A portable sulfur hexafluoride decomposition gas detection device

Abstract

The invention discloses a portable sulfur hexafluoride decomposition gas detection device, comprising a detector and a decomposition tank, wherein a heat insulation board is arranged in the decomposition tank, the heat insulation board divides the decomposition tank into an upper cavity and a lower cavity, a heating rod is arranged at the center of the upper cavity, a plurality of cylindrical heat conductive films are arranged in the upper cavity, the heat conductive films divide the decomposition tank into a plurality of concentric experimental cavities, a gas sensitive sensor of the detector is arranged in the experimental cavity, a spiral tube is embedded in the heat insulation board at the bottom of the experimental cavity, and the cross section of the spiral tube is 0.2-1 mm 2 The spacing between adjacent airflow channels in the spiral tube is 0.5 to 1.5 cm, the length of the spiral tube is 100 to 300 cm, each experimental cavity is connected to the lower cavity through the spiral tube, a temperature control device is provided in the lower cavity, an airflow detection device is provided on the spiral tube connected to the outermost experimental cavity of the lower cavity, and the temperature control device is used to adjust the temperature in the lower cavity. The present invention prevents other gases from entering the experimental cavity, and the pressure between different experimental cavities is dynamically balanced, so as to prevent the isolation membrane from being damaged due to the pressure difference between the isolation membranes.

Description

Technical Field

[0001] The invention relates to the technical field of sulfur hexafluoride decomposition detection, and in particular to a portable sulfur hexafluoride decomposition gas detection device. Background Art

[0002] After being heated, sulfur hexafluoride decomposes into sulfur dioxide, carbon tetrafluoride and other gases. Analysis of the decomposition products of sulfur hexafluoride around the heat source can provide experimental data for studying how to prevent sulfur hexafluoride from decomposing under heat. The decomposition detection equipment disclosed in the prior art uses an isolation membrane to divide the decomposition tank into several concentric ring experimental chambers, and then connects the different experimental chambers to the cylinder through an air pipe. The cylinder is provided with a piston to divide the cylinder into different chambers, and the chambers are connected to the experimental chambers one by one. The air pressure is adjusted by the movement of the piston to make the air pressure in different experimental chambers equal. However, due to the friction resistance of the movement of the piston, the air pressure on both sides needs to reach a certain difference before the adjustment can be triggered, which will cause the isolation membrane to be damaged due to the pressure difference. At the same time, due to the change in pressure due to the movement of the piston, the gas in the cylinder will flow back into the experimental chamber, thereby changing the gas content in the experimental chamber, resulting in inaccurate experimental data. Summary of the invention

[0003] In view of the above-mentioned prior art, the present invention provides a portable sulfur hexafluoride decomposition gas detection device to prevent other gases from entering the experimental chamber, dynamically balance the pressure between different experimental chambers, and avoid damage to the isolation membrane due to the pressure difference between the isolation membranes.

[0004] The technical solution of the present invention is achieved in this way:

[0005] A portable sulfur hexafluoride decomposition gas detection device comprises a detector and a decomposition tank, wherein an insulation board is arranged in the decomposition tank, the insulation board divides the decomposition tank into an upper cavity and a lower cavity, a heating rod is arranged at the center of the upper cavity, a plurality of cylindrical heat-conductive films are arranged in the upper cavity, the heat-conductive films divide the decomposition tank into a plurality of concentric experimental cavities, a gas sensor of the detector is arranged in the experimental cavity, a spiral tube is embedded in the insulation board at the bottom of the experimental cavity, the cross section of the spiral tube is 0.2-1 mm2, the spiral tube is a plane spiral tube, the spacing between adjacent airflow channels in the spiral tube is 0.5-1.5 cm, the length of the spiral tube is 100-300 cm, each of the experimental cavities is connected to the lower cavity through the spiral tube, a temperature control device is arranged in the lower cavity, an airflow detection device is arranged on the spiral tube connected to the experimental cavity at the outermost side of the lower cavity, and the temperature control device is used to adjust the temperature in the lower cavity.

[0006] Furthermore, the temperature control device includes an electric heating wire, a sealing plate and a semiconductor cooling plate. The electric heating wire is arranged in the lower cavity. The side wall of the lower cavity is provided with a through hole. The sealing plate is provided on the inner side of the through hole. The semiconductor cooling plate is provided in the through hole. The cold end of the semiconductor cooling plate is in contact with the sealing plate.

[0007] Furthermore, the semiconductor cooling sheet and the heating wire are connected to the controller signal, and the controller is connected to the airflow detection device signal.

[0008] Furthermore, the gas sensor includes a shell and a sensing electrode, a heating electrode and a gas-sensitive material coating area arranged in the shell, the heating electrode is surrounded by the outer periphery of the sensing electrode, a C-shaped conductive area is provided at the end of one of the sensing electrodes, and the other sensing electrode extends into the middle of the C-shaped conductive area, the gas-sensitive material coating area is provided in the C-shaped conductive area, and the two sensing electrodes are interconnected through the gas-sensitive material coating area.

[0009] Furthermore, the gas-sensitive material coating area uses carbon nanotubes doped with a mixed metal of platinum and palladium.

[0010] Furthermore, a temperature sensor, an air pressure sensor and a humidity sensor are provided in the experimental chamber, and the temperature sensor, the air pressure sensor and the humidity sensor are connected to the controller signal, and the controller is connected to the display unit signal.

[0011] Further, the airflow detection device includes an arc tube, a light ball and a photoelectric sensor. The arc tube is connected to the spiral tube, the middle part of the arc tube is bent downward, the two ends of the arc tube are trumpet-shaped openings, the trumpet-shaped openings are provided with limiters, the limiters are used to limit the light ball from moving to the spiral tube, the two ends of the arc tube are provided with the photoelectric sensors, the light ball is sensed by the transport photoelectric sensor when it moves to the two ends of the arc tube, the photoelectric sensor is connected to the controller signal, and the controller is connected to the temperature control device signal. .

[0012] Furthermore, the limiting member is a limiting protrusion, and the limiting protrusion is fixed to the side wall of the bell mouth.

[0013] The beneficial effect of the present invention is that when the temperature rises slowly, the present invention can achieve "zero pressure difference" on both sides of the thermally conductive diaphragm, greatly improving the selection range of the thermally conductive diaphragm, and the use of ultra-thin thermally conductive diaphragms is not easy to break. Under ideal conditions, the present invention can prevent the introduction of gases from other experimental cavities and gases in the lower cavity into each experimental cavity in the experiment, and detect the SF6 decomposition products in each experimental cavity, which can effectively analyze the decomposition of SF6 and provide data for studying the decomposition of SF6. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only preferred embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 This is a structural schematic diagram of a portable sulfur hexafluoride decomposition gas detection device of the present invention;

[0016] Figure 2 It is a schematic diagram of the structure of the gas sensor of the present invention;

[0017] Figure 3 It is a structural schematic diagram of the spiral tube of the present invention;

[0018] Figure 4 It is a structural schematic diagram of the spiral tube and the airflow detection device of the present invention;

[0019] Figure 5 It is a structural schematic diagram of the airflow detection device of the present invention;

[0020] In the figure, 1 is a detector, 2 is a decomposition tank, 3 is an insulation board, 4 is an upper cavity, 5 is a lower cavity, 6 is a heating rod, 7 is a thermally conductive film, 8 is an experimental cavity, 9 is a gas sensor, 10 is a spiral tube, 11 is a temperature control device, 12 is an airflow detection device, 13 is an electric heating wire, 14 is a sealing plate, 15 is a semiconductor refrigeration plate, 16 is a through hole, 17 is a shell, 18 is a sensing electrode, 19 is a heating electrode, 20 is a gas-sensitive material coating area, 21 is a C-shaped conductive area, 22 is a temperature sensor, 23 is an air pressure sensor, 24 is a humidity sensor, 25 is an arc tube, 26 is a lightweight ball, 27 is a photoelectric sensor, 28 is a trumpet-shaped opening, 29 is a limiter, 30 is a controller, and 31 is a spacing between adjacent airflow channels in the spiral tube. DETAILED DESCRIPTION

[0021] In order to better understand the technical content of the present invention, specific embodiments are provided below, and the present invention is further described in conjunction with the accompanying drawings.

[0022] See also Figures 1 to 5A portable sulfur hexafluoride decomposition gas detection device comprises a detector 1 and a decomposition tank 2, wherein the decomposition tank 2 is provided with an insulation board 3, wherein the insulation board 3 divides the decomposition tank 2 into an upper cavity 4 and a lower cavity 5, wherein a heating rod 6 is provided at the center of the upper cavity 4, wherein a plurality of cylindrical heat-conducting films 7 are provided in the upper cavity 4, wherein the heat-conducting films 7 divide the decomposition tank 2 into a plurality of concentric experimental cavities 8, wherein a gas sensor 9 of the detector 1 is provided in the experimental cavity, wherein the insulation board 3 at the bottom of the experimental cavity 8 A spiral tube 10 is embedded therein, the cross-section of the spiral tube 10 is 0.2 to 1 mm2, the spiral tube 10 is a planar spiral tube 10, the spacing 31 between adjacent airflow channels in the spiral tube 10 is 0.5 to 1.5 cm, the length of the spiral tube 10 is 100 to 300 cm, each of the experimental chambers 8 is connected to the lower chamber 5 through the spiral tube 10, and a temperature control device 11 and an airflow detection device are provided in the lower chamber 5, and the temperature control device 11 is used to adjust the temperature in the lower chamber 5.

[0023] An insulation board 3 is provided in the decomposition tank 2, and the insulation board 3 divides the decomposition tank 2 into an upper cavity 4 and a lower cavity 5. A heating rod 6 is provided at the center of the upper cavity 4. When performing a decomposition experiment, SF6 gas is filled into the decomposition tank 2, and the SF6 gas in the decomposition tank 2 is heated by the heating rod 6, so that a temperature field is formed around the heating rod 6. A plurality of cylindrical heat-conducting films 7 are provided in the upper cavity 4 of the decomposition tank 2, and the heat-conducting films 7 divide the decomposition tank 2 into a plurality of concentric experimental cavities 8. The heat-conducting films 7 divide different distances from the heating rod 6 into different experimental cavities 8. The SF6 gas in different experimental cavities 8 cannot flow freely, and the heat-conducting films 7 play the role of gas isolation but not heat insulation. The SF6 in the experimental cavity 8 is decomposed under heating, and a gas sensor 9 is provided in the heating cavity. The decomposition products in the experimental cavity 8 at different distances from the heating rod 6 are detected by the gas sensor 9, so as to provide data for studying the decomposition of SF6. During the heating process, the temperature of the experimental cavity 8 closer to the center is higher, and its gas pressure will increase as the temperature rises. The bottom of the experimental cavity is connected to the lower cavity 5 through the spiral tube 10. Therefore, the SF6 in the experimental cavity 8 will flow from the spiral tube 10 to the lower cavity 5, releasing the pressure of the gas in the experimental cavity 8. Finally, the gas pressure in each experimental cavity 8 is the same, avoiding the pressure difference between adjacent experimental cavities 8 and causing the thermal conductive diaphragm to rupture.

[0024] During the pressure release process, the gas can flow directly through the air flow channel in the spiral tube 10. Since there is no piston or other components that block the flow of gas, there is no need to push any components to move when the gas flows, thereby avoiding the pressure difference caused by the movement being blocked due to friction and inertia. When the temperature rises slowly, the present invention can achieve "zero pressure difference" on both sides of the thermal conductive diaphragm, greatly improving the selection range of the thermal conductive diaphragm, and the use of an ultra-thin thermal conductive diaphragm is not easy to break. Since there is no need to set up a piston or other components that block the flow of gas, the structure of the device is simplified, the cost of the device is reduced, and it is easier to promote and use. The present invention sets a temperature control device in the lower cavity 5, and adjusts the air pressure of the lower cavity 5 by controlling the temperature in the lower cavity 5. During the decompression process, SF6 flows from the spiral tube 10 to the lower cavity 5. Since the spiral tube 10 is coiled in the insulation board 3, the length of the airflow channel in the spiral tube 10 is increased. The length of the spiral tube 10 can reach 100cm to 300cm. The inner diameter of the spiral tube 10 is only 0.2 to 2mm. Therefore, it is difficult for the heat in the upper cavity 4 to transfer heat from the spiral tube 10 to the lower cavity 5 through heat transfer. The spiral tube 10 has the effect of ventilation without heat conduction, thereby effectively avoiding the heat loss in the upper cavity 4. The spiral tube 10 is a flat spiral tube 10, which can be well embedded in the insulation board 3. The spacing 31 between adjacent airflow channels in the spiral tube 10 is 0.5 to 1.5cm, which can reduce the direct heat transfer from adjacent pipes and improve the insulation effect. During the decompression process, the hot gas in the innermost experimental chamber 8 will enter the lower chamber 5. When the amount of gas from the innermost experimental chamber 8 entering the lower chamber 5 is large, causing the gas to flow back into the outermost experimental chamber 8, the airflow sensor can detect the flow direction of the gas, thereby controlling the temperature regulating device to adjust the temperature in the experimental chamber 8, thereby adjusting the air pressure in the experimental chamber 8, causing the air pressure in the lower chamber 5 to rise synchronously with the air pressure in the outermost experimental chamber 8, thereby preventing the airflow in the lower chamber 5 from flowing back into the experimental chamber 8. Under ideal conditions, the present invention can prevent the introduction of gases from other experimental chambers 8 or gases from the lower chamber 5 into each experimental chamber 8 in the experiment, and detect the SF6 decomposition products in each experimental chamber 8, which can effectively analyze the decomposition of SF6 and provide data for studying the decomposition of SF6.

[0025] Specifically, the temperature control device 11 includes a heating wire 13, a sealing plate 14 and a semiconductor cooling sheet 15. The heating wire 13 is arranged in the lower cavity 5. The side wall of the lower cavity 5 is provided with a through hole 16. The sealing plate 14 is arranged inside the through hole 16. The semiconductor cooling sheet 15 is arranged in the through hole 16. The cold end of the semiconductor cooling sheet 15 is in contact with the sealing plate 14. When the temperature in the lower cavity 5 is too low, the gas in the outermost experimental cavity 8 flows toward the lower cavity 5, and the heating wire 13 is energized to heat the gas in the lower cavity 5 by using the heating wire 13, thereby increasing the gas pressure in the lower cavity 5 and reducing the gas flow in the outermost experimental cavity 8. When the temperature in the lower cavity 5 is too high, causing the gas in the lower cavity 5 to flow toward the outermost experimental cavity 8, the semiconductor cooling sheet 15 is energized, and the cold end of the semiconductor cooling sheet 15 contacts the sealing plate 14, which is made of a heat-conducting material. The heat is transferred to the semiconductor cooling sheet 15 through the sealing plate 14, and finally discharged from the hot end of the semiconductor cooling sheet 15, thereby reducing the temperature of the lower cavity, reducing the air pressure in the lower cavity 5, and preventing the gas in the lower cavity 5 from flowing toward the experimental cavity 8. The sealing plate 14 seals the through hole 16, improves the airtightness of the lower cavity 5, and prevents gas leakage in the lower cavity 5.

[0026] Specifically, the semiconductor cooling sheet 15 and the electric heating wire 13 are connected to the controller 30 by signals, and the controller 30 is connected to the airflow detection device by signals. The controller 30 controls the electric heating wire 13 and the semiconductor cooling sheet 15 to work.

[0027] Specifically, the gas sensor 9 includes a shell 17 and a sensing electrode 18, a heating electrode 19 and a gas-sensitive material coating area 20 arranged in the shell 17. The outer periphery of the sensing electrode 18 is surrounded by the heating electrode 19. A C-shaped conductive area 21 is provided at the end of one of the sensing electrodes 18, and the other sensing electrode 18 extends into the middle of the C-shaped conductive area 21. The gas-sensitive material coating area 20 is provided in the C-shaped conductive area 21. The two sensing electrodes 18 are interconnected through the gas-sensitive material coating area 20. The heating electrode 19 is started and heated to 150 degrees Celsius for 10 minutes to restore the gas-sensitive ability of the sensor. A C-shaped conductive area 21 is provided at the end of one of the sensing electrodes 18, and the other sensing electrode 18 extends into the middle of the C-shaped conductive area 21. A gas-sensitive material coating area 20 with a large coverage area can be provided in the C-shaped conductive area 21. When the gas sensor 9 performs detection, the resistance value of the gas-sensitive material coating area 20 changes, thereby affecting the current change of the sensing electrode 18, thereby detecting the gas.

[0028] Specifically, the gas-sensitive material coating area 20 uses carbon nanotubes doped with platinum-palladium mixed metals. When this material comes into contact with sulfur hexafluoride decomposition gas, such as sulfur dioxide, carbon tetrafluoride and other gases, the resistance property will change, and the gas can be detected by this property.

[0029] Specifically, a temperature sensor 22, an air pressure sensor 23 and a humidity sensor 24 are provided in the experimental chamber 8, and the temperature sensor 22, the air pressure sensor 23 and the humidity sensor 24 are connected to the controller 30 by signal, and the controller 30 is connected to the display unit by signal. The temperature, air pressure and humidity values ​​in the experimental chamber 8 are detected by setting the temperature sensor 22, the air pressure sensor 23 and the humidity sensor 24.

[0030] Specifically, the airflow detection device 12 includes an arc tube 25, a light ball 26 and a photoelectric sensor 27. The arc tube 25 is connected to the spiral tube 10. The middle part of the arc tube 25 is bent downward. The two ends of the arc tube 25 are trumpet-shaped openings 28. The trumpet-shaped openings 28 are provided with stoppers 29. The stoppers 29 are used to limit the movement of the light ball 26 to the spiral tube 10. The two ends of the arc tube 25 are provided with the photoelectric sensors 27. When the light ball 26 moves to the two ends of the arc tube 25, it is sensed by the transport photoelectric sensors 27. The photoelectric sensors 27 are connected to the controller 30 by signal, and the controller 30 is connected to the temperature control device 11 by signal. In a natural state, the light ball 26 falls to the bottom of the downward bend of the arc tube 25 under the action of gravity, and the light ball 26 does not block the light path of the photoelectric sensor 27. When there is gas flowing in the spiral tube 10, the gas pushes the light ball 26 to move to one end when passing through the arc tube 25, and the light ball 26 stops moving after moving to the end of the arc tube 25. The end of the arc tube 25 is trumpet-shaped, and the diameter gradually increases in the direction away from the center of the arc tube 25. After the light ball 26 moves to the trumpet-shaped opening position, the gas can flow in the arc tube 25, ensuring the normal flow of the gas in the arc tube 25. At the same time, due to the driving effect of the airflow, the light ball 26 moves to one end of the arc tube 25, and the light ball 26 blocks the light path of the photoelectric sensor 27, so that it is collected by the photoelectric sensor 27. When the gas flows to the left, the light ball 26 on the left blocks the light path of the photoelectric sensor 27 on the left, and when the gas flows to the right, the light ball 26 on the right blocks the light path of the photoelectric sensor 27 on the right. The photoelectric sensor 27 transmits the collected signal to the controller 30, and the controller 30 controls the temperature control device 11 to reduce or increase the temperature of the lower cavity 5 according to the direction of the airflow, reducing the flow of gas to the right. The lightweight ball 26 can be made of lightweight materials such as foam. The lightweight ball 26 has a small weight. In the case of small diameter and micro airflow, the airflow sensor can also detect the direction of the airflow. When the air pressure of the lower cavity 5 and the experimental cavity 8 is dynamically balanced, the temperature of the lower cavity 5 can be controlled and the gas flow between the experimental cavity 8 and the lower cavity 5 can be reduced.

[0031] Specifically, the limiting member 29 is a limiting protrusion fixed to the side wall of the bell mouth. When the light ball 26 moves to the position of the limiting protrusion, the light ball 26 is blocked by the limiting protrusion to prevent the light ball 26 from moving to the interface between the spiral tube 10 and the arc tube 25 and blocking the airflow channel.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A portable sulfur hexafluoride decomposition gas detection device, characterized in that: The invention comprises a detector and a decomposition tank, wherein an insulating plate is arranged in the decomposition tank, the insulating plate divides the decomposition tank into an upper cavity and a lower cavity, a heating rod is arranged at the center of the upper cavity, a plurality of cylindrical heat-conductive films are arranged in the upper cavity, the heat-conductive films divide the decomposition tank into a plurality of concentric experimental cavities, a gas sensor of the detector is arranged in the experimental cavity, a spiral tube is embedded in the insulating plate at the bottom of the experimental cavity, and the cross section of the spiral tube is 0.2-1 mm 2 The spiral tube is a plane spiral tube, the spacing between adjacent airflow channels in the spiral tube is 0.5~1.5cm, the length of the spiral tube is 100~300cm, each of the experimental chambers is connected to the lower chamber through the spiral tube, a temperature control device is provided in the lower chamber, and an airflow detection device is provided on the spiral tube connected to the experimental chamber at the outermost side of the lower chamber, and the temperature control device is used to adjust the temperature in the lower chamber; the airflow detection device includes an arc tube, a lightweight ball and a photoelectric sensor, the arc tube is connected in the spiral tube, the middle part of the arc tube is bent downward, the two ends of the arc tube are trumpet-shaped openings, the trumpet-shaped openings are provided with a limiter, the limiter is used to limit the lightweight ball from moving to the spiral tube, the two ends of the arc tube are provided with the photoelectric sensors, and the lightweight ball is sensed by the transport photoelectric sensor when it moves to the two ends of the arc tube, the photoelectric sensor is connected to the controller signal, and the controller is connected to the temperature control device signal.

2. A portable sulfur hexafluoride decomposition gas detection device according to claim 1, characterized in that: The temperature control device includes a heating wire, a sealing plate and a semiconductor cooling sheet. The heating wire is arranged in the lower cavity. The side wall of the lower cavity is provided with a through hole. The sealing plate is arranged inside the through hole. The semiconductor cooling sheet is arranged in the through hole. The cold end of the semiconductor cooling sheet is in contact with the sealing plate.

3. A portable sulfur hexafluoride decomposition gas detection device according to claim 2, characterized in that: The semiconductor cooling sheet and the heating wire are connected to the controller by signal, and the controller is connected to the airflow detection device by signal.

4. A portable sulfur hexafluoride decomposition gas detection device according to claim 1, characterized in that: The gas sensor includes a shell and a sensing electrode, a heating electrode and a gas-sensitive material coating area arranged in the shell, the heating electrode is surrounded by the outer periphery of the sensing electrode, a C-shaped conductive area is provided at the end of one of the sensing electrodes, the other sensing electrode extends into the middle of the C-shaped conductive area, the gas-sensitive material coating area is provided in the C-shaped conductive area, and the two sensing electrodes are interconnected through the gas-sensitive material coating area.

5. A portable sulfur hexafluoride decomposition gas detection device according to claim 4, characterized in that: The gas-sensitive material coating area adopts carbon nanotubes doped with platinum-palladium mixed metal.

6. A portable sulfur hexafluoride decomposition gas detection device according to claim 1, characterized in that: A temperature sensor, an air pressure sensor and a humidity sensor are arranged in the experimental chamber. The temperature sensor, the air pressure sensor and the humidity sensor are connected to the controller by signal, and the controller is connected to the display unit by signal.

7. A portable sulfur hexafluoride decomposition gas detection device according to claim 1, characterized in that: The limiting member is a limiting protrusion, and the limiting protrusion is fixed on the side wall of the trumpet-shaped opening.

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