CN216499110U - Automatic gas distribution device for mixed gas - Google Patents
Automatic gas distribution device for mixed gas Download PDFInfo
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- CN216499110U CN216499110U CN202122735703.7U CN202122735703U CN216499110U CN 216499110 U CN216499110 U CN 216499110U CN 202122735703 U CN202122735703 U CN 202122735703U CN 216499110 U CN216499110 U CN 216499110U
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Abstract
The utility model relates to an automatic gas distribution device for mixed gas, and belongs to the technical field of electronic mixed gas. The gas distribution device comprises a charging pipeline, a second gas conveying pipeline, a first gas conveying pipeline, a second gas control valve, a first gas control valve, a pressure sensor before a regulating valve, a flowmeter, a pressure sensor after the regulating valve, a charging control valve, a mixed gas container, an electronic balance, a vacuum pump pipeline, a vacuum pump, a vacuum control valve and a temperature sensor. The accuracy of configuring the content of each gas in the mixed gas can be improved by controlling the flow of the gas introduced into the filling pipeline and adjusting the flow of the gas to a set flow according to specific requirements through DCS according to the front and rear pressures of the regulating valve; the gas distribution device can completely realize automatic preparation of mixed gas, and the content of each gas component in the mixed gas is accurately controlled.
Description
Technical Field
The utility model relates to an automatic gas distribution device for mixed gas, and belongs to the technical field of electronic mixed gas.
Background
A large amount of electronic mixed gas is needed in the production of modern semiconductors, Light Emitting Diodes (LEDs), photovoltaics and the like, and the requirements on the purity and the gas distribution accuracy of the electronic mixed gas are very high, so that the requirements on the purity of raw material gas are very high, and higher requirements are provided for gas filling technologies.
In a semiconductor preparation process, in order to ensure the stability and the repeatability of the process, the requirement on the accuracy of the concentration of the electronic mixed gas is high. The preparation of the mixed gas by a weighing method does not need to consider the compression coefficient and the temperature, and the accuracy is higher, so that the preparation of the mixed gas is more common in the preparation of electronic mixed gas; but the configuration operation is complex and the requirement is high. For example, the control of the filling end point of the gas component is critical to the accuracy but difficult, mainly because the flow rate of the gas at the filling end point is uncontrollable, and the current configuration adopts manual operation, so that an operator needs to stare at a weighing scale on the spot to open and close the inflation valve in time, which has a very high requirement on the quality of the operator, and once the manual operation is performed, the filling result deviates from a preset value due to errors, which may cause an immeasurable result.
Disclosure of Invention
In order to overcome the defects in the prior art, the utility model aims to provide an automatic gas distribution device for mixed gas; the problems that the gas filling end point gas flow rate is uncontrollable, the mixed gas preparation precision is low and the manual control has misoperation in the existing mixed gas preparation process are solved.
In order to achieve the purpose of the utility model, the following technical scheme is provided.
The utility model provides an automatic gas distribution device of gas mixture, gas distribution device is including filling dress pipeline, second gas conveying pipeline, first gas conveying pipeline, second gas control valve, first gas control valve, pressure sensor before the governing valve, flowmeter, pressure sensor behind the governing valve, fill dress control valve, gas mixture container, electronic balance, vacuum pump pipeline, vacuum pump, vacuum control valve and temperature sensor.
The electronic balance uses an ultra-high precision electronic scale of comparator grade, and the typical parameter is 150kg +/-0.05 g.
The vacuum degree of the vacuum pump reaches 1 x 10-5Pa, high vacuum, two-stage vacuum pump.
The pressure sensor before the regulating valve and the pressure sensor after the regulating valve are high-precision vacuum pressure sensors, the measuring range is-0.1-40 MPa, and the precision is +/-0.075%.
The front end of the filling pipeline is divided into two branches, one branch is a second gas conveying pipeline, and the other branch is a first gas conveying pipeline; the tail end of the filling pipeline is connected with the mixed gas container; the front pressure sensor of the regulating valve, the flowmeter, the rear pressure sensor of the regulating valve, the vacuum pump pipeline and the filling control valve are sequentially connected between the front end and the tail end of the filling pipeline.
A second gas control valve is arranged on the second gas conveying pipeline, a first gas control valve is arranged on the first gas conveying pipeline, one end of a vacuum pump pipeline is connected with the filling pipeline, the other end of the vacuum pump pipeline is connected with a vacuum pump, and a vacuum control valve is arranged on the vacuum pump pipeline; the mixed gas container is placed on an electronic balance.
The temperature sensors are positioned at the pressure sensor before the regulating valve and the pressure sensor after the regulating valve, and the gas temperature in the filling pipeline is measured together with the pressure sensor before the regulating valve and the pressure sensor after the regulating valve to obtain the front and back accurate pressure of the regulating valve, so that the regulating valve is controlled to realize the accurate control of the gas flow.
The second gas Control valve, the first gas Control valve, the pressure sensor before the regulating valve, the flowmeter, the pressure sensor after the regulating valve, the filling Control valve, the electronic balance, the vacuum pump, the vacuum Control valve and the temperature sensor realize automatic Control through a Distributed Control System (DCS).
Preferably, the second gas control valve, the first gas control valve, the charging control valve and the vacuum control valve are stainless steel pneumatic diaphragm valves.
Preferably the flow meter is a mass flow meter.
Preferably, the second gas conveying pipeline and the first gas conveying pipeline are both provided with a negative pressure sensor and a high pressure sensor, the negative pressure sensor and the high pressure sensor are respectively connected with the DCS, the negative pressure sensor is used for replacing gas, and the high pressure sensor is used for controlling gas intake; the working conditions of all pipelines can be detected through the negative pressure sensor and the positive pressure sensor, and the DCS controls the gas distribution device to stop working when leakage or blockage occurs.
Preferably, the DCS is also connected with an audible and visual alarm.
Preferably, stainless steel 316L electrolytic polishing pipelines are adopted in the filling pipeline, the second gas conveying pipeline, the first gas conveying pipeline and the vacuum pump pipeline.
Preferably the conduit is 1/2 inches or 1/8 inches.
The line between the charge control valve and the mixture reservoir is preferably an 1/8 inch line to reduce the effect of line tension on the accuracy of the symmetry.
Preferably, a DN5O bellows valve is used between the vacuum control valve and the vacuum pump.
The application steps of the automatic gas distribution device for mixed gas are as follows:
(1) and the DCS controls the second gas control valve, the first gas control valve, the filling control valve and the vacuum control valve to be opened and closed, and system inspection is carried out.
(2) The DCS reads the weight of the mixed gas container on the electronic balance.
(3) The method comprises the steps that first gas is introduced into a mixed gas container through a first gas conveying pipeline and a filling pipeline, the opening of a regulating valve is controlled to be the largest by a DCS at first, when the gas is introduced to a certain degree, the opening of the regulating valve is determined by the DCS according to the front pressure and the rear pressure of the regulating valve, the flow of the gas is accurately controlled to reach the set flow of a flowmeter, the first gas slowly enters the mixed gas container, and the control accuracy of the quality of the introduced gas is improved; and after the first gas is filled, the DCS closes the first gas control valve and evacuates the gas in the filling pipeline through the vacuum pump.
(4) Introducing a second gas into the mixed gas container through a second gas conveying pipeline and a filling pipeline, controlling the opening of the regulating valve to be adjusted to the maximum by the DCS at first, and determining the opening of the regulating valve according to the front and rear pressures of the regulating valve when the gas is introduced to a certain degree, so that the gas flow is accurately controlled to reach the set flow of the flowmeter, the gas slowly enters the mixed gas container, and the control precision of the quality of the introduced gas is improved; and after the gas filling is finished, the DCS closes the second gas control valve and evacuates the filling pipeline through the vacuum pump.
When the gas is introduced to a certain degree, the DCS determines the opening degree of the regulating valve according to the front and rear pressures of the regulating valve, so that the specific control method for accurately controlling the gas flow to reach the set flow of the flowmeter is as follows:
when the residual gas introduction amount is less than 20g, the flow rate is set to be less than or equal to 10 g/s;
when the residual gas introduction amount is more than or equal to 20g, the set flow rate is less than or equal to 20g/s when the gas introduction amount reaches 80%, and the set flow rate is less than or equal to 10g/s when the gas introduction amount reaches 90%.
Preferably, before filling, the filling pipeline is subjected to leak detection by adopting a positive and negative pressure maintaining method, and the method comprises the following specific steps:
before preparing mixed gas, respectively adopting a high-negative pressure maintaining method and a negative pressure maintaining method to perform leak detection on a filling pipeline, vacuumizing the filling pipeline by using a vacuum pump until the pressure is less than or equal to 50Pa, judging whether the filling pipeline leaks by using a pressure sensor before an adjusting valve and a pressure sensor after the adjusting valve, then respectively opening a second gas control valve and a first gas control valve, respectively introducing a first gas and a second gas into the filling pipeline, pressurizing until the pressure is more than or equal to 10MPa, judging whether the pipeline leaks by using the pressure sensor before the adjusting valve and the pressure sensor after the adjusting valve, completing leak detection, then closing the second gas control valve and the first gas control valve, vacuumizing the filling pipeline by using the vacuum pump, and removing residual gas.
The device is suitable for the configuration of the electronic mixed gas, wherein the second gas is diluent gas, and the first gas is component gas; the method can also be used for mixed gas with accurately configured content of each gas in other fields, and the types of the first gas and the second gas are determined according to specific requirements.
Advantageous effects
1. The utility model provides an automatic gas distribution device for mixed gas, which controls the flow of gas introduced into a filling pipeline, adjusts the flow to a set flow according to specific requirements by a DCS (distributed control System) according to the pressure before a regulating valve and the pressure after the regulating valve, improves the control precision of the quality of the introduced gas, and can improve the accuracy of configuring the content of each gas in the mixed gas.
2. The utility model provides an automatic gas distribution device for mixed gas, which is detected and controlled by DCS control, can completely realize an automatic allocation process, is accurate in control, and avoids the risk of manual operation errors.
Drawings
Fig. 1 is a schematic structural diagram of an automatic gas distribution device for a mixed gas in embodiment 1.
Fig. 2 is a DCS control schematic diagram of an automatic gas distribution device for mixed gas in embodiment 1.
The system comprises a filling pipeline 1, a second gas conveying pipeline 2, a first gas conveying pipeline 3, a second gas control valve 4, a first gas control valve 5, a pressure sensor before a regulating valve 6, a regulating valve 7, a flow meter 8, a pressure sensor after a regulating valve 9, a filling control valve 10, a mixed gas container 11, an electronic balance 12, a vacuum pump 13 and a vacuum control valve 14
Detailed Description
The utility model will be described in more detail with reference to the following drawings and specific examples, which should not be construed as limiting the utility model.
As shown in fig. 1, the automatic gas distribution device for mixed gas comprises a charging pipeline 1, a second gas conveying pipeline 2, a first gas conveying pipeline 3, a second gas control valve 4, a first gas control valve 5, a pressure sensor 6 before a regulating valve, a regulating valve 7, a flow meter 8, a pressure sensor 9 after the regulating valve, a charging control valve 10, a mixed gas container 11, an electronic balance 12, a vacuum pump pipeline, a vacuum pump 13, a vacuum control valve 14 and a temperature sensor.
The vacuum pump 13 adopts vacuum degree of 1 × 10-5Pa, high vacuum, two-stage vacuum pump.
The pressure sensor 6 before the regulating valve and the pressure sensor 9 after the regulating valve are high-precision vacuum pressure sensors, the measuring range is-0.1-40 MPa, and the precision is +/-0.075%.
The front end of the filling pipeline 1 is divided into two branches, one branch is a second gas conveying pipeline 2, and the other branch is a first gas conveying pipeline 3; the tail end of the filling pipeline 1 is connected with a mixed gas container 11; the front pressure sensor 6 of the regulating valve, the regulating valve 7, the flowmeter 8, the rear pressure sensor 9 of the regulating valve, the vacuum pump pipeline and the filling control valve 10 are sequentially connected between the front end and the tail end of the filling pipeline 1.
A second gas control valve 4 is arranged on the second gas conveying pipeline 2, a first gas control valve 5 is arranged on the first gas conveying pipeline 3, one end of a vacuum pump pipeline is connected with the filling pipeline 1, the other end of the vacuum pump pipeline is connected with a vacuum pump 13, and a vacuum control valve 14 is arranged on the vacuum pump pipeline; the mixed gas container 11 is placed on an electronic balance 12.
The temperature sensors are positioned at the pressure sensor 6 in front of the regulating valve and the pressure sensor 9 behind the regulating valve, and the temperature sensors and the pressure sensor 6 in front of the regulating valve and the pressure sensor 9 behind the regulating valve measure the front and back accurate pressure of the regulating valve 7 together by measuring the temperature of the gas in the filling pipeline 1, so that the regulating valve 7 is controlled to realize accurate control of the gas flow.
As shown in fig. 2, the second gas Control valve 4, the first gas Control valve 5, the pre-regulator pressure sensor 6, the regulator valve 7, the flow meter 8, the post-regulator pressure sensor 9, the charge Control valve 10, the electronic balance 12, the vacuum pump 13, the vacuum Control valve 14, and the temperature sensor are automatically controlled by a Distributed Control System (DCS).
The second gas control valve 4, the first gas control valve 5, the charging control valve 10 and the vacuum control valve 14 are stainless steel pneumatic diaphragm valves.
The flow meter 8 is a mass flow meter.
The second gas conveying pipeline 2 and the first gas conveying pipeline 3 are both provided with a negative pressure sensor and a high pressure sensor, the negative pressure sensor and the high pressure sensor are respectively connected with the DCS, the negative pressure sensor is used for replacing gas, and the high pressure sensor is used for controlling gas intake; the working conditions of all pipelines can be detected through the negative pressure sensor and the positive pressure sensor, and the DCS controls the gas distribution device to stop working when leakage or blockage occurs.
And the DCS is also connected with an audible and visual alarm.
The filling pipeline 1, the second gas conveying pipeline 2, the first gas conveying pipeline 3 and the vacuum pump pipeline are all stainless steel 316L electrolytic polishing pipelines.
The tubing was either 1/2 inches or 1/8 inches.
The line between the charge control valve 10 and the mixture container 11 is 1/8 inches to reduce the effect of line tension on the accuracy of the symmetry.
A DN5O bellows valve was used between the vacuum control valve 14 and the vacuum pump 13.
The automatic gas distribution device for mixed gas is used for configuring electronic mixed gas, taking the preparation of hydrogen-nitrogen mixed gas as an example, wherein the second gas is diluent gas nitrogen, and the first gas is component gas hydrogen; the method comprises the following specific steps:
(1) before preparing mixed gas, leakage detection is carried out on a filling pipeline 1 by respectively adopting a high-negative pressure maintaining method and a negative pressure maintaining method, the filling pipeline 1 is vacuumized to be less than or equal to 50Pa by a vacuum pump 13, whether the leakage condition of the filling pipeline 1 occurs or not is judged by a pressure sensor 6 before an adjusting valve and a pressure sensor 9 after the adjusting valve, then a second gas control valve 4 and a first gas control valve 5 are respectively opened, first gas and second gas are respectively introduced into the filling pipeline 1 and pressurized to be more than or equal to 10MPa, whether the leakage condition of the pipeline occurs or not is judged by the pressure sensor 6 before the adjusting valve and the pressure sensor 9 after the adjusting valve, leakage detection is completed, then the second gas control valve 4 and the first gas control valve 5 are closed, the filling pipeline 1 is vacuumized by the vacuum pump 13, and residual gas is removed.
(2) The DCS controls the opening and closing of the second gas control valve 4, the first gas control valve 5, the charging control valve 10, and the vacuum control valve 14, and performs a system check.
(3) The DCS reads the weight of the mixed gas container 11 on the electronic balance 12.
(4) Introducing first gas hydrogen into the mixed gas container 11 through the first gas conveying pipeline 3 and the filling pipeline 1, wherein the theoretical filling quality is about 30g, the opening of the regulating valve 7 is controlled to be the maximum by the DCS at first, when the residual introduction amount reaches 20g, the opening of the regulating valve 7 is determined by the DCS according to the front and rear pressures of the regulating valve, the flow of the gas is accurately controlled to reach the set flow of the flowmeter 8 to be 5g/s, the first gas slowly enters the mixed gas container 11, and the control precision of the filling gas quality is improved; after the first gas is filled, the DCS closes the first gas control valve 5 and evacuates the gas in the filling line 1 by the vacuum pump 13.
(5) Introducing second gas nitrogen into the mixed gas container 11 through the second gas conveying pipeline 2 and the filling pipeline 1, wherein the theoretical filling quality is about 7661g, the opening degree of the DCS control adjusting valve 7 is adjusted to the maximum initially, when the introduction amount reaches 80%, the residual introduction amount is about 1532g, the flow rate is adjusted to 20g/s by the DCS, when the introduction amount reaches 90%, the residual introduction amount is about 766g, the flow rate is adjusted to 10g/s by the DCS, the flow rate of the gas is accurately controlled to reach the set flow rate of the flowmeter 8, and the gas slowly enters the mixed gas container 11, so that the control accuracy of the quality of the introduced gas is improved; after the gas filling is completed, the DCS closes the second gas control valve 4 and evacuates the filling line 1 by means of the vacuum pump 13.
The gas distribution device solves the problems that the gas flow rate at the gas filling end point is uncontrollable, the gas mixture preparation precision is low and the manual control has misoperation in the existing gas mixture preparation process; the content accuracy of hydrogen and nitrogen in the hydrogen-nitrogen mixed gas configured in the mixed gas container 11 meets the precision requirement of the electronic mixed gas required in the production of semiconductors, Light Emitting Diodes (LEDs), photovoltaics and the like.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. The utility model provides an automatic gas distribution device of gas mixture which characterized in that: the gas distribution device comprises a charging pipeline (1), a second gas conveying pipeline (2), a first gas conveying pipeline (3), a second gas control valve (4), a first gas control valve (5), a pressure sensor (6) in front of a regulating valve, a regulating valve (7), a flowmeter (8), a pressure sensor (9) behind the regulating valve, a charging control valve (10), a mixed gas container (11), an electronic balance (12), a vacuum pump pipeline, a vacuum pump (13), a vacuum control valve (14) and a temperature sensor;
the front end of the filling pipeline (1) is divided into two branches, one branch is a second gas conveying pipeline (2), and the other branch is a first gas conveying pipeline (3); the tail end of the filling pipeline (1) is connected with the mixed gas container (11); a front pressure sensor (6) of a regulating valve, a regulating valve (7), a flowmeter (8), a rear pressure sensor (9) of the regulating valve, a vacuum pump pipeline and a filling control valve (10) are sequentially connected between the front end and the tail end of the filling pipeline (1);
a second gas control valve (4) is arranged on the second gas conveying pipeline (2), a first gas control valve (5) is arranged on the first gas conveying pipeline (3), one end of a vacuum pump pipeline is connected with the filling pipeline (1), the other end of the vacuum pump pipeline is connected with a vacuum pump (13), and a vacuum control valve (14) is arranged on the vacuum pump pipeline; the mixed gas container (11) is arranged on an electronic balance (12); the temperature sensors are positioned at the pressure sensor (6) in front of the regulating valve and the pressure sensor (9) behind the regulating valve;
the automatic control of the second gas control valve (4), the first gas control valve (5), the pressure sensor (6) before the regulating valve, the regulating valve (7), the flowmeter (8), the pressure sensor (9) after the regulating valve, the filling control valve (10), the electronic balance (12), the vacuum pump (13), the vacuum control valve (14) and the temperature sensor is realized through DCS.
2. The automatic gas distribution device for the mixed gas as claimed in claim 1, wherein: the electronic balance (12) adopts an ultra-high precision electronic scale with a comparator grade;
the vacuum pump (13) adopts the vacuum degree of 1 multiplied by 10-5A high vacuum two-stage vacuum pump of Pa;
the pressure sensor (6) before the regulating valve and the pressure sensor (9) after the regulating valve are high-precision vacuum pressure sensors, the measuring range is-0.1-40 MPa, and the precision is +/-0.075%.
3. The automatic gas distribution device for the mixed gas according to claim 1 or 2, characterized in that: the second gas control valve (4), the first gas control valve (5), the filling control valve (10) and the vacuum control valve (14) are stainless steel pneumatic diaphragm valves; the flowmeter (8) is a mass flowmeter.
4. The automatic gas distribution device for the mixed gas according to claim 1 or 2, characterized in that: and the second gas conveying pipeline (2) and the first gas conveying pipeline (3) are respectively provided with a negative pressure sensor and a high pressure sensor which are respectively connected with the DCS system.
5. The automatic gas distribution device for the mixed gas according to claim 1 or 2, characterized in that: and the DCS is connected with an audible and visual alarm.
6. The automatic gas distribution device for the mixed gas according to claim 1 or 2, characterized in that: the filling pipeline (1), the second gas conveying pipeline (2), the first gas conveying pipeline (3) and the vacuum pump pipeline are all stainless steel 316L electrolytic polishing pipelines; the tubing size is 1/2 inches or 1/8 inches; DN5O bellows valve is used between the vacuum control valve (14) and the vacuum pump (13).
7. The automatic gas distribution device for the mixed gas according to claim 1 or 2, characterized in that: the second gas control valve (4), the first gas control valve (5), the filling control valve (10) and the vacuum control valve (14) are stainless steel pneumatic diaphragm valves; the flowmeter (8) is a mass flowmeter;
a negative pressure sensor and a high pressure sensor are arranged on the second gas conveying pipeline (2) and the first gas conveying pipeline (3), and are respectively connected with the DCS;
the DCS is connected with an audible and visual alarm;
the filling pipeline (1), the second gas conveying pipeline (2), the first gas conveying pipeline (3) and the vacuum pump pipeline are all stainless steel 316L electrolytic polishing pipelines; the tubing size is 1/2 inches or 1/8 inches;
a DN5O corrugated pipe valve is adopted between the vacuum control valve (14) and the vacuum pump (13);
the line between the filling control valve (10) and the mixed gas container (11) adopts an 1/8-inch line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122735703.7U CN216499110U (en) | 2021-11-09 | 2021-11-09 | Automatic gas distribution device for mixed gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122735703.7U CN216499110U (en) | 2021-11-09 | 2021-11-09 | Automatic gas distribution device for mixed gas |
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| Publication Number | Publication Date |
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| CN216499110U true CN216499110U (en) | 2022-05-13 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202122735703.7U Active CN216499110U (en) | 2021-11-09 | 2021-11-09 | Automatic gas distribution device for mixed gas |
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| CN (1) | CN216499110U (en) |
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2021
- 2021-11-09 CN CN202122735703.7U patent/CN216499110U/en active Active
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