CN113083046B - Mixed gas preparation device and inflation method - Google Patents
Mixed gas preparation device and inflation method Download PDFInfo
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- CN113083046B CN113083046B CN202110254906.6A CN202110254906A CN113083046B CN 113083046 B CN113083046 B CN 113083046B CN 202110254906 A CN202110254906 A CN 202110254906A CN 113083046 B CN113083046 B CN 113083046B
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- gas
- mixed gas
- control valve
- inflation
- vacuum pump
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/10—Mixing gases with gases
- B01F23/19—Mixing systems, i.e. flow charts or diagrams; Arrangements, e.g. comprising controlling means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D1/00—Pipe-line systems
- F17D1/02—Pipe-line systems for gases or vapours
- F17D1/04—Pipe-line systems for gases or vapours for distribution of gas
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D3/00—Arrangements for supervising or controlling working operations
- F17D3/01—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of a product
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Gas-Insulated Switchgears (AREA)
Abstract
The invention discloses a mixed gas preparation device and an inflation method, which comprise the following steps: the gas charging system comprises a mixed gas charging device, at least one air pressure sensor and at least one temperature sensor, wherein the air pressure sensor and the temperature sensor are both provided with transmission parts; the mixed gas inflator comprises SF6Gas circuit, N2Gas path of inflation, CO2The device comprises an inflation gas circuit, a test cavity, a mixed gas outlet pipeline and a vacuum pump pipeline; through the mode of filling each component gas into the test cavity of vacuum and remixing and controlling each component gas to reach preset partial pressure respectively, the backflow caused by the air pressure of the air bottle can be avoided, the problem that mixed gas with different proportions is complex to manufacture is solved, the accuracy degree of mixing of insulating gas is improved, and the inflation efficiency is improved.
Description
Technical Field
The invention relates to the technical field of gas insulation materials of electrical equipment, in particular to an insulating mixed gas preparation device and an inflation method.
Background
SF6As an insulating and arc extinguishing medium, it has been widely used in electrical equipment such as Gas Insulated Switchgear (GIS). SF is commonly used at present6、N2、CO2Mixed gas for substituting pure SF6Gas as insulating gas, SF6/N2SF in mixed gas6Has better insulation strength when the proportion is less than 30 percent, and can save most SF6The method has high research value. Currently contains 20% SF6SF of6/N2The mixed Gas has been successfully applied to Gas Insulated Transmission Lines (GIL) of the geneva airport in switzerland, if the arc extinguishing performance of the mixed Gas is not considered, in Gas chambers of GIS equipment except for circuit breakers and disconnectors, low SF6Proportional SF6/N2The mixed gas has great potential to replace pure SF6Not only can greatly reduce SF6Can effectively avoid SF6Liquefaction of gases at low temperatures.
At present, a lot of researches report the influence of various factors such as inflation pressure, mixing ratio, electric field unevenness and the like on the insulating property of a gas insulating medium at home and abroad. However, research is currently underway at home and abroadWhen the mixed gas has the insulating property, SF is filled in firstly6Refilling with N2The method (2) has disadvantages of low aeration efficiency and easy contamination of moisture in the air.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the utility model provides a mist preparation facilities and inflation method, can avoid the refluence that arouses because of gas cylinder atmospheric pressure, solve the loaded down with trivial details problem of different ratio mist preparation, improve the accurate degree that insulating gas mixes, improve simultaneously and aerify efficiency.
In order to solve the above technical problem, an embodiment of the present invention provides a mixed gas preparation apparatus, including: the gas charging system comprises a mixed gas charging device, at least one air pressure sensor and at least one temperature sensor, wherein the air pressure sensor and the temperature sensor are both provided with transmission parts;
the mixed gas inflator comprises SF6Inflation gas circuit, N2Gas path of inflation, CO2The device comprises an inflation gas circuit, a test cavity, a mixed gas outlet pipeline and a vacuum pump pipeline;
wherein the test chamber comprises SF6Test chamber, N2Test chamber and CO2Test chamber, said SF6Test chamber, N2Test chamber and CO2The test cavities are connected in sequence through pipelines to form an annular structure; isolation valves are arranged in the pipelines;
the SF6The test cavity is provided with the SF6Gas circuit of said SF6An SF gas path is provided with the pressure sensor and the temperature sensor6Control valve, said N2The test cavity is provided with the N2Inflation gas circuit, N2N with the air pressure sensor and the temperature sensor is arranged on the inflation gas circuit2Control valve, said CO2The test cavity is provided with the CO2Gas circuit of said CO2The inflation gas circuit is provided with CO with the pressure sensor and the temperature sensor2A control valve;
a mixed gas outlet pipeline and a vacuum pump pipeline are further arranged on the test cavity, an outlet control valve with the air pressure sensor is arranged on the mixed gas outlet pipeline, and a vacuum pump pipeline is provided with a vacuum pump control valve;
an air pump is further arranged in the test cavity.
Correspondingly, the embodiment of the invention also provides an inflation method of the mixed gas preparation device, which is suitable for the mixed gas preparation device, and the method comprises the following steps:
mixing SF6Gas cylinder, N2Gas cylinder and CO2Gas cylinders are respectively connected into the SF6Inflation gas circuit, N2Inflation gas path and CO2The air charging path is used for connecting a vacuum pump into the vacuum pump pipeline and closing all valves;
opening the isolation valve and the vacuum pump control valve, starting the vacuum pump to vacuumize, and continuously vacuumizing for 30min until the pressure in the test cavity is reduced to be below 10Pa, so as to ensure that the test cavity and the gas circuit are fully vacuumized;
after the vacuumizing is finished, closing the isolation valve and the vacuum pump control valve in sequence; controlling a control valve on a corresponding inflation gas path to open according to a preset insulating mixed gas component; when the gas pressure sensor and the temperature sensor monitor that each component gas in the test cavity respectively reaches a preset partial pressure, controlling a control valve on the corresponding inflation gas circuit to be closed;
after the control valves on all the inflation gas paths are normally closed, opening the isolation valve and starting the gas pump for 30min to fully mix the component gases;
connecting a required container to the mixed gas outlet pipeline to ensure that the outlet control valve is in a closed state;
and slowly opening the gas outlet control valve, controlling the gas flow rate by adjusting the size of the gas outlet control valve, pressing the mixed gas into a required container by using the pressure difference, and closing the gas outlet control valve when the pressure of the mixed gas reaches a required test gas pressure monitored by a pressure sensor on the mixed gas outlet pipeline.
Preferably, the preset partial pressure is obtained according to the following steps:
and respectively calculating to obtain the preset partial pressure of each component gas through an ideal gas state equation according to the preset pressure of the insulating mixed gas.
According to the mixed gas preparation device and the inflation method provided by the embodiment of the invention, the backflow caused by the air pressure of the air bottle can be avoided by filling the component gases into the vacuum test cavity for remixing and controlling the component gases to respectively reach the preset partial pressure, so that the problem of complicated manufacture of mixed gases with different proportions is solved, the accuracy of mixing the insulating gases is improved, and the inflation efficiency is improved.
Drawings
FIG. 1 is a schematic structural view of a mixed gas preparation apparatus provided by the present invention;
fig. 2 is a schematic flow chart of an inflation method of a mixed gas preparation device according to another embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.
Referring to fig. 1, it is a schematic structural diagram of a mixed gas preparation device provided by the present invention;
the embodiment of the invention provides a mixed gas preparation device, which comprises: the gas charging system comprises a mixed gas charging device, at least one air pressure sensor and at least one temperature sensor, wherein the air pressure sensor and the temperature sensor are both provided with transmission parts; the pressure sensor and the temperature sensor are respectively used for monitoring the pressure and the temperature in the test cavity, and meanwhile, the pressure sensor and the temperature sensor are both provided with transmission parts, so that the temperature and the pressure of the gas in the gas path can be remotely transmitted to the control room through a transmission cable, and the data can be directly read on a computer.
The mixed gas inflator comprises SF6Inflation gas circuit 1, N 22, CO in the inflating gas path2The device comprises an inflation gas path 3, a test cavity 4, a mixed gas outlet pipeline 5 and a vacuum pump pipeline 6; before inflation, the test cavity, the inflation gas path, the gas outlet pipeline and the vacuum pump pipeline are vacuumized by the vacuum pump and then inflated, so that the residual gas in the mixed gas preparation device is ensured not to influence inflation;
wherein the test chamber 4 comprises SF6Test chamber, N2Test chamber and CO2Test chamber, said SF6Test chamber, N2Test chamber and CO2The test cavities are connected in sequence through pipelines to form an annular structure; isolation valves 7 are arranged in the pipelines;
the SF6The test cavity is provided with the SF6Inflation gas circuit 1, SF6The inflation gas circuit 1 is provided with SF with the air pressure sensor and the temperature sensor6Control valve 8, said N2The test cavity is provided with the N2 Inflation gas path 2, N2The inflating air path 2 is provided with N with the air pressure sensor and the temperature sensor2Control valve 9, said CO2The test cavity is provided with the CO2A gas charging path 3, CO2The inflation gas circuit 3 is provided with CO with the air pressure sensor and the temperature sensor2And controlling the valve 10 to ensure that each component gas is filled into the test cavity corresponding to each component gas, and finishing the filling after each component gas reaches the preset partial pressure.
A mixed gas outlet pipeline 5 and a vacuum pump pipeline 6 are further arranged on the test cavity 4, an outlet control valve 11 with the air pressure sensor is arranged on the mixed gas outlet pipeline 5, and a vacuum pump control valve 12 is arranged on the vacuum pump pipeline 6;
an air pump 13 is also arranged in the test cavity. The gas of each component is fully mixed by a gas pump in the test cavity.
Referring to fig. 2, a schematic flow chart of an inflation method of a mixed gas preparation device according to another embodiment of the present invention is shown.
Another embodiment of the present invention provides an aeration method for a mixed gas production apparatus, including:
s1, mixing SF6Gas cylinder, N2Gas cylinder and CO2Gas cylinders are respectively connected into the SF6Inflation gas circuit 1, N2 Inflation gas path 2 and CO2The air charging path 3 is used for connecting a vacuum pump into the vacuum pump pipeline 6 and closing all valves;
s2, opening the isolation valve 7 and the vacuum pump control valve 12, starting the vacuum pump to vacuumize continuously for 30min until the pressure in the test cavity is reduced to be below 10Pa, and ensuring that the test cavity and the gas circuit are fully vacuumized;
s3, after the vacuumizing is finished, closing the isolation valve 7 and the vacuum pump control valve 12 in sequence; controlling a control valve on a corresponding inflation gas circuit to open according to a preset insulating mixed gas component; when the gas pressure sensor and the temperature sensor monitor that each component gas in the test cavity respectively reaches a preset partial pressure, controlling a control valve on the corresponding inflation gas circuit to be closed; specifically, when the predetermined mixed gas component includes SF6While controlling SF6The control valve 8 is opened; when the predetermined mixed gas component includes N2While controlling N2The control valve 9 is opened; when the predetermined mixed gas component includes CO2Control of CO2The control valve 10 is opened; when SF6SF is monitored by a gas pressure sensor and a temperature sensor6Controlling SF when reaching its preset partial pressure6The control valve 8 is closed; when N is present2The air pressure sensor and the temperature sensor monitor N2When the preset partial pressure is reached, controlling N2The control valve 9 is closed; when CO is present2CO is monitored by a gas pressure sensor and a temperature sensor2When the preset partial pressure is reached, controlling CO2The control valve 10 is closed; optionally, the preset partial pressure of each component gas is calculated respectively through an ideal gas state equation based on the values given by the temperature sensor and the gas pressure sensor according to the preset mixed gas pressure.
S4, opening the isolation valve 7 and opening the control valve on the whole inflation gas path after the control valve is normally closedStarting the air pump 13 for 30min to fully mix the component gases; in particular, when SF6 Control valve 8, N2Control valve 9 and CO2After the control valve 10 is normally closed, opening the isolation valve 7 and starting the air pump 13 for 30min to fully mix the component gases;
s5, connecting a required container into the mixed gas outlet pipeline 5 to ensure that the outlet control valve 11 is in a closed state;
s6, slowly opening the gas outlet control valve 11, controlling the gas flow rate by adjusting the size of the gas outlet control valve, pressing the mixed gas into the required container by using the pressure difference, and closing the gas outlet control valve 11 when the pressure sensor on the mixed gas outlet pipe 5 detects that the gas pressure of the mixed gas reaches the required test gas pressure.
According to the mixed gas preparation device and the inflation method provided by the embodiment of the invention, the backflow caused by the air pressure of the air bottle can be avoided by filling the component gases into the vacuum test cavity for remixing and controlling the component gases to respectively reach the preset partial pressure, so that the problem of complicated manufacture of mixed gases with different proportions is solved, the accuracy of mixing the insulating gases is improved, and the inflation efficiency is improved.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.
Claims (3)
1. A mixed gas production apparatus, characterized by comprising: the gas charging system comprises a mixed gas charging device, at least one air pressure sensor and at least one temperature sensor, wherein the air pressure sensor and the temperature sensor are both provided with transmission parts;
the mixed gas inflator comprises SF6Gas circuit, N2Gas-filled gas circuit, CO2The device comprises an inflation gas circuit, a test cavity, a mixed gas outlet pipeline and a vacuum pump pipeline;
wherein, the instituteThe test chamber comprises SF6Test chamber, N2Test chamber and CO2Test chamber, said SF6Test chamber, N2Test chamber and CO2The test cavities are connected in sequence through pipelines to form an annular structure; isolation valves are arranged in the pipelines;
the SF6The test cavity is provided with the SF6Inflation gas circuit of said SF6An SF gas path is provided with the pressure sensor and the temperature sensor6Control valve, said N2The test cavity is provided with the N2Inflation gas circuit, N2N with the air pressure sensor and the temperature sensor is arranged on the inflation gas circuit2Control valve, said CO2The test cavity is provided with the CO2Gas circuit of said CO2The inflation gas circuit is provided with CO with the air pressure sensor and the temperature sensor2A control valve;
a mixed gas outlet pipeline and a vacuum pump pipeline are further arranged on the test cavity, an outlet control valve with the air pressure sensor is arranged on the mixed gas outlet pipeline, and a vacuum pump pipeline is provided with a vacuum pump control valve;
an air pump is further arranged in the test cavity.
2. A method of inflating a mixed gas production apparatus, which is applied to the mixed gas production apparatus according to claim 1, the method comprising:
mixing SF6Gas cylinder, N2Gas cylinder and CO2Gas cylinders are respectively connected into the SF6Inflation gas circuit, N2Inflation gas path and CO2The air charging path is used for connecting a vacuum pump into the vacuum pump pipeline and closing all valves;
opening the isolation valve and the vacuum pump control valve, starting the vacuum pump to vacuumize, and continuously vacuumizing for 30min until the pressure in the test cavity is reduced to be below 10Pa, so as to ensure that the test cavity and the gas circuit are fully vacuumized;
after the vacuumizing is finished, closing the isolation valve and the vacuum pump control valve in sequence; controlling a control valve on a corresponding inflation gas circuit to open according to a preset insulating mixed gas component; when the air pressure sensor and the temperature sensor monitor that each component of gas in the test cavity respectively reaches a preset partial pressure, controlling a control valve on the corresponding inflation gas circuit to close;
after the control valves on all the inflation gas paths are normally closed, opening the isolation valve and starting the gas pump for 30min to fully mix the component gases;
connecting a required container to the mixed gas outlet pipeline to ensure that the outlet control valve is in a closed state;
and slowly opening the gas outlet control valve, controlling the gas flow rate by adjusting the size of the gas outlet control valve, pressing the mixed gas into a required container by using the action of pressure difference, and closing the gas outlet control valve when the pressure sensor on the gas outlet pipeline of the mixed gas monitors that the gas pressure of the mixed gas reaches the required test gas pressure.
3. The method of charging a mixed gas production apparatus according to claim 2, wherein the preset partial pressure is obtained according to the steps of:
and respectively calculating to obtain the preset partial pressure of each component gas through an ideal gas state equation according to the preset pressure of the insulating mixed gas.
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| CN202110254906.6A CN113083046B (en) | 2021-03-09 | 2021-03-09 | Mixed gas preparation device and inflation method |
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| CN202110254906.6A CN113083046B (en) | 2021-03-09 | 2021-03-09 | Mixed gas preparation device and inflation method |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2061744A (en) * | 1979-10-09 | 1981-05-20 | Mitsubishi Petrochemical Co | Gas-mixing device |
| EP0992732A2 (en) * | 1998-10-08 | 2000-04-12 | Messer Griesheim Gmbh | Production of gas mixtures in large quantities |
| CN203458990U (en) * | 2013-08-05 | 2014-03-05 | 河南科益气体工程有限公司 | Multicomponent mixed gas production device |
| CN204412286U (en) * | 2015-01-30 | 2015-06-24 | 安徽工业大学 | A kind of container bottle for Homogeneous phase mixing gas with various |
| CN105817153A (en) * | 2016-05-19 | 2016-08-03 | 江苏大学 | Ternary gas matching and mixing device |
| KR20170055892A (en) * | 2015-11-12 | 2017-05-22 | 두산중공업 주식회사 | static mixer |
| CN206500045U (en) * | 2017-02-15 | 2017-09-19 | 山东银光钰源轻金属精密成型有限公司 | A kind of distributing cabinet for the protective gas cast for smelting furnace |
| CN108970429A (en) * | 2018-06-15 | 2018-12-11 | 盛密科技(上海)有限公司 | A kind of air distributing device and air distributing method of low concentration calibrating gas |
| CN109925900A (en) * | 2016-10-17 | 2019-06-25 | 平高集团有限公司 | A kind of gas mixer |
| CN210186890U (en) * | 2019-05-17 | 2020-03-27 | 西南交通大学 | Gas rapid mixing device and experimental equipment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11471840B2 (en) * | 2018-12-18 | 2022-10-18 | Billups-Rothenberg, Inc. | Gas mixing system |
-
2021
- 2021-03-09 CN CN202110254906.6A patent/CN113083046B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2061744A (en) * | 1979-10-09 | 1981-05-20 | Mitsubishi Petrochemical Co | Gas-mixing device |
| EP0992732A2 (en) * | 1998-10-08 | 2000-04-12 | Messer Griesheim Gmbh | Production of gas mixtures in large quantities |
| CN203458990U (en) * | 2013-08-05 | 2014-03-05 | 河南科益气体工程有限公司 | Multicomponent mixed gas production device |
| CN204412286U (en) * | 2015-01-30 | 2015-06-24 | 安徽工业大学 | A kind of container bottle for Homogeneous phase mixing gas with various |
| KR20170055892A (en) * | 2015-11-12 | 2017-05-22 | 두산중공업 주식회사 | static mixer |
| CN105817153A (en) * | 2016-05-19 | 2016-08-03 | 江苏大学 | Ternary gas matching and mixing device |
| CN109925900A (en) * | 2016-10-17 | 2019-06-25 | 平高集团有限公司 | A kind of gas mixer |
| CN206500045U (en) * | 2017-02-15 | 2017-09-19 | 山东银光钰源轻金属精密成型有限公司 | A kind of distributing cabinet for the protective gas cast for smelting furnace |
| CN108970429A (en) * | 2018-06-15 | 2018-12-11 | 盛密科技(上海)有限公司 | A kind of air distributing device and air distributing method of low concentration calibrating gas |
| CN210186890U (en) * | 2019-05-17 | 2020-03-27 | 西南交通大学 | Gas rapid mixing device and experimental equipment |
Non-Patent Citations (1)
| Title |
|---|
| 《配制混合气体的简单装置及方法》;王智雄等;《机械工人(热加工)》;19920430(第4期);全文 * |
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