining leak test of gas cylinders. All the above four methods can be used, or at least one of them can be selected for use; specifically, the bottle valve described in the present invention The positive pressure air tightness test of the bottle valve is used to detect whether the bottle valve is leaking and the air tightness. The negative pressure air tightness test of the bottle valve interface is used to detect whether the bottle valve is leaking and the air tightness (negative pressure air tightness of the bottle valve interface is The detection method of the bottle valve interface positive pressure air tightness test is the same as the detection method of the bottle valve interface positive pressure air tightness test). The alarm instrument detection test is mainly used to detect whether the bottle valve leaks. The helium mass spectrometer leak detector detection test is mainly used to detect the air tightness of the bottle valve. ; The present invention can perform batch operations and detect gas bottles. When there is no problem in a batch, the entire batch can be judged to be qualified; when there is a problem in a batch, the batch can be split and tested separately to ensure To determine the specific bottle valve with the problem. The above method can effectively improve detection efficiency while ensuring detection accuracy.

Further, the positive pressure air tightness test of the bottle valve interface, the negative pressure air tightness test of the bottle valve interface, the alarm detection test and the helium mass spectrometer leak detector detection test respectively include the following steps:

The positive pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 drops, it proves that the gas in the pressure-maintaining pipeline 2 leaks through the bottle valve. to the vacuum warehouse body 1, that is, the air tightness of the bottle valve is poor; when the pipeline pressure sensor 5 detects that the gas pressure in the pressure maintaining pipeline 2 rises, it proves that the gas in the cylinder enters the pressure maintaining pipeline 2, that is, the bottle valve exists Leakage situation; when the pipeline pressure sensor 5 detects that the gas in the pressure-maintaining pipeline 2 does not change, it proves that the air tightness of the bottle valve is good and no leakage will occur;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 rises. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the vacuum chamber body 1 or the gas bottle enters the pressure-maintaining pipeline. In the pressure pipe 2, that is, the bottle valve has leakage or poor air tightness;

When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 remains unchanged, the air tightness of the bottle valve is good and no leakage occurs;

The alarm detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and release the pressure to maintain the pressure. The pressure in pipeline 2 is consistent with the pressure in vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1;

Step 4: The PLC control system 26 controls the fourth pneumatic valve 24 to open and starts the pump-type alarm 22; in step 1, the gas in the cylinder is consistent with the gas detected by the pump-type alarm 22;

Step 5: When the pump-type alarm device 22 detects the gas in the pressure-maintaining pipeline 2, it detects that the gas in the pressure-maintaining pipeline 2 contains components of the gas in the cylinder, indicating that there is leakage in the bottle valve;

It is detected that the gas in the pressure-maintaining pipeline 2 does not contain the components of the gas in the cylinder, indicating that there is no leakage in the cylinder valve;

The helium mass spectrometer leak detector detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Start the vacuuming device 3 to evacuate the vacuum chamber body 1. When the preset vacuum value is reached, close the vacuuming device 3, open the first pneumatic valve 11, and let the helium cylinder or helium pipe network 10 The helium in the chamber enters the vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2, and the pressure in the vacuum chamber body 1 is less than the pressure in the gas cylinder;

Step 4: The PLC control system 26 controls the fifth pneumatic valve 25 to open and starts the helium mass spectrometer leak detector 23;

Step 5: When the helium mass spectrometer leak detector 23 detects the gas in the pressure-maintaining pipeline 2, it is detected that the gas in the pressure-maintaining pipeline 2 contains helium components, indicating that the air tightness of the bottle valve is poor;

It is detected that the gas in the pressure-maintaining pipeline 2 does not contain helium, indicating that the air tightness of the bottle valve is good.

When the present invention is specifically used, the positive pressure air tightness test of the bottle valve interface or the negative pressure air tightness test of the bottle valve interface can be used alone, or the positive pressure air tightness test of the bottle valve interface or the negative pressure air tightness test of the bottle valve interface can be used in combination. Cross verification, or the negative pressure air tightness test of the bottle valve interface is matched with the alarm detection test, or the negative pressure air tightness test of the bottle valve interface is matched with the helium mass spectrometer leak detector detection test; or the positive pressure air tightness of the bottle valve interface is matched The test is coordinated with the alarm instrument detection test, or the bottle valve interface positive pressure air tightness test is coordinated with the alarm instrument detection test and the helium mass spectrometer leak detector detection test. It should be noted that the products in the cylinder are different, and the standards for leakage and air tightness are different; usually 1.0×10 ^-7 mbar·I/s can be used as the dividing line. When the leakage is greater than 1.0×10 ^-7 mbar·I/ s represents leakage; when the leakage amount is equal to or less than 1.0×10 ^{- 7} mbar·I/s, the air tightness is poor; especially when the negative pressure air tightness test of the bottle valve interface is used, if an unqualified condition occurs, the alarm can be The instrument testing test and/or the helium mass spectrometer leak detector testing test are coordinated to determine the specific leakage or air tightness problem of the bottle valve; if the bottle valve leaks, you can choose to repair or replace it. For sexual problems, the threads can be maintained to prevent the cylinder from flowing into the market while leaking product gas.

Further, after the test is completed, when personnel need to enter, the ventilation motor 17 is turned on, and the oxygen content meter 8 detects the oxygen content in the vacuum chamber body 1 in real time. When the oxygen content reaches the human body entry standard, the electric control lock 16 is The barn door is open. In order to ensure the safety of personnel entering the vacuum chamber 1, before the personnel enter the vacuum chamber 1, the ventilation motor 17 is first turned on. When the ventilation motor 17 is turned on, the oxygen content meter 8 is implemented to detect the oxygen content in the vacuum chamber 1. , when the oxygen content meets the human body entry standard, the electronic control lock 16 is opened, and personnel enter the vacuum chamber body 1 through the chamber door to operate.

In order to explain the present invention more clearly, it will be further described with reference to specific embodiments. Specific examples are as follows:

Example 1

A pressure-maintaining leak test device for gas cylinders, including a vacuum chamber body 1, which is provided with a pressure-maintaining pipeline 2; the vacuum chamber body 1 is provided with a vacuum device 3 and a vacuum chamber detection unit and a helium filling pipeline part; the pressure-maintaining pipeline 2 is provided with several gas bottle joints 4 and pipeline pressure sensors 5. The outside of the vacuum warehouse body 1 is provided with a pressure-maintaining pipeline detection unit, and the pressure-maintaining pipeline 2 is also connected to non- The helium inert gas filling pipeline is connected; the vacuum chamber detection unit includes a chamber pressure sensor 7 for detecting the internal pressure of the vacuum chamber body 1, and a chamber pressure sensor 7 for detecting the oxygen content inside the vacuum chamber body 1 Oxygen content meter 8; the pressure-maintaining pipeline detection unit at least includes a pipeline vacuuming device 9 for evacuating the pressure-maintaining pipeline 2, and a gas detection part for detecting whether other gases leak into the pressure-maintaining pipeline 2. The helium filling pipeline part includes a helium bottle or a helium pipe network 10. The helium bottle or helium pipe network 10 is connected to the vacuum chamber body 1 through a pipe. The pipe is provided with a first pneumatic valve 11 and a helium pressure sensor. 12. The non-helium inert gas filling pipeline part includes an inert gas bottle or an inert gas pipe network 13. The inert gas bottle or the inert gas pipe network 13 is connected to the pressure maintaining pipe 2 through a pipe. The pipe is provided with a second pneumatic valve 14 and an inert gas pipe. Pressure sensor 15. The vacuum warehouse body 1 is provided with a door with an electronically controlled lock 16 , and the vacuum warehouse body 1 is provided with a ventilation pipeline with a ventilation motor 17 . The pressure-maintaining pipeline 2 is connected to the pipeline vacuuming device 9 through a vacuuming pipeline. The vacuuming pipeline is sequentially provided with a first tee 18, a second tee 19, a vacuum gauge 20 for detecting the vacuum degree in the vacuuming pipeline, and a third Three pneumatic valves 21; the gas detection part includes a pump-type alarm 22 connected to the third end of the first tee 18, and a helium mass spectrometer leak detector 23 connected to the third end of the second tee 19. A fourth pneumatic valve 24 is provided between the third end of the first tee 18 and the pump suction alarm 22; a fifth pneumatic valve 24 is provided between the third end of the second tee 19 and the helium mass spectrometer leak detector 23 25. It also includes a PLC control system 26. The signal input terminals of the PLC control system 26 are respectively connected to the pipeline pressure sensor 5, the pipeline temperature sensor 6, the warehouse pressure sensor 7, the oxygen content meter 8, the helium pressure sensor 12, the inert gas pressure sensor 15, Vacuum gauge 20, pump suction alarm 22 and helium mass spectrometer leak detector 23; the signal output end of the PLC control system 26 is connected to the first pneumatic valve 11, the second pneumatic valve 14, the third pneumatic valve 21 and the fourth pneumatic valve respectively. 24. The fifth pneumatic valve 25, vacuuming device 3, vacuum gauge 20 and pipeline vacuuming device 9; the pressure maintaining pipeline 2 is also provided with a pipeline temperature sensor 6.

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method is a positive pressure air tightness test of a bottle valve interface, which includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 drops, it proves that the gas in the pressure-maintaining pipeline 2 leaks through the bottle valve. to the vacuum warehouse body 1, that is, the air tightness of the bottle valve is poor; at this time, check and maintain the poor air tightness of the bottle valve.

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate.

Example 2

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method is a positive pressure air tightness test of a bottle valve interface, which includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the cylinder enters the pressure-maintaining pipeline 2 , that is, the bottle valve is leaking; at this time, check, maintain or replace the bottle valve for leakage.

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate.

Example 3

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method is a positive pressure air tightness test of a bottle valve interface, which includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas in the pressure-maintaining pipeline 2 does not change, it proves that the air tightness of the bottle valve is good, and it does not Leakage may occur;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate.

Example 4

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a positive pressure air tightness test of a bottle valve interface and a negative pressure air tightness test of a bottle valve interface;

The positive pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas in the pressure-maintaining pipeline 2 does not change, it proves that the air tightness of the bottle valve is good, and it does not Leakage may occur;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 is rising. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 remains unchanged, the air tightness of the bottle valve is good and no leakage will occur. Phenomenon.

The above cross-validation proves that the air tightness of the bottle valve is good and no leakage occurs.

Example 5

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a positive pressure air tightness test of a bottle valve interface, a negative pressure air tightness test of a bottle valve interface, and an alarm detection test;

The positive pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the cylinder enters the pressure-maintaining pipeline 2 , that is, there is leakage in the bottle valve;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 rises. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the vacuum chamber body 1 or the gas bottle enters the pressure-maintaining pipeline. In the pressure pipe 2, that is, the bottle valve has leakage or poor air tightness;

The alarm detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and release the pressure to maintain the pressure. The pressure in pipeline 2 is consistent with the pressure in vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1;

Step 4: The PLC control system 26 controls the fourth pneumatic valve 24 to open and starts the pump-type alarm 22; in step 1, the gas in the cylinder is consistent with the gas detected by the pump-type alarm 22;

Step 5: When the pump-type alarm device 22 detects the gas in the pressure-maintaining pipeline 2, it detects that the gas in the pressure-maintaining pipeline 2 contains components of the gas in the cylinder, indicating that there is leakage in the cylinder valve.

The above cross-validation proves that the bottle valve is leaking, so it needs to be inspected, maintained or replaced.

Example 6

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a positive pressure air tightness test of a bottle valve interface, a negative pressure air tightness test of a bottle valve interface, and a helium mass spectrometer leak detector detection test. Include the following steps respectively:

The positive pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 drops, it proves that the gas in the pressure-maintaining pipeline 2 leaks through the bottle valve. to the vacuum chamber body 1, that is, the air tightness of the bottle valve is poor;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 rises. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the vacuum chamber body 1 or the gas bottle enters the pressure-maintaining pipeline. In the pressure pipe 2, that is, the bottle valve has leakage or poor air tightness;

The helium mass spectrometer leak detector detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Start the vacuuming device 3 to evacuate the vacuum chamber body 1. When the preset vacuum value is reached, close the vacuuming device 3, open the first pneumatic valve 11, and let the helium cylinder or helium pipe network 10 The helium in the chamber enters the vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2, and the pressure in the vacuum chamber body 1 is less than the pressure in the gas cylinder;

Step 4: The PLC control system 26 controls the fifth pneumatic valve 25 to open and starts the helium mass spectrometer leak detector 23;

Step 5: When the helium mass spectrometer leak detector 23 detects the gas in the pressure-maintaining pipeline 2, it is detected that the gas in the pressure-maintaining pipeline 2 contains helium components, indicating that the air tightness of the bottle valve is poor.

After the test is completed, when personnel need to enter, the ventilation motor 17 is turned on, and the oxygen content meter 8 detects the oxygen content in the vacuum chamber body 1 in real time. When the oxygen content reaches the human body entry standard, the chamber door with the electrically controlled lock 16 Open.

The above cross-validation proves that the bottle valve is leaking, so it needs to be inspected, maintained or replaced.

Example 7

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes a negative pressure air tightness test of the bottle valve interface and an alarm detection test;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 rises. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the vacuum chamber body 1 or the gas bottle enters the pressure-maintaining pipeline. In the pressure pipe 2, that is, the bottle valve has leakage or poor air tightness;

The alarm detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and release the pressure to maintain the pressure. The pressure in pipeline 2 is consistent with the pressure in vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1;

Step 4: The PLC control system 26 controls the fourth pneumatic valve 24 to open and starts the pump-type alarm 22; in step 1, the gas in the cylinder is consistent with the gas detected by the pump-type alarm 22;

Step 5: When the pump-type alarm device 22 detects the gas in the pressure-maintaining pipeline 2, it detects that the gas in the pressure-maintaining pipeline 2 does not contain the gas components in the cylinder, indicating that there is no leakage in the cylinder valve.

The above cross-validation proves that the bottle valve does not leak, but it has the defect of poor air tightness, so the bottle valve needs to be inspected and maintained.

Example 8

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a negative pressure air tightness test of the bottle valve interface, an alarm detection test, and a helium mass spectrometer leak detector detection test;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 rises. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 rises, it proves that the gas in the vacuum chamber body 1 or the gas bottle enters the pressure-maintaining pipeline. In the pressure pipe 2, that is, the bottle valve has leakage or poor air tightness;

The alarm detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and release the pressure to maintain the pressure. The pressure in pipeline 2 is consistent with the pressure in vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1;

Step 4: The PLC control system 26 controls the fourth pneumatic valve 24 to open and starts the pump-type alarm 22; in step 1, the gas in the cylinder is consistent with the gas detected by the pump-type alarm 22;

Step 5: When the pump-type alarm device 22 detects the gas in the pressure-maintaining pipeline 2, it detects that the gas in the pressure-maintaining pipeline 2 contains components of the gas in the cylinder, indicating that there is leakage in the bottle valve;

The helium mass spectrometer leak detector detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Start the vacuuming device 3 to evacuate the vacuum chamber body 1. When the preset vacuum value is reached, close the vacuuming device 3, open the first pneumatic valve 11, and let the helium cylinder or helium pipe network 10 The helium in the chamber enters the vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2, and the pressure in the vacuum chamber body 1 is less than the pressure in the gas cylinder;

Step 4: The PLC control system 26 controls the fifth pneumatic valve 25 to open and starts the helium mass spectrometer leak detector 23;

Step 5: When the helium mass spectrometer leak detector 23 detects the gas in the pressure-maintaining pipeline 2, it is detected that the gas in the pressure-maintaining pipeline 2 does not contain helium, indicating that the air tightness of the bottle valve is good.

After the test is completed, when personnel need to enter, the ventilation motor 17 is turned on, and the oxygen content meter 8 detects the oxygen content in the vacuum chamber body 1 in real time. When the oxygen content reaches the human body entry standard, the chamber door with the electrically controlled lock 16 Open.

The above cross-verification proves that the bottle valve is leaking and does not have a defect of poor air tightness. Therefore, the bottle valve needs to be inspected, maintained or replaced.

Example 9

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a negative pressure air tightness test of the bottle valve interface, an alarm detection test, and a helium mass spectrometer leak detector detection test;

The negative pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Disabled;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 is rising. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 remains unchanged, the air tightness of the bottle valve is good and no leakage will occur. Phenomenon;

The alarm detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and release the pressure to maintain the pressure. The pressure in pipeline 2 is consistent with the pressure in vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1;

Step 4: The PLC control system 26 controls the fourth pneumatic valve 24 to open and starts the pump-type alarm 22; in step 1, the gas in the cylinder is consistent with the gas detected by the pump-type alarm 22;

Step 5: When the pump-type alarm device 22 detects the gas in the pressure-maintaining pipeline 2, it detects that the gas in the pressure-maintaining pipeline 2 does not contain the components of the gas in the cylinder, indicating that there is no leakage from the bottle valve;

The helium mass spectrometer leak detector detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Start the vacuuming device 3 to evacuate the vacuum chamber body 1. When the preset vacuum value is reached, close the vacuuming device 3, open the first pneumatic valve 11, and let the helium cylinder or helium pipe network 10 The helium in the chamber enters the vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2, and the pressure in the vacuum chamber body 1 is less than the pressure in the gas cylinder;

Step 4: The PLC control system 26 controls the fifth pneumatic valve 25 to open and starts the helium mass spectrometer leak detector 23;

Step 5: When the helium mass spectrometer leak detector 23 detects the gas in the pressure-maintaining pipeline 2, it is detected that the gas in the pressure-maintaining pipeline 2 does not contain helium, indicating that the air tightness of the bottle valve is good.

After the test is completed, when personnel need to enter, the ventilation motor 17 is turned on, and the oxygen content meter 8 detects the oxygen content in the vacuum chamber body 1 in real time. When the oxygen content reaches the human body entry standard, the chamber door with the electrically controlled lock 16 Open.

The above cross-validation proves that there is no leakage in the bottle valve and the air tightness is good.

Example 10

A gas cylinder pressure maintaining leak test device, the structure of which is the same as that of Embodiment 1;

A pressure-maintaining leak test method of a gas cylinder pressure-maintaining leak test device. The pressure-maintaining leak test method includes: a positive pressure air tightness test of the cylinder valve interface and a helium mass spectrometer leak detector detection test, which respectively include the following steps:

The positive pressure air tightness test of the bottle valve interface includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 drops, it proves that the gas in the pressure-maintaining pipeline 2 leaks through the bottle valve. to the vacuum chamber body 1, that is, the air tightness of the bottle valve is poor;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate;

The helium mass spectrometer leak detector detection test includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Start the vacuuming device 3 to evacuate the vacuum chamber body 1. When the preset vacuum value is reached, close the vacuuming device 3, open the first pneumatic valve 11, and let the helium cylinder or helium pipe network 10 The helium in the chamber enters the vacuum chamber body 1;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2, and the pressure in the vacuum chamber body 1 is less than the pressure in the gas cylinder;

Step 4: The PLC control system 26 controls the fifth pneumatic valve 25 to open and starts the helium mass spectrometer leak detector 23;

Step 5: When the helium mass spectrometer leak detector 23 detects the gas in the pressure-maintaining pipeline 2, it is detected that the gas in the pressure-maintaining pipeline 2 contains helium components, indicating that the air tightness of the bottle valve is poor;

After the test is completed, when personnel need to enter, the ventilation motor 17 is turned on, and the oxygen content meter 8 detects the oxygen content in the vacuum chamber body 1 in real time. When the oxygen content reaches the human body entry standard, the chamber door with the electrically controlled lock 16 Open.

The above cross-validation proves that the bottle valve does not leak, but it has the defect of poor air tightness, so the bottle valve needs to be inspected and maintained.

The invention is also suitable for large-scale testing of gas bottles in batches. If there is no problem with the gas bottles in the batch, then there is no problem with the entire batch; if there is a problem with the batch, the batch will be dismantled. After splitting, the gas bottles with no problems are eliminated, and the remaining gas bottles are split again to achieve the purpose of improving detection efficiency; the present invention analyzes the pressure and/or gas components to obtain the leakage or air tightness of the gas cylinder. It does not require empirical judgment to achieve the purpose of avoiding misjudgment, and it can also improve the accuracy of detection. Compared with the existing technology, it can reduce the purchase cost of leak test liquid and avoid the phenomenon of gas pollution caused by corrosion of gas bottles. At the same time, It can reduce the operational difficulty of the inspection personnel and reduce the risk of misjudgment. It has the characteristics of high detection accuracy and the ability to detect the air tightness of the gas cylinder.

Test example 1

The present invention adopts the positive pressure air tightness test of the bottle valve interface, which includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Fill the test gas into the pressure-maintaining pipe 2, so that the gas pressure in the pressure-maintaining pipe 2 is greater than the pressure in the vacuum chamber body 1, and at the same time less than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is closed; The volume of the gas cylinder is 40L, the pressure is 13.52MPA, and the filled product gas is electronic grade carbon dioxide; the pressure in the pressure-maintaining pipeline 2 is 7.5MPA, and the vacuum chamber pressure is atmospheric pressure;

Step 3: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 fluctuates. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 drops by 1KPA, it proves that the gas in the pressure-maintaining pipeline 2 passes through the bottle. The valve leaks into the vacuum chamber body 1, that is, the air tightness of the bottle valve is poor;

Step 4: After the above detection is completed, recover the test gas in the pressure-maintaining pipeline 2, or use the pipeline vacuum device 9 to evacuate;

Through the above method, it can be proved that the cylinder valve of the gas cylinder has air tightness problems; when tested through conventional leakage methods, no leakage or leakage was found, so the cylinder valve of the gas cylinder was deemed to be qualified.

Test example 2

The present invention adopts the negative pressure air tightness test of the bottle valve interface, which includes the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure-maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and relieve the pressure, and finally use the pipeline The vacuuming device 9 performs vacuuming on the pressure-maintaining pipeline 2, and determines the vacuum degree in the pressure-maintaining pipeline 2 through the vacuum gauge 20;

Step 3: The cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1, and the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2; the cylinder valve of the gas cylinder is in a closed state. Closed state; the volume of the gas cylinder is 40L, the pressure is 13.52MPA, and the filled product gas is electronic grade carbon monoxide; the vacuum pressure in the pressure-maintaining pipeline 2 is -90kPa, and the vacuum chamber pressure is atmospheric pressure;

Step 4: Use the pipeline pressure sensor 5 to detect whether the gas pressure in the pressure-maintaining pipeline 2 has increased. When the pipeline pressure sensor 5 detects that the gas pressure in the pressure-maintaining pipeline 2 has increased by 5kPa, it is proved that the gas in the vacuum chamber body 1 or the gas bottle Entering the pressure-maintaining pipeline 2, that is, the bottle valve has leakage or poor air tightness;

Further, the alarm instrument detection test is used, including the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Open the second pneumatic valve 14, and the non-helium inert gas in the inert gas bottle or inert gas pipe network 13 enters the pressure maintaining pipeline 2 for gas replacement. After replacement, close the second pneumatic valve 14 and release the pressure to maintain the pressure. The pressure in pipeline 2 is consistent with the pressure in vacuum chamber body 1; the pressures in pressure-maintaining pipeline 2 and vacuum chamber body 1 are both atmospheric pressure;

Step 3: The cylinder valve of the gas cylinder is closed, and the pressure in the gas cylinder is greater than the pressure in the vacuum chamber body 1;

Step 4: The PLC control system 26 controls the fourth pneumatic valve 24 to open and starts the pump-type alarm 22; the pump-type alarm 22 is a CO gas detector;

Step 5: When the pump-type alarm device 22 detects the gas in the pressure-maintaining pipeline 2, it detects that the gas in the pressure-maintaining pipeline 2 does not contain the components of the gas in the cylinder, indicating that there is no leakage from the bottle valve;

Furthermore, a helium mass spectrometer leak detector detection test is used, including the following steps:

Step 1: Connect the cylinder valve of the gas cylinder to the filling row of the gas cylinder connector 4 in the pressure maintaining pipeline 2;

Step 2: Start the vacuuming device 3 to evacuate the vacuum chamber body 1. When the preset vacuum value is reached, close the vacuuming device 3, open the first pneumatic valve 11, and let the helium cylinder or helium pipe network 10 The helium in the vacuum chamber enters the vacuum chamber body 1, and the pressure of the pressure maintaining pipe 2 is atmospheric pressure;

Step 3: The cylinder valve of the gas cylinder is closed, the pressure in the vacuum chamber body 1 is greater than the pressure in the pressure maintaining pipe 2, and the pressure in the vacuum chamber body 1 is less than the pressure in the gas cylinder;

Step 4: The PLC control system 26 controls the fifth pneumatic valve 25 to open and starts the helium mass spectrometer leak detector 23;

Step 5: When the helium mass spectrometer leak detector 23 detects the gas in the pressure-maintaining pipeline 2, it is detected that the gas in the pressure-maintaining pipeline 2 contains helium components, and the detected concentration is 1.0×10 ^-7 mbar·I/s, indicating the existence of the bottle valve. Poor air tightness.

Through the above method, it can be proved that the cylinder valve of the gas cylinder has air tightness problems; when tested through conventional leakage methods, no leakage or leakage was found, so the cylinder valve of the gas cylinder was deemed to be qualified.

The above two test examples can prove that the detection method of the present invention can detect the leakage problem and air tightness of gas bottles without using leakage liquid, especially in detecting the air tightness of gas bottles, its accuracy is high on existing technology.

Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art will understand that various changes, modifications, and substitutions can be made to these embodiments without departing from the principles and spirit of the invention. and modifications, the scope of the invention is defined by the appended claims and their equivalents.

Claims (10)

1. The utility model provides a gas cylinder pressurize leak test device, includes vacuum storehouse body (1), its characterized in that: a pressure maintaining pipeline (2) is arranged in the vacuum bin body (1);

The vacuum bin body (1) is provided with a vacuumizing device (3), a vacuum bin detection unit and a helium filling pipeline part;

the pressure maintaining pipeline (2) is provided with a plurality of gas bottle connectors (4) and pipeline pressure sensors (5), a pressure maintaining pipeline detection unit is arranged outside the vacuum bin body (1), and the pressure maintaining pipeline (2) is also connected with a non-helium inert gas filling pipeline part;

the vacuum bin detection unit comprises a bin body pressure sensor (7) for detecting the internal pressure of the vacuum bin body (1), and an oxygen content meter (8) for detecting the internal oxygen content of the vacuum bin body (1);

the pressure maintaining pipeline detection unit at least comprises a pipeline vacuumizing device (9) for vacuumizing the pressure maintaining pipeline (2) and a gas detection part for detecting whether other gases leak into the pressure maintaining pipeline (2).

2. The gas cylinder pressure maintaining leak testing device according to claim 1, wherein: the helium filling pipeline part comprises a helium bottle or a helium pipe network (10), the helium bottle or the helium pipe network (10) is connected with the vacuum bin body (1) through a pipeline, and a first pneumatic valve (11) and a helium pressure sensor (12) are arranged on the pipeline.

3. The gas cylinder pressure maintaining leak testing device according to claim 1, wherein: the non-helium inert gas filling pipeline part comprises an inert gas cylinder or an inert gas pipe network (13), the inert gas cylinder or the inert gas pipe network (13) is connected with the pressure maintaining pipeline (2) through a pipeline, and a second pneumatic valve (14) and an inert gas pressure sensor (15) are arranged on the pipeline.

4. The gas cylinder pressure maintaining leak testing device according to claim 1, wherein: the vacuum bin body (1) is provided with a bin door with an electric control lock (16), and the vacuum bin body (1) is provided with a ventilation pipeline with a ventilation motor (17).

5. The gas cylinder pressure maintaining leak testing device according to claim 1, wherein: the pressure maintaining pipeline (2) is connected with the pipeline vacuumizing device (9) through a vacuumizing pipeline, and a first tee joint (18), a second tee joint (19), a vacuum gauge (20) for detecting the vacuum degree in the vacuumizing pipeline and a third pneumatic valve (21) are sequentially arranged on the vacuumizing pipeline;

the gas detection part comprises a pumping type alarm (22) connected with the third end of the first tee joint (18), and a helium mass spectrum leak detector (23) connected with the third end of the second tee joint (19).

6. The gas cylinder pressure maintaining leak testing device according to claim 5, wherein: a fourth pneumatic valve (24) is arranged between the third end of the first tee joint (18) and the pumping type alarm instrument (22); a fifth pneumatic valve (25) is arranged between the third end of the second tee joint (19) and the helium mass spectrometer leak detector (23).

7. The gas cylinder pressure maintaining leak testing device according to claim 1, wherein: the device also comprises a PLC control system (26), wherein the signal input end of the PLC control system (26) is respectively connected with a pipeline pressure sensor (5), a pipeline temperature sensor (6), a bin body pressure sensor (7), an oxygen content meter (8), a helium pressure sensor (12), an inert gas pressure sensor (15), a vacuum gauge (20), a pumping type alarm instrument (22) and a helium mass spectrometer leak detector (23); the signal output end of the PLC control system (26) is respectively connected with the first pneumatic valve (11), the second pneumatic valve (14), the third pneumatic valve (21), the fourth pneumatic valve (24), the fifth pneumatic valve (25), the vacuumizing device (3), the vacuum gauge (20) and the pipeline vacuumizing device (9); the pressure maintaining pipeline (2) is also provided with a pipeline temperature sensor (6).

8. A pressure maintaining and leak testing method of the pressure maintaining and leak testing device for gas cylinders according to any one of claims 1 to 7, characterized in that: the pressure maintaining leakage testing method comprises the following steps: the method comprises the following steps of a positive pressure air tightness test of a valve interface, a negative pressure air tightness test of the valve interface, a detection test of an alarm instrument and a detection test of a helium mass spectrometer leak detector;

the positive pressure airtight test of the bottle valve interface is used for detecting whether gas in the pressure maintaining pipeline (2) leaks into the vacuum bin body (1) through the bottle valve and whether the gas of the gas bottle enters the pressure maintaining pipeline (2);

the cylinder valve interface negative pressure air tightness test is used for detecting whether gas in the gas cylinder or the vacuum bin body (1) enters the pressure maintaining pipeline (2) through the cylinder valve interface;

the alarm detection test is used for detecting whether gas in the gas cylinder enters the pressure maintaining pipeline (2) through the cylinder valve interface;

the helium mass spectrometer leak detector detection test is used for detecting whether the gas in the vacuum bin body (1) leaks into the pressure maintaining pipeline (2) through the bottle valve.

9. The pressure maintaining leak testing method of the gas cylinder pressure maintaining leak testing device according to claim 8, characterized in that: the positive pressure air tightness test of the valve interface, the negative pressure air tightness test of the valve interface, the detection test of the alarm instrument and the detection test of the helium mass spectrometer leak detector respectively comprise the following steps:

The positive pressure air tightness test of the bottle valve interface comprises the following steps:

step 1: connecting a cylinder valve of a gas cylinder with a filling row of a gas cylinder joint (4) in a pressure maintaining pipeline (2);

step 2: filling test gas into the pressure maintaining pipeline (2), so that the gas pressure in the pressure maintaining pipeline (2) is higher than the pressure in the vacuum bin body (1) and is lower than the pressure in the gas cylinder; the cylinder valve of the gas cylinder is in a closed state;

step 3: detecting whether the pressure of the gas in the pressure maintaining pipeline (2) fluctuates or not through the pipeline pressure sensor (5), and when the pipeline pressure sensor (5) detects that the pressure of the gas in the pressure maintaining pipeline (2) is reduced, proving that the gas in the pressure maintaining pipeline (2) leaks into the vacuum bin body (1) through the bottle valve, namely the air tightness of the bottle valve is poor; when the pipeline pressure sensor (5) detects that the pressure of the gas in the pressure maintaining pipeline (2) rises, the gas in the gas cylinder enters the pressure maintaining pipeline (2), namely, the leakage condition of the cylinder valve is proved; when the pipeline pressure sensor (5) detects that the gas in the pressure maintaining pipeline (2) is not changed, the air tightness of the bottle valve is proved to be good, and the leakage phenomenon is avoided;

step 4: after the detection is finished, the test gas in the pressure maintaining pipeline (2) is recovered, or the pipeline vacuumizing device (9) is utilized to vacuumize;

The negative pressure air tightness test of the bottle valve interface comprises the following steps:

step 1: connecting a cylinder valve of a gas cylinder with a filling row of a gas cylinder joint (4) in a pressure maintaining pipeline (2);

step 2: opening a second pneumatic valve (14), enabling non-helium inert gas in an inert gas cylinder or an inert gas pipe network (13) to enter a pressure maintaining pipeline (2) for gas replacement, closing the second pneumatic valve (14) and releasing pressure after the replacement, and finally vacuumizing the pressure maintaining pipeline (2) by using a pipeline vacuumizing device (9), and determining the vacuum degree in the pressure maintaining pipeline (2) by using a vacuum gauge (20);

step 3: the cylinder valve of the gas cylinder is in a closed state, the pressure in the gas cylinder is larger than the pressure in the vacuum chamber body (1), and the pressure in the vacuum chamber body (1) is larger than the pressure in the pressure maintaining pipeline (2); the cylinder valve of the gas cylinder is in a closed state;

step 4: detecting whether the pressure of the gas in the pressure maintaining pipeline (2) rises or not through a pipeline pressure sensor (5), and when the pipeline pressure sensor (5) detects that the pressure of the gas in the pressure maintaining pipeline (2) rises, proving that the gas in the vacuum bin body (1) or the gas cylinder enters the pressure maintaining pipeline (2), namely, the condition that a cylinder valve has leakage or poor air tightness;

when the pipeline pressure sensor (5) detects that the gas pressure in the pressure maintaining pipeline (2) is unchanged, the air tightness of the bottle valve is good, and the leakage phenomenon can not occur;

The alarm detection test comprises the following steps:

step 1: connecting a cylinder valve of a gas cylinder with a filling row of a gas cylinder joint (4) in a pressure maintaining pipeline (2);

step 2: opening a second pneumatic valve (14), enabling non-helium inert gas in an inert gas cylinder or an inert gas pipe network (13) to enter a pressure maintaining pipeline (2) for gas replacement, closing the second pneumatic valve (14) after replacement and releasing pressure, so that the pressure in the pressure maintaining pipeline (2) is consistent with the pressure in a vacuum bin body (1);

step 3: the cylinder valve of the gas cylinder is in a closed state, and the pressure in the gas cylinder is higher than the pressure in the vacuum bin body (1);

step 4: the PLC control system (26) controls the fourth pneumatic valve (24) to be opened and starts the pumping type alarm (22); the gas in the gas cylinder in the step 1 is consistent with the gas detected by the pumping type alarm (22);

step 5: when the pumping type alarm (22) detects the gas in the pressure maintaining pipeline (2), detecting that the gas in the pressure maintaining pipeline (2) contains the gas component in the gas cylinder, and indicating the condition that the cylinder valve is leaked;

detecting that the gas in the pressure maintaining pipeline (2) does not contain the gas component in the gas cylinder, and indicating that the gas cylinder valve does not leak;

the helium mass spectrometer leak detector detection test comprises the following steps:

Step 1: connecting a cylinder valve of a gas cylinder with a filling row of a gas cylinder joint (4) in a pressure maintaining pipeline (2);

step 2: starting a vacuumizing device (3), vacuumizing the vacuum bin body (1), closing the vacuumizing device (3) when a preset vacuum value is reached, and opening a first pneumatic valve (11) to enable helium in a helium bottle or a helium pipe network (10) to enter the vacuum bin body (1);

step 3: the cylinder valve of the gas cylinder is in a closed state, the pressure in the vacuum chamber body (1) is larger than the pressure in the pressure maintaining pipeline (2), and the pressure in the vacuum chamber body (1) is smaller than the pressure in the gas cylinder;

step 4: a PLC control system (26) controls the opening of a fifth pneumatic valve (25) and starts a helium mass spectrometer leak detector (23);

step 5: when the helium mass spectrometer leak detector (23) detects the gas in the pressure maintaining pipeline (2), detecting that the gas in the pressure maintaining pipeline (2) contains helium components, and indicating that the bottle valve has poor air tightness;

the detection of the absence of helium in the gas in the pressure maintaining pipe (2) indicates that the cylinder valve has good air tightness.

10. The pressure maintaining leak testing method of the gas cylinder pressure maintaining leak testing apparatus as defined in claim 9, wherein: after the test is finished, when a person needs to enter, a ventilation motor (17) is started, an oxygen content meter (8) detects the oxygen content in the vacuum bin body (1) in real time, and when the oxygen content reaches the human body entry standard, a bin door with a control lock (16) is opened.