Sampling Apparatus and Method for Sulfur Hexafluoride and its Mixed Gases in Electrical Equipment

Abstract

This invention relates to a sampling device and method for sulfur hexafluoride (SF6) and its mixed gases used in electrical equipment. The sampling device includes an equipment connection module, a sampling module, a gas filling module, and a vacuuming module. The equipment connection module, used to connect the electrical equipment and the gas sampler, consists of an equipment connection valve, a diaphragm pump, and corresponding pipelines. The sampling module, used for gas buffering, consists of a sampling cylinder, a pressure detection unit, a sampling valve, a gas filling valve, a tail gas valve, and corresponding pipelines. The gas filling module, used to fill the sampling container, consists of a booster pump, a sampling container connection valve, and corresponding pipelines. The vacuuming module, used for vacuuming and tail gas collection, consists of a vacuum pump, a tail gas collection device, and its connection valves. The sampling method utilizes appropriate flushing and vacuuming methods when the gas pressure is higher or lower than 0.2 MPa. This sampling device and method can improve the accuracy of sampling sulfur hexafluoride gas or sulfur hexafluoride mixed insulating gases.

Description

Technical Field

[0001] This invention belongs to the field of power equipment testing technology, specifically relating to a sampling device and method for sulfur hexafluoride and its mixed gases used in electrical equipment. Background Technology

[0002] Operating electrical equipment requires testing of various parameters of sulfur hexafluoride (SF6) gas or SF6 mixed insulating gases to determine its operational status. Laboratory testing equipment offers significantly higher accuracy than portable instruments, necessitating the collection of gas samples for laboratory analysis. However, existing sampling processes, due to incomplete sampling devices or unscientific methods, struggle to ensure sample integrity, resulting in low accuracy and reliability. Consequently, the sampled gas cannot accurately reflect the gas conditions within the chamber. Therefore, further research and development of SF6 gas sampling devices and methods for electrical applications are necessary. Summary of the Invention

[0003] The purpose of this invention is to provide a sampling device and method for sulfur hexafluoride and its mixed gases for electrical equipment, which can improve the accuracy of sampling sulfur hexafluoride gas or sulfur hexafluoride mixed insulating gas.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is: a sampling device for sulfur hexafluoride and its mixed gases for electrical equipment, comprising a device connection module, a sampling module, a gas filling module, and a vacuum module; the device connection module is used for connecting to electrical equipment and sampling gas, and mainly consists of a device connection valve, a diaphragm pump, and corresponding pipelines; the sampling module is used for gas buffering, and mainly consists of a sampling cylinder, a pressure detection unit, a sampling valve, a gas filling valve, a tail gas valve, and corresponding pipelines; the gas filling module is used for filling the sampling container with gas, and mainly consists of a booster pump, a sampling container connection valve, and corresponding pipelines; the vacuum module is used for vacuuming the sampling device, sampling container, and pipelines, and for tail gas collection, and mainly consists of a vacuum pump, a tail gas collection device connection valve, and a tail gas collection device.

[0005] Furthermore, the equipment connection valve, sampling valve, inflation valve, exhaust gas valve, sampling container connection valve, and exhaust gas collection device connection valve are all three-way valves; the first port of the equipment connection valve is used to connect electrical equipment or gas cylinders / storage tanks; the second port of the equipment connection valve is connected to the first port of the sampling valve via a corresponding pipeline; the third port of the equipment connection valve is connected to the third port of the sampling valve via a diaphragm pump and a corresponding pipeline; the second port of the sampling valve is connected to the sampling cylinder via a corresponding pipeline; the first port of the sampling container connection valve is used to connect the sampling container; the second port of the sampling container connection valve is connected to the sampling cylinder via a corresponding pipeline. The pipeline connects to the first port of the inflation valve; the sampling container connects to the third port of the valve via a booster pump and corresponding pipelines, and the second port of the inflation valve connects to the sampling cylinder via corresponding pipelines; the exhaust gas collection device connects to the first port of the valve via a valve; the exhaust gas collection device connects to the second port of the valve via a corresponding pipeline, and the exhaust gas collection device connects to the first port of the exhaust gas valve via a valve; the exhaust gas collection device connects to the third port of the valve via a vacuum pump and corresponding pipelines, and the exhaust gas valve connects to the sampling cylinder via corresponding pipelines; the pressure detection unit is installed on the sampling cylinder.

[0006] This invention also provides a sampling method based on the aforementioned sulfur hexafluoride and its mixed gas sampling device for electrical equipment. When sampling is performed on the electrical equipment, and the gas pressure is higher than 0.2 MPa, a flushing method is used for sampling. The sampling steps are as follows:

[0007] a) Connect the sampling container, exhaust gas collection device and sampling module. When it is necessary to pressurize and store the sampled gas, a booster pump also needs to be connected. Connect the sampling container to the charging and discharging port of the electrical equipment using the sampling pipeline.

[0008] b) Close the tail gas valve, open the charging and discharging valve of the electrical equipment, as well as the equipment connection valve, sampling valve, charging valve, and sampling container connection valve; make the gauge pressure of the sampling cylinder greater than 0.1MPa, close the equipment connection valve, open the tail gas valve and tail gas collection device connection valve, and use the tail gas collection device to collect the gas in the sampling device until the gauge pressure of the sampling cylinder is 0.01MPa.

[0009] c) Repeat step b) twice to flush out residual gas in the sampling system. When the sample needs to be tested for gas-mix ratio, multiple flushes are required.

[0010] d) When it is not necessary to pressurize and store the sample, close the tail gas valve and open the equipment connection valve to allow the gas in the equipment to fill the sampling container. The gauge pressure of the sampling cylinder is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0011] e) When it is necessary to pressurize and store the sample, close the tail gas valve and open the equipment connection valve to allow the gas in the equipment to fill the sampling container. When the pressure on the sampling cylinder gauge is consistent with the pressure of the electrical equipment, turn on the booster pump to pressurize and store the sample in the sampling container to the set sampling pressure; however, prevent the storage pressure from being too high, which may cause the sample to liquefy.

[0012] f) After sampling is completed, close the electrical equipment charging / discharging valve, the equipment connection valve of the sampling device, the gas sampling valve, the charging valve, the booster pump, and the sampling container connection valve in sequence. Remove the sampling container and attach a label.

[0013] g) If you want to continue sampling from the same device, change the sampling container and repeat steps b) to f);

[0014] h) Remove the connecting pipes and restore the equipment's charging / discharging valves to their original state.

[0015] This invention also provides a sampling method based on the aforementioned sulfur hexafluoride and its mixed gas sampling device for electrical equipment. When sampling is performed on the electrical equipment, and the gas pressure is higher than 0.2 MPa, a vacuum sampling method is used. The sampling steps are as follows:

[0016] a) Connect the sampling container, vacuum pump, and exhaust gas collection device to the sampling module. When it is necessary to pressurize and store the sampled gas, a booster pump also needs to be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0017] b) Open the sampling valve, inflation valve, sampling container connection valve, and tail gas valve, start the vacuum pump, and evacuate the sampling device and sampling container until the system pressure is below 50Pa.

[0018] c) Close the exhaust valve, stop the vacuum pump, and ensure the sampling system is well sealed;

[0019] d) Open the gas charging / discharging valve of the electrical equipment to fill the sampling device and sampling container with gas inside the electrical equipment, and then quickly close the equipment connection valve and the gas charging / discharging valve of the electrical equipment;

[0020] e) Open the tail gas valve, start the vacuum pump, evacuate the sampling device and sampling container for a set time until the system pressure is below 50Pa, then stop the vacuum pump and close the tail gas valve; when the sample needs to be tested for gas mixture ratio, repeat steps d) to e) once.

[0021] f) When it is not necessary to pressurize and store the sample gas, open the gas charging / discharging valve of the electrical equipment and the equipment connection valve of the sampling device to allow the gas in the electrical equipment to fill the sampling container. The gauge pressure is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0022] g) When it is necessary to pressurize and store the sample gas, open the gas charging / discharging valve of the electrical equipment and the equipment connection valve of the sampling device to allow the gas in the electrical equipment to fill the sampling container. When the pressure on the sampling cylinder gauge is consistent with the pressure of the electrical equipment, turn on the booster pump to pressurize and store the sample in the sampling container to the set sampling pressure; however, prevent the storage pressure from being too high, which may cause the sample to liquefy.

[0023] h) Close the electrical equipment charging / discharging valve and the equipment connection valve, sampling valve, charging valve, booster pump, and sampling container connection valve of the sampling device in sequence. Remove the sampling container and affix a label.

[0024] i) To continue sampling from the same device, change the sampling container and repeat steps b) to h);

[0025] j) Remove the connecting pipes and restore the equipment's charging and discharging valves to their original state.

[0026] This invention also provides a sampling method based on the aforementioned sulfur hexafluoride and its mixed gas sampling device for electrical equipment. When sampling is performed on the electrical equipment, and the gas pressure is not higher than 0.2 MPa, a flushing method is used for sampling. The sampling steps are as follows:

[0027] a) Connect the diaphragm pump, sampling container, vacuum pump, and exhaust gas collection device to the sampling module. When it is necessary to pressurize and store the sampled gas, a booster pump also needs to be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0028] b) Close the tail gas valve, open the charging and discharging valves of the electrical equipment and the equipment connection valve, sampling valve, charging valve and sampling container connection valve of the sampling device, start the diaphragm pump until the gauge pressure of the sampling cylinder is 0.1MPa, then close the equipment connection valve and stop the diaphragm pump; use the tail gas collection device to collect the gas in the sampling device until the gauge pressure of the sampling cylinder is 0.01MPa.

[0029] c) Repeat step b) twice to flush out residual gas in the sampling system. When the sample needs to be tested for gas-mix ratio, multiple flushes are required.

[0030] d) When it is not necessary to pressurize and store the sample, close the tail gas valve, open the equipment connection valve, and turn on the diaphragm pump to fill the sampling container with gas from the equipment. The gauge pressure of the sampling cylinder is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0031] e) When pressurizing and storing samples, close the tail gas valve and the inflation valve, open the equipment connection valve, and start the diaphragm pump to fill the sampling cylinder with gas until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. When the gauge pressure of the sampling cylinder is lower than the working pressure of the booster pump, stop the inflation valve, stop the booster pump, reopen the equipment connection valve, start the diaphragm pump, and fill the sampling cylinder with gas again until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. Repeat the above process until the sampling container reaches the set pressure. However, prevent excessive storage pressure from causing sample liquefaction.

[0032] f) After sampling is completed, close the electrical equipment charging / discharging valve, the equipment connection valve of the sampling device, the diaphragm pump, the gas intake valve, the charging valve, the booster pump, and the sampling container connection valve in sequence. Remove the sampling container and affix a label.

[0033] g) If you want to continue sampling from the same device, change the sampling container and repeat steps b) to f);

[0034] h) Remove the connecting pipes and restore the equipment's charging / discharging valves to their original state.

[0035] This invention also provides a sampling method based on the aforementioned sulfur hexafluoride and its mixed gas sampling device for electrical equipment. When sampling is performed on the electrical equipment, and the gas pressure is not higher than 0.2 MPa, a vacuum sampling method is used. The sampling steps are as follows:

[0036] a) Connect the diaphragm pump, sampling container, vacuum pump, and exhaust gas collection device to the sampling module. When it is necessary to pressurize and store the sampled gas, a booster pump also needs to be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0037] b) Open the sampling valve, inflation valve, sampling container connection valve, and tail gas valve, start the vacuum pump, and evacuate the sampling device and sampling container for a set time until the system pressure is below 50Pa.

[0038] c) Close the exhaust valve, stop the vacuum pump, and ensure the sampling system is well sealed;

[0039] d) Open the electrical equipment charging / discharging valve, start the diaphragm pump until the sampling cylinder gauge pressure is 0.1 MPa, close the equipment connection valve of the sampling device and the electrical equipment charging / discharging valve, and stop the diaphragm pump;

[0040] e) Open the tail gas valve, start the vacuum pump, evacuate the sampling device and sampling container for a set time until the system pressure is below 50Pa, then stop the vacuum pump and close the tail gas valve; when the sample needs to be tested for gas mixture ratio, repeat steps d) to e) once.

[0041] f) When it is not necessary to pressurize and store the sample, open the gas charging / discharging valve of the electrical equipment and the equipment connection valve of the sampling device, and turn on the diaphragm pump to allow the gas in the equipment to fill the sampling container. The gauge pressure of the sampling cylinder is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0042] g) When pressurizing and storing samples, close the inflation valve, open the equipment connection valve, and start the diaphragm pump to fill the sampling cylinder with gas until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. When the gauge pressure of the sampling cylinder is lower than the working pressure of the booster pump, close the inflation valve, stop the booster pump, reopen the equipment connection valve, start the diaphragm pump, and fill the sampling cylinder with gas again until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. Repeat the above process until the sampling container reaches the set pressure. However, prevent excessive storage pressure from causing sample liquefaction.

[0043] h) After sampling is completed, close the electrical equipment charging / discharging valve and the equipment connection valve, sampling valve, charging valve, and sampling container connection valve of the sampling device in sequence, remove the sampling container, and affix a label;

[0044] i) To continue sampling from the same device, change the sampling container and repeat steps b) to h);

[0045] j) Remove the connecting pipes and restore the equipment's charging and discharging valves to their original state.

[0046] Compared with existing technologies, the present invention has the following beneficial effects: Through the structural design and coordinated operation of the equipment connection module, sampling module, gas filling module, and vacuuming module, combined with the sampling method provided by the present invention, the accuracy and reliability of sampling sulfur hexafluoride gas or sulfur hexafluoride mixed insulating gas can be improved. It is applicable to cylinders and storage tanks containing sulfur hexafluoride gas or sulfur hexafluoride mixed insulating gas (SF6 / N2, SF6 / CF4, etc.), and also applicable to electrical equipment using sulfur hexafluoride or sulfur hexafluoride mixed insulating gas, such as circuit breakers, transformers, instrument transformers, and combined electrical appliances. Therefore, the present invention has strong practicality and broad application prospects. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the sampling device structure according to an embodiment of the present invention.

[0048] In the diagram: 1. Electrical equipment or gas cylinder / storage tank; 2. Sampling cylinder; 3. Sampling container; 4. Tail gas collection device; 5. Pressure gauge; 6. Diaphragm pump; 7. Booster pump; 8. Vacuum pump; 9. Equipment connection valve; 10. Sampling valve; 11. Inflation valve; 12. Sampling container connection valve; 13. Tail gas valve; 14. Tail gas collection device connection valve. Detailed Implementation

[0049] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0050] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0051] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0052] like Figure 1 As shown, this embodiment provides a sampling device for sulfur hexafluoride and its mixed gases for electrical equipment, including a device connection module, a sampling module, a gas filling module, and a vacuum module. The device connection module is used to connect to the electrical equipment and collect gas, and mainly consists of a device connection valve 9, a diaphragm pump 6, and corresponding pipelines. The sampling module is used for gas buffering and mainly consists of a sampling cylinder 2, a pressure detection unit 5, a sampling valve 10, a gas filling valve 11, a tail gas valve 13, and corresponding pipelines. The gas filling module is used to fill the sampling container with gas and mainly consists of a booster pump 7, a sampling container connection valve 12, and corresponding pipelines. The vacuum module is used to perform vacuum treatment on the sampling device, sampling container, and pipelines, and to collect tail gas, and mainly consists of a vacuum pump 8, a tail gas collection device connection valve 14, and a tail gas collection device 4.

[0053] Specifically, the equipment connection valve, sampling valve, inflation valve, tail gas valve, sampling container connection valve, and tail gas collection device connection valve are all three-way valves. The first port of the equipment connection valve is used to connect to electrical equipment or a gas cylinder / storage tank. The second port of the equipment connection valve is connected to the first port of the sampling valve via a corresponding pipeline. The third port of the equipment connection valve is connected to the third port of the sampling valve via a diaphragm pump and a corresponding pipeline. The second port of the sampling valve is connected to the sampling cylinder via a corresponding pipeline. The first port of the sampling container connection valve is used to connect to the sampling container. The second port of the sampling container connection valve is connected to the first port of the inflation valve via a corresponding pipeline. The third port of the sampling container connection valve is connected to the third port of the inflation valve via a booster pump and a corresponding pipeline. The second port of the inflation valve is connected to the sampling cylinder via a corresponding pipeline. The first port of the exhaust gas collection device connecting valve is connected to the exhaust gas collection device. The second port of the exhaust gas collection device connecting valve is connected to the first port of the exhaust gas valve via a corresponding pipeline. The third port of the exhaust gas collection device connecting valve is connected to the third port of the exhaust gas valve via a vacuum pump and a corresponding pipeline. The second port of the exhaust gas valve is connected to the sampling cylinder via a corresponding pipeline. The pressure detection unit 5 is installed on the sampling cylinder. In this embodiment, the pressure detection unit 5 is a pressure gauge.

[0054] In this embodiment, the sampling cylinder has a volume of not less than 1 L. The diaphragm pump has a gas flow rate of not less than 15 L / min and a maximum output pressure of not less than 0.6 MPa. The booster pump has a gas flow rate of not less than 300 L / min and a maximum output pressure of not less than 1 MPa. The vacuum pump has an anti-backflow protection valve, an ultimate vacuum of 10 Pa, and a pumping rate of not less than 5 m³ / h. The interior of these devices should be made of polytetrafluoroethylene or stainless steel, with the stainless steel inner wall passivated.

[0055] In this embodiment, the gas cylinder should have a pressure reducing device and a three-way valve, good sealing performance, and a passivated inner wall. The maximum gas storage pressure is 4 MPa (20°C), and 1L, 4L, or 8L specifications can be used depending on requirements. The sampling bag should be made of plastic with a self-sealing connector, a plastic thickness of not less than 0.3 mm, and good sealing performance. When the pressure of sulfur hexafluoride gas or sulfur hexafluoride mixture exceeds 0.2 MPa, a stainless steel cylinder should be used for sampling. When the pressure of sulfur hexafluoride gas or sulfur hexafluoride mixture does not exceed 0.2 MPa, either a stainless steel cylinder or a sampling bag can be used for sampling.

[0056] In this embodiment, the piping system consists of pipes, fittings, and valves. The pipes are made of stainless steel or PTFE, with a wall thickness of not less than 1mm, an inner diameter of 2mm~4mm, a smooth and clean inner wall, and self-sealing fittings or valves at the ends. Fittings include self-sealing fittings and equipment connection fittings, made of stainless steel, with good sealing performance, clean, and free from damage and burrs. Valves are made of stainless steel, with PTFE gaskets inside, providing good sealing performance and cleanliness.

[0057] Before sampling, the sampling device should be inspected to ensure it is clean, dry, and leak-proof. Connecting pipelines should be well-sealed and leak-proof. Sampling equipment should have compatible connectors and be connected to the sampling pipeline. The sampling device should be in a sealed state. If sampling is not planned for a short period, it should be filled with high-purity nitrogen. Check the performance and condition of the vacuum pump, diaphragm pump, and booster pump, ensuring they are ready for use. Evacuate the sampling container and maintain it under slight negative pressure.

[0058] For electrical equipment such as circuit breakers, transformers, instrument transformers, and combined electrical appliances, samples should be taken from the equipment's charging and discharging valves, and the sampling device should be connected to the equipment's charging and discharging valves using matching connectors. Gas cylinders or storage tanks should be equipped with pressure reducing devices, which are then connected to the sampling device after pressure reduction.

[0059] This embodiment also provides a sampling method based on the above-mentioned sulfur hexafluoride and its mixed gas sampling device for electrical equipment. For different operating conditions, sampling can be carried out in the following four ways.

[0060] I. Sampling on electrical equipment: When the gas pressure is higher than 0.2 MPa, use the flushing method for sampling. The sampling steps are as follows:

[0061] a) Refer to Figure 1 Connect the sampling container, exhaust gas collection device, and sampling module. When pressurizing and storing the sampled gas is required, a booster pump must also be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0062] b) Close the exhaust gas valve, and open the charging / discharging valve of the electrical equipment, as well as the equipment connection valve, sampling valve, charging valve, and sampling container connection valve. Make the gauge pressure of the sampling cylinder greater than 0.1 MPa, close the equipment connection valve, open the exhaust gas valve and the exhaust gas collection device connection valve, and use the exhaust gas collection device to collect the gas in the sampling device until the gauge pressure of the sampling cylinder is 0.01 MPa.

[0063] c) Repeat step b) twice to flush out residual gas in the sampling system. If the sample needs to be tested for gas-mix ratio, flushing is required four times.

[0064] d) When it is not necessary to pressurize and store the sample, close the tail gas valve and open the equipment connection valve to allow the gas in the equipment to fill the sampling container. The gauge pressure of the sampling tube is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0065] e) When pressurization and storage of samples are required, close the exhaust valve and open the equipment connection valve to allow the gas inside the equipment to fill the sampling container. Once the pressure on the sampling cylinder gauge matches the pressure of the electrical equipment, turn on the booster pump to pressurize and store the sample in the sampling container to the set sampling pressure. However, prevent excessive storage pressure from causing sample liquefaction.

[0066] f) After sampling is completed, close the electrical equipment charging / discharging valve, the equipment connection valve of the sampling device, the gas intake valve, the charging valve, the booster pump, and the sampling container connection valve in sequence. Remove the sampling container and affix a label.

[0067] g) If you want to continue sampling from the same device, change the sampling container and repeat steps b) to f).

[0068] h) Remove the connecting pipes and restore the equipment's charging / discharging valves to their original state.

[0069] II. Sampling on electrical equipment: When the gas pressure is higher than 0.2 MPa, use the vacuum method for sampling. The sampling steps are as follows:

[0070] a) Refer to Figure 1 Connect the sampling container, vacuum pump, and exhaust gas collection device to the sampling module. When pressurizing and storing the sampled gas is required, a booster pump must also be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0071] b) Open the sampling valve, inflation valve, sampling container connection valve, and exhaust valve, start the vacuum pump, and evacuate the sampling device and sampling container until the system pressure is below 50Pa.

[0072] c) Close the exhaust valve, stop the vacuum pump, observe the vacuum pump gauge reading, and ensure that the sampling system is well sealed.

[0073] d) Open the gas charging / discharging valve of the electrical equipment to fill the sampling device and sampling container with gas inside the electrical equipment, and then quickly close the equipment connection valve and the gas charging / discharging valve of the electrical equipment.

[0074] e) Open the exhaust valve, start the vacuum pump, and evacuate the sampling device and sampling container for 2 to 5 minutes until the system pressure is below 50 Pa. Then, stop the vacuum pump and close the exhaust valve. If the sample needs to be tested for gas-liquid ratio, repeat steps d) to e) once.

[0075] f) When it is not necessary to pressurize and store the sample gas, open the gas charging / discharging valve of the electrical equipment and the equipment connection valve of the sampling device to allow the gas in the electrical equipment to fill the sampling container. The gauge pressure is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0076] g) When pressurizing and storing sample gas is required, open the gas charging / discharging valve of the electrical equipment and the equipment connection valve of the sampling device to allow the gas inside the electrical equipment to fill the sampling container. Once the pressure on the sampling cylinder gauge is consistent with the pressure of the electrical equipment, turn on the booster pump to pressurize and store the sample in the sampling container to the set sampling pressure. However, prevent excessive storage pressure from causing sample liquefaction.

[0077] h) Close the electrical equipment charging / discharging valve and the equipment connection valve, sampling valve, charging valve, booster pump, and sampling container connection valve of the sampling device in sequence. Remove the sampling container and affix a label.

[0078] i) If you want to continue sampling from the same device, change the sampling container and repeat steps b) to h).

[0079] j) Remove the connecting pipes and restore the equipment's charging and discharging valves to their original state.

[0080] III. When sampling electrical equipment, if the gas pressure is not higher than 0.2 MPa, use the flushing method for sampling. The sampling steps are as follows:

[0081] a) Refer to Figure 1 Connect the diaphragm pump, sampling container, vacuum pump, and exhaust gas collection device to the sampling module. When pressurization and storage of the sampled gas are required, a booster pump must also be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0082] b) Close the exhaust gas valve, open the charging / discharging valve of the electrical equipment, as well as the equipment connection valve, sampling valve, charging valve, and sampling container connection valve of the sampling device. Start the diaphragm pump until the gauge pressure of the sampling cylinder reaches 0.1 MPa, then close the equipment connection valve and stop the diaphragm pump. Use the exhaust gas collection device to collect the gas in the sampling device until the gauge pressure of the sampling cylinder reaches 0.01 MPa.

[0083] c) Repeat step b) twice to flush out residual gas in the sampling system. If the sample needs to be tested for gas-mix ratio, flushing is required four times.

[0084] d) When it is not necessary to pressurize and store the sample, close the tail gas valve, open the equipment connection valve, and turn on the diaphragm pump to fill the sampling container with gas from the equipment. The gauge pressure of the sampling tube is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0085] e) When pressurizing and storing samples, close the exhaust valve and the inflation valve, open the equipment connection valve, and start the diaphragm pump. Allow the gas inside the equipment to fill the sampling cylinder until the gauge pressure reaches the rated supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. When the gauge pressure of the sampling cylinder is lower than the working pressure of the booster pump, stop the inflation valve, stop the booster pump, reopen the equipment connection valve, start the diaphragm pump, and allow the gas inside the equipment to fill the sampling cylinder again until the gauge pressure reaches the rated supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. Repeat the above process until the sampling container reaches the set pressure. However, prevent excessive storage pressure from causing sample liquefaction.

[0086] f) After sampling is completed, close the electrical equipment charging / discharging valve, the equipment connection valve of the sampling device, the diaphragm pump, the gas intake valve, the charging valve, the booster pump, and the sampling container connection valve in sequence. Remove the sampling container and affix a label.

[0087] g) If you want to continue sampling from the same device, change the sampling container and repeat steps b) to f).

[0088] h) Remove the connecting pipes and restore the equipment's charging / discharging valves to their original state.

[0089] IV. When sampling electrical equipment, if the gas pressure is not higher than 0.2 MPa, use the vacuum method for sampling. The sampling steps are as follows:

[0090] a) Refer to Figure 1 Connect the diaphragm pump, sampling container, vacuum pump, and exhaust gas collection device to the sampling module. When pressurization and storage of the sampled gas are required, a booster pump must also be connected. Connect the sampling container to the charging / discharging port of the electrical equipment using the sampling pipeline.

[0091] b) Open the sampling valve, inflation valve, sampling container connection valve, and exhaust valve, start the vacuum pump, and evacuate the sampling device and sampling container for 2 to 5 minutes until the system pressure is below 50 Pa.

[0092] c) Close the exhaust valve, stop the vacuum pump, observe the vacuum pump gauge reading, and ensure that the sampling system is well sealed.

[0093] d) Open the electrical equipment charging / discharging valve, start the diaphragm pump until the sampling cylinder gauge pressure is 0.1 MPa, close the equipment connection valve of the sampling device and the electrical equipment charging / discharging valve, and stop the diaphragm pump.

[0094] e) Open the exhaust valve, start the vacuum pump, and evacuate the sampling device and sampling container for 2 to 5 minutes until the system pressure is below 50 Pa. Then, stop the vacuum pump and close the exhaust valve. If the sample needs to be tested for gas-liquid ratio, repeat steps d) to e) once.

[0095] f) When it is not necessary to pressurize and store the sample, open the gas charging / discharging valve of the electrical equipment and the equipment connection valve of the sampling device, and turn on the diaphragm pump to allow the gas in the equipment to fill the sampling container. The gauge pressure of the sampling cylinder is determined according to the amount of gas used, but it shall not exceed 0.4 MPa.

[0096] g) When pressurizing and storing samples is required, close the inflation valve, open the equipment connection valve, and start the diaphragm pump. Inflate the sampling cylinder with gas until the gauge pressure reaches the rated supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. When the gauge pressure of the sampling cylinder is lower than the working pressure of the booster pump, close the inflation valve, stop the booster pump, reopen the equipment connection valve, start the diaphragm pump, and inflate the sampling cylinder with gas again until the gauge pressure reaches the rated supply pressure of the diaphragm pump. Then, stop the diaphragm pump, close the equipment connection valve, open the inflation valve, and start the booster pump to pressurize and store the sample in the sampling container. Repeat the above process until the sampling container reaches the set pressure. However, prevent excessive storage pressure from causing sample liquefaction.

[0097] h) After sampling is completed, close the electrical equipment charging / discharging valve, as well as the equipment connection valve, sampling valve, charging valve, and sampling container connection valve of the sampling device in sequence. Remove the sampling container and affix a label.

[0098] i) If you want to continue sampling from the same device, change the sampling container and repeat steps b) to h).

[0099] j) Remove the connecting pipes and restore the equipment's charging and discharging valves to their original state.

[0100] When it is inconvenient to move the gas cylinder and the gas consumption is not large, a sampling device can be used to sample the gas in the gas cylinder or gas storage tank. The operation method is the same as sampling in electrical equipment.

[0101] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A sampling device for sulfur hexafluoride and mixed gas thereof used in electrical equipment, characterized by, The device connecting module is used for connecting with the electrical equipment and taking gas, mainly composed of a device connecting valve, a diaphragm pump and corresponding pipelines; the sampling module is used for gas buffering, mainly composed of a sampling cylinder, a pressure detection unit, a sampling valve, a gas filling valve, a tail gas valve and corresponding pipelines; the gas filling module is used for filling the sampling container with gas, mainly composed of a booster pump, a sampling container connecting valve and corresponding pipelines; the vacuum pumping module is used for vacuumizing the sampling cylinder, the sampling container and the pipelines and collecting tail gas, mainly composed of a vacuum pump, a tail gas collecting device connecting valve and a tail gas collecting device; The device connecting valve, the sampling valve, the gas filling valve, the tail gas valve, the sampling container connecting valve and the tail gas collecting device connecting valve are all three-way valves; the first interface of the device connecting valve is used for connecting the electrical equipment or a steel cylinder or a gas storage tank, the second interface of the device connecting valve is connected with the first interface of the sampling valve through corresponding pipelines, the third interface of the device connecting valve is connected with the third interface of the sampling valve through the diaphragm pump and corresponding pipelines, the second interface of the sampling valve is connected with the sampling cylinder through corresponding pipelines; the first interface of the sampling container connecting valve is used for connecting the sampling container, the second interface of the sampling container connecting valve is connected with the first interface of the gas filling valve through corresponding pipelines, the third interface of the sampling container connecting valve is connected with the third interface of the gas filling valve through the booster pump and corresponding pipelines, the second interface of the gas filling valve is connected with the sampling cylinder through corresponding pipelines; the first interface of the tail gas collecting device connecting valve is connected with the tail gas collecting device, the second interface of the tail gas collecting device connecting valve is connected with the first interface of the tail gas valve through corresponding pipelines, the third interface of the tail gas collecting device connecting valve is connected with the third interface of the tail gas valve through the vacuum pump and corresponding pipelines, the second interface of the tail gas valve is connected with the sampling cylinder through corresponding pipelines; the pressure detection unit is installed on the sampling cylinder.

2. The sampling method of the sampling device for sulfur hexafluoride and mixed gas thereof for electrical equipment according to claim 1, characterized by, Sampling is carried out on the electrical equipment, when the gas pressure is higher than 0.2 MPa, the flushing method is used for sampling, and the sampling steps are as follows: a) connecting the sampling container, the tail gas collecting device and the sampling module, when the sampling gas needs to be pressurized and stored, the booster pump also needs to be connected; connecting the sampling container with the gas charging and discharging port of the electrical equipment through the sampling pipeline; b) closing the tail gas valve, opening the gas charging and discharging valve of the electrical equipment and the device connecting valve, the sampling valve, the gas filling valve and the sampling container connecting valve; making the gage pressure of the sampling cylinder greater than 0.1 MPa, closing the device connecting valve, opening the tail gas valve and the tail gas collecting device connecting valve, and collecting the gas in the sampling device to the gage pressure of 0.01 MPa in the sampling cylinder by using the tail gas collecting device; c) repeating the operation of b) for 2 times for flushing the residual gas in the sampling system, when the sample needs to carry out mixed gas ratio detection, it needs to be flushed for multiple times; d) when the sample does not need to be pressurized and stored, closing the tail gas valve and opening the device connecting valve, so that the gas in the device is filled into the sampling container, and the gage pressure of the sampling cylinder is determined according to the amount of gas, but the highest one does not exceed 0.4 MPa. e) When the sample needs to be stored under pressure, close the tail gas valve, open the equipment connection valve, and let the gas in the equipment fill the sampling container. When the sampling cylinder pressure is consistent with the pressure of the electrical equipment, open the pressure pump to store the sample under pressure in the sampling container to the set sampling pressure. However, prevent the sample from liquefying due to excessive storage pressure; f) After sampling, close the electrical equipment charging and discharging valve, the equipment connection valve of the sampling device, and the gas sampling valve, the gas charging valve, the pressure pump, and the sampling container connection valve in turn. Remove the sampling container and attach a label; g) If the same equipment is to be sampled continuously, repeat steps b) to f) after replacing the sampling container; h) Remove the connecting pipeline and restore the original state of the equipment charging and discharging valve.

3. The sampling method of the sampling device for sulfur hexafluoride and mixed gas thereof for electrical equipment according to claim 1, characterized by, When sampling from electrical equipment, if the gas pressure is higher than 0.2 MPa, use the vacuum sampling method. The sampling steps are as follows: a) Connect the sampling container, vacuum pump, and tail gas collection device to the sampling module. When the sampled gas needs to be stored under pressure, a pressure pump is also needed. Use the sampling pipeline to connect the sampling container to the electrical equipment charging and discharging port; b) Open the sampling valve, gas charging valve, sampling container connection valve, and tail gas valve, and start the vacuum pump to vacuum the sampling cylinder and sampling container to a system pressure below 50 Pa; c) Close the tail gas valve and stop the vacuum pump to ensure good sealing of the sampling system; d) Open the electrical equipment charging and discharging valve to fill the sampling cylinder and sampling container with gas from the electrical equipment, then quickly close the equipment connection valve and the electrical equipment charging and discharging valve; e) Open the tail gas valve, start the vacuum pump, and vacuum the sampling cylinder and sampling container for a set time until the system pressure is below 50 Pa. Stop the vacuum pump and close the tail gas valve. When the sampled sample needs to be mixed for detection, repeat steps d) to e) once; f) When the sampled gas does not need to be stored under pressure, open the electrical equipment charging and discharging valve and the equipment connection valve of the sampling device to fill the sampling container with gas from the electrical equipment. Determine the pressure based on the amount of gas used, but the maximum pressure should not exceed 0.4 MPa; g) When the sampled gas needs to be stored under pressure, open the electrical equipment charging and discharging valve and the equipment connection valve of the sampling device to fill the sampling container with gas from the electrical equipment. When the sampling cylinder pressure is consistent with the pressure of the electrical equipment, open the pressure pump to store the sample under pressure in the sampling container to the set sampling pressure. However, prevent the sample from liquefying due to excessive storage pressure; h) Close the electrical equipment charging and discharging valve and the equipment connection valve of the sampling device, the sampling valve, the gas charging valve, the pressure pump, and the sampling container connection valve in turn. Remove the sampling container and attach a label; i) If the same equipment is to be sampled continuously, repeat steps b) to h) after replacing the sampling container; j) Remove the connecting pipeline and restore the original state of the equipment charging and discharging valve.

4. The sampling method of the sampling device for sulfur hexafluoride and mixed gas thereof for electrical equipment according to claim 1, characterized by, When sampling from electrical equipment, if the gas pressure is not higher than 0.2 MPa, use the flushing method for sampling. The sampling steps are as follows: a) Connect the diaphragm pump, sampling container, vacuum pump, and tail gas collection device to the sampling module. When the sampled gas needs to be stored under pressure, a pressure pump is also needed. Use the sampling pipeline to connect the sampling container to the electrical equipment charging and discharging port; b) Open the sampling valve, gas charging valve, sampling container connection valve, and tail gas valve, and start the vacuum pump to vacuum the sampling cylinder and sampling container to a system pressure below 50 Pa; c) Close the tail gas valve and stop the vacuum pump to ensure good sealing of the sampling system; d) Open the electrical equipment charging and discharging valve to fill the sampling cylinder and sampling container with gas from the electrical equipment, then quickly close the equipment connection valve and the electrical equipment charging and discharging valve; e) Open the tail gas valve, start the vacuum pump, and vacuum the sampling cylinder and sampling container for a set time until the system pressure is below 50 Pa. Stop the vacuum pump and close the tail gas valve. When the sampled sample needs to be mixed for detection, repeat steps d) to e) once; f) When the sampled gas does not need to be stored under pressure, open the electrical equipment charging and discharging valve and the equipment connection valve of the sampling device to fill the sampling container with gas from the electrical equipment. Determine the pressure based on the amount of gas used, but the maximum pressure should not exceed 0.4 MPa; g) When the sampled gas needs to be stored under pressure, open the electrical equipment charging and discharging valve and the equipment connection valve of the sampling device to fill the sampling container with gas from the electrical equipment. When the sampling cylinder pressure is consistent with the pressure of the electrical equipment, open the pressure pump to store the sample under pressure in the sampling container to the set sampling pressure. However, prevent the sample from liquefying due to excessive storage pressure; h) Close the electrical equipment charging and discharging valve and the equipment connection valve of the sampling device, the sampling valve, the gas charging valve, the pressure pump, and the sampling container connection valve in turn. Remove the sampling container and attach a label; i) If the same equipment is to be sampled continuously, repeat steps b) to h) after replacing the sampling container; j) Remove the connecting pipeline and restore the original state of the equipment charging and discharging valve. b) Close the tail gas valve, open the gas charging valve of the electrical equipment and the equipment connection valve, sampling valve, gas charging valve and sampling container connection valve of the sampling device, start the diaphragm pump until the sampling cylinder gauge pressure is 0.1 MPa, then close the equipment connection valve and stop the diaphragm pump; collect the gas in the sampling device to the sampling cylinder gauge pressure of 0.01 MPa by using the tail gas collection device; c) Repeat the operation of b) 2 times for flushing the residual gas in the sampling system, and flush multiple times when the sampled sample needs to carry out mixed gas ratio detection; d) When the sample does not need to be stored under pressure, close the tail gas valve, open the equipment connection valve, start the diaphragm pump, and charge the gas in the equipment into the sampling container, and determine the sampling cylinder gauge pressure according to the gas amount, but the highest does not exceed 0.4 MPa; e) When the sample needs to be stored under pressure, close the tail gas valve and the gas charging valve, open the equipment connection valve, start the diaphragm pump, and charge the gas in the equipment into the sampling cylinder until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump, then stop the diaphragm pump, close the equipment connection valve, open the gas charging valve, and start the pressure boosting pump to store the sample under pressure in the sampling container; when the gauge pressure of the sampling cylinder is lower than the working pressure of the pressure boosting pump, close the gas charging, stop the pressure boosting pump, reopen the equipment connection valve, start the diaphragm pump, and charge the gas in the equipment into the sampling cylinder until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump, then stop the diaphragm pump, close the equipment connection valve, open the gas charging valve, and start the pressure boosting pump to store the sample under pressure in the sampling container; repeat the above process until the sampling container reaches the set pressure; but prevent the sample from liquefying due to excessive storage pressure; f) After sampling, sequentially close the electrical equipment gas charging valve, the equipment connection valve of the sampling device, the diaphragm pump, and the gas sampling valve, the gas charging valve, the pressure boosting pump and the sampling container connection valve, remove the sampling container, and attach a label; g) If the same equipment is to be continuously sampled, repeat the steps of b) to f) after replacing the sampling container; h) Remove the connecting pipeline and restore the original state of the equipment gas charging valve.

5. The sampling method of the sampling device for sulfur hexafluoride and mixed gas thereof for electrical equipment according to claim 1, characterized by, When sampling the electrical equipment, when the gas pressure is not higher than 0.2 MPa, the vacuum pumping method is used for sampling, and the sampling steps are as follows: a) Connect the diaphragm pump, sampling container, vacuum pump and tail gas collection device with the sampling module, and also connect the pressure boosting pump when the sampled gas needs to be stored under pressure; connect the sampling container with the electrical equipment gas charging port by using the sampling pipeline; b) Open the sampling valve, gas charging valve, sampling container connection valve, tail gas valve, and start the vacuum pump to pump the sampling cylinder and sampling container to a set time until the system pressure is lower than 50 Pa; c) Close the tail gas valve and stop the vacuum pump to ensure good sealing of the sampling system; d) Open the electrical equipment gas charging valve, start the diaphragm pump until the sampling cylinder gauge pressure is 0.1 MPa, close the equipment connection valve of the sampling device and the electrical equipment gas charging valve, and stop the diaphragm pump; e) Open the tail gas valve, start the vacuum pump to pump the sampling cylinder and sampling container to a set time until the system pressure is lower than 50 Pa, stop the vacuum pump, and close the tail gas valve; when the sampled sample needs to carry out mixed gas ratio detection, repeat steps d) to e) once; f) When the sample is not required to be stored under pressure, open the electrically controlled gas charging and discharging valve, the device connection valve of the sampling device, and start the diaphragm pump to fill the sampling container with gas in the device, and determine the gauge pressure of the sampling cylinder according to the amount of gas required, but the maximum pressure should not exceed 0.4 MPa; g) When the sample is required to be stored under pressure, close the gas charging valve, open the device connection valve, and start the diaphragm pump to fill the sampling cylinder with gas in the device until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump, then stop the diaphragm pump, close the device connection valve, open the gas charging valve, and start the pressure boosting pump to store the sample in the sampling container under pressure; when the gauge pressure of the sampling cylinder is lower than the working pressure of the pressure boosting pump, close the gas charging valve, stop the pressure boosting pump, reopen the device connection valve, and start the diaphragm pump to fill the sampling cylinder with gas in the device until the gauge pressure reaches the rated gas supply pressure of the diaphragm pump, then stop the diaphragm pump, close the device connection valve, open the gas charging valve, and start the pressure boosting pump to store the sample in the sampling container under pressure; repeat the above process until the sampling container reaches the set pressure; but prevent the sample from being liquefied due to excessively high storage pressure; h) After sampling is completed, sequentially close the electrically controlled gas charging and discharging valve, the device connection valve of the sampling device, the sampling valve, the gas charging valve, and the sampling container connection valve, remove the sampling container, and attach a label; i) If the same device is to be continuously sampled, repeat steps b) to h) after replacing the sampling container; j) Remove the connecting pipeline and restore the original state of the device gas charging and discharging valve.

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