Portable standard gas supply device and method

Abstract

The invention relates to a portable standard gas supply device and method. The portable standard gas supply device comprises a gas source, a pressure reducing valve, a high-pressure stop valve, a pressure stabilizing chamber, a micrometering valve, a gas distribution chamber, an absolute pressure sensor, a first capacitance film gauge, a second capacitance film gauge, a Pirani vacuum gauge, a first high-vacuum angle valve, a second high-vacuum angle valve and a vacuumizing system. According to the portable standard gas supply device and method, through reasonable design, the device and the pipeline have the functions of heating, gas extraction and purification, replacement, portability and the like, the gas purity is guaranteed from the source, pollution of residual gas or organic matter is reduced, measurement errors caused by unreasonable design are reduced, and the measurement accuracy is improved. The accuracy of the prepared standard gas pressure and components is ensured to the maximum extent; the gas distribution precision is improved, the uncertainty of the gas distribution concentration is reduced, the requirement of field dynamic gas distribution can be met, and the method is simple, feasible and easy to operate.

Description

Technical Field

[0001] The present invention relates to the technical field of supplying standard gas, and more specifically, to a portable standard gas supply device and method. Background Art

[0002] The common bottom leakage monitoring system is mainly used for the total pressure of the common bottom cavity of the three-stage cryogenic tank of the new generation rocket, as well as the monitoring of the concentration of dangerous gases such as H2 and O2. The calibration of the common bottom leakage monitoring system mainly calibrates the core instruments, vacuum gauges and mass spectrometers. During calibration, it is necessary to prepare standard gases with known component content, introduce the prepared standard gases into the exhaust pipeline installed at the launch site, and then use the common bottom leakage monitoring system and calibration device at the launch site to measure the total pressure and H2 and O2 gas concentrations in the exhaust pipeline respectively. The calibration coefficient is obtained by the ratio of the measurement results of the two devices, thereby achieving the calibration purpose. Therefore, precise control of the pressure and composition of the standard gas is a prerequisite for ensuring accurate and reliable calibration results.

[0003] As the measurement standard of atmospheric composition, standard gas has been widely used in scientific research, atmospheric environment monitoring, instrument calibration, chemical product inspection and other fields. Many qualified standard gas manufacturers can prepare standard gas according to customer requirements, and there are also many units and institutions at home and abroad that conduct research and production of standard substances. However, the standard gas prepared using the existing standard gas preparation method generally has problems such as low accuracy and short validity period. Therefore, a portable standard gas supply device and method are invented to solve the problems existing in the prior art. Summary of the invention

[0004] The embodiments of the present application provide a portable standard gas supply device and method. In order to have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a general review, nor is it intended to identify key / important components or describe the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0005] The embodiment of the present application provides a portable standard gas supply device, which includes: a gas source, a pressure reducing valve, a high-pressure stop valve, a pressure stabilizing chamber, a fine-tuning valve, a gas distribution chamber, an absolute pressure sensor, a first capacitance film gauge, a second capacitance film gauge, a Pirani vacuum gauge, a first high vacuum angle valve, a second high vacuum angle valve, and a vacuum pumping system, wherein:

[0006] The gas source is connected to the pressure stabilizing chamber, and the pressure reducing valve and the high-pressure shut-off valve are sequentially arranged on the connected pipeline;

[0007] The pressure stabilizing chamber is provided with the absolute pressure sensor, and the absolute pressure sensor is used to monitor the pressure of the pressure stabilizing chamber;

[0008] The pressure stabilizing chamber is connected to the gas distribution chamber via the fine-tuning valve;

[0009] The first capacitance film gauge, the second capacitance film gauge, and the Pirani vacuum gauge are connected to the gas distribution chamber for monitoring and accurately measuring the pressure of the gas distribution chamber;

[0010] The vacuum pumping system is connected to the pressure stabilizing chamber and the gas distribution chamber. The first high vacuum angle valve is arranged on the pipeline connecting the vacuum pumping system and the pressure stabilizing chamber, and the second high vacuum angle valve is arranged on the pipeline connecting the vacuum pumping system and the gas distribution chamber.

[0011] According to a preferred embodiment, the stabilizing chamber adopts a cylindrical structure design, and the preparation of the mixed gas and the adjustment of the gas concentration can be achieved through the transition of the stabilizing chamber.

[0012] According to a preferred embodiment, the gas distribution chamber adopts a spherical structure design and is equipped with a high-temperature baking degassing module, and the background leakage rate is less than 5×10 -9 Pa·m 3 / s.

[0013] According to a preferred embodiment, the front pump of the vacuum pumping system is a vortex dry pump, which is used to extract and replace the background gas in the pressure stabilizing chamber and the gas distribution chamber during the gas distribution process.

[0014] According to a preferred embodiment, the main pump of the vacuum system is a turbomolecular pump, which can fully remove and replace the impurity gases in the pressure stabilization chamber and the gas distribution chamber.

[0015] According to a preferred embodiment, the gas source is stored in a standard steel cylinder, and the mixed gas is configured by replacing the steel cylinder.

[0016] According to another aspect of a preferred embodiment, the present application provides a portable standard gas supply method, the method comprising:

[0017] Step 1, starting the vacuum pumping system, opening the first high vacuum angle valve and the second high vacuum angle valve, and vacuuming the pressure stabilizing chamber, the gas distribution chamber and the pipeline;

[0018] Step 2, starting the absolute pressure sensor, the first capacitance film vacuum gauge, the second capacitance film vacuum gauge, and the Pirani vacuum gauge, and observing and recording the readings;

[0019] Step 3, after the first capacitance film vacuum gauge, the second capacitance film vacuum gauge, and the Pirani vacuum gauge are fully preheated and stabilized, close the first high vacuum angle valve, open the high pressure stop valve, open the gas source, adjust the pressure reducing valve, introduce the high purity gas in the gas source into the pressure stabilizing chamber, and observe and record the indication of the absolute pressure sensor;

[0020] Step 4: When the pressure value of the stabilizing chamber has no obvious fluctuation and tends to equilibrium, the high-pressure stop valve and the second high-vacuum angle valve are closed, and the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge are continuously recorded. The fine-tuning valve is slowly adjusted to introduce the high-purity gas in the stabilizing chamber into the gas distribution chamber, and the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge are continuously recorded. The indicated values ​​of the vacuum gauges have no obvious fluctuation, and the fine-tuning valve is closed after tending to equilibrium.

[0021] Step 5, replacing the gas source, adjusting the pressure reducing valve, opening the high-pressure stop valve, introducing the high-purity gas in the gas source into the pressure stabilizing chamber, opening the first high vacuum angle valve, and extracting the gas in the pipeline and the pressure stabilizing chamber;

[0022] Step 6, after repeating step 5 for 3 to 6 times, close the first high vacuum angle valve, adjust the pressure reducing valve, introduce the high-purity gas in the gas source into the pressure stabilizing chamber, and observe and record the indication of the absolute pressure sensor;

[0023] Step 7: When the pressure value has no obvious fluctuation and tends to balance, close the high-pressure stop valve, slowly adjust the fine-tuning valve, introduce the high-purity gas in the pressure stabilizing chamber into the gas distribution chamber, and continuously record the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge. When the vacuum gauge indication value has no obvious fluctuation, close the fine-tuning valve after tending to balance.

[0024] Step 8, repeat steps 5 to 7 until all the gas to be measured is introduced into the gas distribution chamber;

[0025] Step 9, processing the recorded data to obtain the concentration value of each gas component.

[0026] The technical solution provided by the embodiments of the present application may have the following beneficial effects:

[0027] In an embodiment of the present application, the portable standard gas supply device includes: a gas source, a pressure reducing valve, a high-pressure stop valve, a pressure stabilizing chamber, a fine-tuning valve, a gas distribution chamber, an absolute pressure sensor, a first capacitance film gauge, a second capacitance film gauge, a Pirani vacuum gauge, a first high vacuum angle valve, a second high vacuum angle valve, and a vacuum pumping system, wherein:

[0028] The gas source is connected to the pressure stabilizing chamber, and the pressure reducing valve and the high-pressure shut-off valve are sequentially arranged on the connected pipeline;

[0029] The pressure stabilizing chamber is provided with the absolute pressure sensor, and the absolute pressure sensor is used to monitor the pressure of the pressure stabilizing chamber;

[0030] The pressure stabilizing chamber is connected to the gas distribution chamber via the fine-tuning valve;

[0031] The first capacitance film gauge, the second capacitance film gauge, and the Pirani vacuum gauge are connected to the gas distribution chamber for monitoring and accurately measuring the pressure of the gas distribution chamber;

[0032] The vacuum pumping system is connected to the pressure stabilizing chamber and the gas distribution chamber. The first high vacuum angle valve is arranged on the pipeline connecting the vacuum pumping system and the pressure stabilizing chamber, and the second high vacuum angle valve is arranged on the pipeline connecting the vacuum pumping system and the gas distribution chamber. The portable standard gas supply method comprises: step 1, starting the vacuum pumping system, opening the first high vacuum angle valve and the second high vacuum angle valve, and vacuuming the stabilizing chamber, the gas distribution chamber and the pipeline; step 2, starting the absolute pressure sensor, the first capacitance film vacuum gauge, the second capacitance film vacuum gauge and the Pirani vacuum gauge, and observing and recording the readings; step 3, after the first capacitance film vacuum gauge, the second capacitance film vacuum gauge and the Pirani vacuum gauge are fully preheated and stabilized, closing the first high vacuum angle valve, opening the high pressure stop valve, opening the gas source, adjusting the pressure reducing valve, introducing the high purity gas in the gas source into the stabilizing chamber, and observing and recording the indicated value of the absolute pressure sensor; step 4, after the pressure value of the stabilizing chamber has no obvious fluctuation and tends to balance, closing the high pressure stop valve and the second high vacuum angle valve, continuously recording the indicated values ​​of the first capacitance film vacuum gauge, the second capacitance film vacuum gauge and the Pirani vacuum gauge, slowly adjusting the fine adjustment valve, introducing the high purity gas in the stabilizing chamber into the gas distribution chamber, and continuously recording the indicated value of the first capacitance film vacuum gauge. The vacuum gauge, the second capacitance film vacuum gauge, and the Pirani vacuum gauge have no obvious fluctuations in the vacuum gauge indication value, and the fine-tuning valve is closed after it tends to balance; Step 5, replace the gas source, adjust the pressure reducing valve, open the high-pressure stop valve, introduce the high-purity gas in the gas source into the pressure stabilizing chamber, open the first high vacuum angle valve, and remove the gas in the pipeline and the pressure stabilizing chamber; Step 6, repeat step 5 3 to 6 times, close the first high vacuum angle valve, adjust the pressure reducing valve, introduce the high-purity gas in the gas source into the pressure stabilizing chamber, observe and record The absolute pressure sensor indicates the value; Step 7, the pressure value has no obvious fluctuations, and after it tends to balance, close the high-pressure stop valve, slowly adjust the fine-tuning valve, introduce the high-purity gas in the pressure-stabilizing chamber into the gas distribution chamber, and continuously record the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge. The vacuum gauge indication value has no obvious fluctuations, and after it tends to balance, close the fine-tuning valve; Step 8, repeat steps 5 to 7 until all the measured gases are introduced into the gas distribution chamber; Step 9, process the recorded data to obtain the concentration content value of each gas component. A portable standard gas supply device and method described in the embodiment of the present application is simple, feasible, and easy to operate. It reasonably selects pressure measuring instruments that are not affected by the type of gas, so that the device and pipeline have functions such as heating, air extraction purification, replacement, and portability, ensuring gas purity from the source, reducing residual gas or organic pollution, and reducing measurement errors caused by unreasonable design; the ultimate pressure of the gas distribution chamber is designed to be 10- 6Pa, the pressure rise in the gas distribution chamber can be controlled to be less than 0.5Pa within 30 minutes, and the resulting gas distribution pressure fluctuation is less than 0.5%; in order to maximize the accuracy of the prepared standard gas pressure and components, reduce and avoid various possible outgassing and contamination, the volumes of various chambers are designed to be as small as possible to reduce the existence of dead space; the calibration system connected to it uses a double-aperture sampling method, and the gas in the sampling pipeline is in a molecular flow state, which effectively reduces the mass discrimination effect; in addition, the present application adopts a standard steel cylinder to store the gas source, and the gas source can be replaced according to specific needs. It is small in size and light in weight, can meet the needs of on-site dynamic gas distribution, improves the gas distribution accuracy, and reduces the uncertainty of gas distribution concentration.

[0033] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0035] Figure 1 is a structural schematic diagram of a portable standard gas supply device provided in an embodiment of the present application;

[0036] Figure 2 It is a flow chart of a portable standard gas supply method provided in an embodiment of the present application.

[0037] Figure markings: 1-gas source; 2-pressure reducing valve; 3-high-pressure stop valve; 4-absolute pressure sensor; 5-pressure stabilizing chamber; 6-fine-tuning valve; 7-first capacitance film gauge; 8-Pirani vacuum gauge; 9-second capacitance film gauge; 10-gas distribution chamber; 11-calibration interface valve; 12-first high vacuum angle valve; 13-second high vacuum angle valve; 14-vacuum extraction system; 15-calibration system. DETAILED DESCRIPTION

[0038] The following description and the drawings sufficiently illustrate specific embodiments of the invention to enable those skilled in the art to practice them.

[0039] It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples of systems and methods consistent with some aspects of the present invention as detailed in the attached claims.

[0041] In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previously associated objects are in an "or" relationship.

[0042] The following will be combined with the attached Figure 1 -Attached Figure 2 , a portable standard gas supply device provided in an embodiment of the present application is introduced in detail.

[0043] See also Figure 1 , is a schematic diagram of the structure of a portable standard gas supply device provided in the embodiment of the present application. Figure 1 As shown, a portable standard gas supply device described in an embodiment of the present application may include: a gas source (1), a pressure reducing valve (2), a high-pressure stop valve (3), a pressure stabilizing chamber (5), a fine-tuning valve (6), a gas distribution chamber (10), an absolute pressure sensor (4), a first capacitance film gauge (7), a second capacitance film gauge (9), a Pirani vacuum gauge (8), a first high vacuum angle valve (12), a second high vacuum angle valve (13), and a vacuum pumping system (14), wherein:

[0044] The gas source (1) is connected to the pressure stabilizing chamber (5), and a pressure reducing valve (2) and a high-pressure stop valve (3) are sequentially arranged on the connecting pipeline;

[0045] The pressure stabilizing chamber (5) is provided with an absolute pressure sensor (4), and the absolute pressure sensor (4) is used to monitor the pressure of the pressure stabilizing chamber (5);

[0046] The pressure stabilizing chamber (5) is connected to the gas distribution chamber (10) via a fine-tuning valve (6);

[0047] The gas distribution chamber (10) is connected with a first capacitance film gauge (7), a second capacitance film gauge (9), and a Pirani vacuum gauge (8) for monitoring and accurately measuring the pressure of the gas distribution chamber (10);

[0048] The vacuum pumping system (14) is connected to the pressure stabilizing chamber (5) and the gas distribution chamber (10); a first high vacuum angle valve (12) is provided on the pipeline connecting the vacuum pumping system (14) and the pressure stabilizing chamber (5); and a second high vacuum angle valve (13) is provided on the pipeline connecting the vacuum pumping system (14) and the gas distribution chamber (10).

[0049] Specifically, in the embodiment of the present application, the full scale of the absolute pressure sensor (4) is 250 KPa, the measurement accuracy is 0.1% FS, and it is used for pressure monitoring of the stabilizing chamber (5); the stabilizing chamber (5) is designed with a cylindrical structure, with a volume of 1 L and a maximum working pressure of 0.2 MPa, and can realize gas distribution from the gas source (1) to the gas distribution chamber (10), ensuring that the gas distribution pressure is stable and adjustable, and the preparation of the mixed gas and the adjustment of the gas concentration can be realized through the transition of the stabilizing chamber (5); the gas distribution chamber (10) is designed with a spherical structure, with a volume of 5 L and a maximum working pressure of 0.1 MPa, and surface passivation, hydrogen burning and other treatments are required during the processing process. The purpose of surface passivation is to reduce the adsorption of gas molecules on the inner wall of the gas distribution chamber, and the purpose of hydrogen burning is to remove the attachment of hydrogen molecules to the inner surface of the gas distribution chamber (10), and the gas distribution chamber (10) is also equipped with a high-temperature baking degassing module, and the background leakage rate is less than 5×10 -9 Pa·m 3 / s; Under fully baked conditions, the ultimate pressure of the gas distribution chamber (10) can reach 10 -6 Pa, effectively reducing the background effect and improving the accuracy of standard mixed gas preparation; the vacuum system (14) is composed of a dry pump, a molecular pump, a pipeline and a valve, which is used to evacuate the pipeline, the gas distribution chamber (10) and the pressure stabilizing chamber (5) on the one hand, and to repeatedly evacuate and replace the pressure stabilizing chamber (5) and the front pipeline of the pressure stabilizing chamber (5) with nitrogen on the other hand; the front pump of the vacuum system (14) is a vortex dry pump with a pumping speed of 2L / s, which is used to extract and replace the background gas in the pressure stabilizing chamber (5) and the gas distribution chamber (10) during the gas distribution process, and has the characteristics of being oil-free and pollution-free; the main pump is a turbomolecular pump with a pumping speed of 100L / s, which can fully evacuate the pressure stabilizing chamber (5) and the gas distribution chamber (10) The impurity gas is extracted and replaced; in the embodiment of the present application, the gas source (1) is stored in a 4L standard steel cylinder, which is small in size and light in weight. The embodiment of the present application is equipped with three gases of high purity N2, H2, and O2. The mixed gas is prepared by replacing the steel cylinder, thereby completing the total pressure calibration and the H2 and O2 gas concentration calibration gas preparation requirements; the pipeline and the stabilizing chamber (5) after the replacement of the gas source (1) can be repeatedly evacuated and gas flushed by the high vacuum stop valve (3) and the vacuum pumping system (14), the purpose of which is to reduce the gas residue in the stabilizing chamber (5) and ensure that the concentration of the mixed gas is not affected by the residual gas; in the embodiment of the present application, the first capacitor film gauge (7) is selected from 1.3×10 3 The range of the second capacitance film gauge (9) is 1.3×105 The measuring range of the first capacitance film gauge (7) and the second capacitance film gauge (9) are respectively (0.13-1.3×10 3 )Pa and (13~1.3×10 5 )Pa, in addition, the measurement result of the capacitance film gauge is not affected by the type of gas, and the precision control of the gas components when the standard mixed gas is prepared can be achieved; it also includes a calibration interface valve (11) and a calibration system (15), wherein the function of the calibration interface valve (11) is to control the on-off of the gas supply device and the calibrated device.

[0050] The present application embodiment provides a flow chart of a portable standard gas supply method. Figure 2 As shown, the method of the embodiment of the present application may include the following steps:

[0051] Step 1, start the vacuum pumping system (14), open the first high vacuum angle valve (12) and the second high vacuum angle valve (13), and evacuate the pressure stabilizing chamber (5), the gas distribution chamber (10) and the pipeline;

[0052] Step 2, start the absolute pressure sensor (4), the first capacitance film vacuum gauge (7), the second capacitance film vacuum gauge (9), and the Pirani vacuum gauge (8), and observe and record the readings;

[0053] Step 3, after the first capacitance film vacuum gauge (7), the second capacitance film vacuum gauge (9) and the Pirani vacuum gauge (8) are fully preheated and stabilized, in the embodiment of the present application, after more than 1 hour, close the first high vacuum angle valve (12), open the high pressure stop valve (3), open the high purity H2 gas source (1), adjust the pressure reducing valve (2), introduce high purity H2 into the pressure stabilizing chamber (5), and observe and record the indication of the absolute pressure sensor (4);

[0054] Step 4: When the pressure value of the stabilizing chamber (5) has no obvious fluctuation and tends to balance, the high-pressure stop valve (3) is closed, the second high vacuum angle valve (13) is closed, the indications of the first capacitor film vacuum gauge (7), the second capacitor film vacuum gauge (9), and the Pirani vacuum gauge (8) are continuously recorded, the fine-tuning valve (6) is slowly adjusted, the high-purity H2 in the stabilizing chamber (5) is introduced into the gas distribution chamber (10), the indications of the first capacitor film vacuum gauge (7), the second capacitor film vacuum gauge (9), and the Pirani vacuum gauge (8) are continuously recorded, and the vacuum gauge indication value has no obvious fluctuation. When the vacuum gauge indicates balance, the fine-tuning valve (6) is closed;

[0055] Step 5, remove the high-purity H2 gas cylinder and replace it with a high-purity N2 gas source, adjust the pressure reducing valve (2), open the high-pressure stop valve (3), introduce high-purity N2 into the pipeline and the pressure stabilizing chamber (5), open the first high vacuum angle valve (12), and remove the gas in the pipeline and the pressure stabilizing chamber (5);

[0056] Step 6, after repeating step 5 for 3 to 6 times, close the first high vacuum angle valve (12), adjust the pressure reducing valve (2), introduce high-purity N2 into the pressure stabilizing chamber (5), and observe and record the indication of the absolute pressure sensor (4);

[0057] Step 7: When the pressure value has no obvious fluctuation and tends to balance, close the high-pressure stop valve (3), slowly adjust the fine-tuning valve (6), introduce the mixed gas of H2 and N2 in the pressure stabilizing chamber (5) into the gas distribution chamber (10), and continuously record the indications of the first capacitor film vacuum gauge (7), the second capacitor film vacuum gauge (9), and the Pirani vacuum gauge (8). When the indicated value of the vacuum gauge has no obvious fluctuation, close the fine-tuning valve (6) after it tends to balance.

[0058] Step 8, after repeating step 5 for 3 to 6 times, close the first high vacuum angle valve (12), remove the high-purity N2 gas cylinder, replace it with a high-purity O2 gas source, adjust the pressure reducing valve (2), introduce high-purity O2 into the pressure stabilizing chamber (5), and observe and record the indication of the absolute pressure sensor (4);

[0059] Step 9, when the pressure value has no obvious fluctuation and tends to balance, the high-pressure stop valve (3) is closed, the indications of the first capacitor film vacuum gauge (7), the second capacitor film vacuum gauge (9), and the Pirani vacuum gauge (8) are continuously recorded, the fine-tuning valve (6) is slowly adjusted, and the high-purity O2 in the pressure stabilizing chamber (5) is introduced into the gas distribution chamber (10), at which time the mixed gas in the gas distribution chamber is a mixed gas of N2, H2, and O2, the indications of the first capacitor film vacuum gauge (7), the second capacitor film vacuum gauge (9), and the Pirani vacuum gauge (8) are continuously recorded, and the vacuum gauge indications have no obvious fluctuation, and the fine-tuning valve (6) is closed after the pressure gauge tends to balance;

[0060] Step 10, data processing. Based on the gas distribution experience, the corresponding indications are selected from the recorded data of the first capacitance film vacuum gauge (7), the second capacitance film vacuum gauge (9), and the Pirani vacuum gauge (8) as the partial pressure of the mixed gas of N2, H2, and O2: Substitute into formula ① to calculate the concentration value of each measured gas component:

[0061]

[0062] Where: C i is the concentration of the measured gas i, percentage concentration; P i is the partial pressure of the gas i to be measured in the gas distribution chamber (10), in units of Pa; and n is the type of the gas to be measured.

[0063] In the embodiment of the present application, before the pressure stabilizing chamber (5), the gas distribution chamber (10) and the pipeline are installed, the parts need to be thoroughly cleaned, and when the device is debugged, the entire device is fully baked and degassed. The embodiment of the present application first calculates the partial pressure of each gas component according to the concentration of the gas to be matched and the total pressure, and then introduces the gas of the specified pressure (measured by the capacitance film gauge) into the gas distribution chamber (10) in sequence according to the principle of gas partial pressure from small to large. According to Dalton's law, the final total gas distribution pressure is equal to the sum of the partial pressures of various gas components, that is:

[0064]

[0065] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0066] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A portable standard gas supply device, characterized in that: include: Gas source, pressure reducing valve, high pressure stop valve, pressure stabilizing chamber, fine adjustment valve, gas distribution chamber, absolute pressure sensor, first capacitance film gauge, second capacitance film gauge, Pirani vacuum gauge, first high vacuum angle valve, second high vacuum angle valve, vacuum pumping system, including: The gas source is connected to the pressure stabilizing chamber, and the pressure reducing valve and the high-pressure shut-off valve are sequentially arranged on the connected pipeline; The pressure stabilizing chamber is provided with the absolute pressure sensor, and the absolute pressure sensor is used to monitor the pressure of the pressure stabilizing chamber; The pressure stabilizing chamber is connected to the gas distribution chamber via the fine-tuning valve; The first capacitance film gauge, the second capacitance film gauge, and the Pirani vacuum gauge are connected to the gas distribution chamber for monitoring and accurately measuring the pressure of the gas distribution chamber; The vacuum pumping system is connected to the pressure stabilizing chamber and the gas distribution chamber. The first high vacuum angle valve is arranged on the pipeline connecting the vacuum pumping system and the pressure stabilizing chamber, and the second high vacuum angle valve is arranged on the pipeline connecting the vacuum pumping system and the gas distribution chamber.

2. The portable standard gas supply device according to claim 1, characterized in that: The pressure stabilizing chamber adopts a cylindrical structure design, and the preparation of mixed gas and the adjustment of gas concentration can be achieved through the transition of the pressure stabilizing chamber.

3. The portable standard gas supply device according to claim 1, characterized in that: The gas distribution chamber adopts a spherical structure design and is equipped with a high-temperature baking degassing module. The background leakage rate is less than 5×10 -9 Pa·m 3 / s.

4. The portable standard gas supply device according to claim 1, characterized in that: The front pump of the vacuum pumping system is a vortex dry pump, which is used to extract and replace the background gas in the pressure stabilizing chamber and the gas distribution chamber during the gas distribution process.

5. The portable standard gas supply device according to claim 4, characterized in that: The main pump of the vacuum system is a turbomolecular pump, which can fully remove and replace the impurity gases in the pressure stabilization chamber and the gas distribution chamber.

6. The portable standard gas supply device according to claim 1, characterized in that: The gas source is stored in a standard steel cylinder, and the mixed gas is configured by replacing the steel cylinder.

7. A portable standard gas supply method, characterized in that: The portable standard gas supply device according to any one of claims 1 to 6, comprising: Step 1, starting the vacuum pumping system, opening the first high vacuum angle valve and the second high vacuum angle valve, and vacuuming the pressure stabilizing chamber, the gas distribution chamber and the pipeline; Step 2, starting the absolute pressure sensor, the first capacitance film vacuum gauge, the second capacitance film vacuum gauge, and the Pirani vacuum gauge, and observing and recording the readings; Step 3, after the first capacitance film vacuum gauge, the second capacitance film vacuum gauge, and the Pirani vacuum gauge are fully preheated and stabilized, close the first high vacuum angle valve, open the high pressure stop valve, open the gas source, adjust the pressure reducing valve, introduce the high purity gas in the gas source into the pressure stabilizing chamber, and observe and record the indication of the absolute pressure sensor; Step 4: When the pressure value of the stabilizing chamber has no obvious fluctuation and tends to equilibrium, the high-pressure stop valve and the second high-vacuum angle valve are closed, and the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge are continuously recorded. The fine-tuning valve is slowly adjusted to introduce the high-purity gas in the stabilizing chamber into the gas distribution chamber, and the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge are continuously recorded. The indicated values ​​of the vacuum gauges have no obvious fluctuation, and the fine-tuning valve is closed after tending to equilibrium. Step 5, replacing the gas source, adjusting the pressure reducing valve, opening the high-pressure stop valve, introducing the high-purity gas in the gas source into the pressure stabilizing chamber, opening the first high vacuum angle valve, and extracting the gas in the pipeline and the pressure stabilizing chamber; Step 6, after repeating step 5 for 3 to 6 times, close the first high vacuum angle valve, adjust the pressure reducing valve, introduce the high-purity gas in the gas source into the pressure stabilizing chamber, and observe and record the indication of the absolute pressure sensor; Step 7: When the pressure value has no obvious fluctuation and tends to balance, close the high-pressure stop valve, slowly adjust the fine-tuning valve, introduce the high-purity gas in the pressure stabilizing chamber into the gas distribution chamber, and continuously record the indications of the first capacitor film vacuum gauge, the second capacitor film vacuum gauge, and the Pirani vacuum gauge. When the vacuum gauge indication value has no obvious fluctuation, close the fine-tuning valve after tending to balance. Step 8, repeat steps 5 to 7 until all the gas to be measured is introduced into the gas distribution chamber; Step 9, processing the recorded data to obtain the concentration value of each gas component.

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