CN102042852B - Method for measuring minimum gas flow - Google Patents
Method for measuring minimum gas flow Download PDFInfo
- Publication number
- CN102042852B CN102042852B CN 201010523091 CN201010523091A CN102042852B CN 102042852 B CN102042852 B CN 102042852B CN 201010523091 CN201010523091 CN 201010523091 CN 201010523091 A CN201010523091 A CN 201010523091A CN 102042852 B CN102042852 B CN 102042852B
- Authority
- CN
- China
- Prior art keywords
- valve
- stabilizing chamber
- pressure stabilizing
- pressure
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Measuring Volume Flow (AREA)
- Control Of Positive-Displacement Pumps (AREA)
Abstract
The invention relates to a method for measuring minimum gas flow, comprising the following steps of: (1) pumping gas out of a pressure stabilizing chamber and a vacuum connection pipeline; (2) integrally roasting a device for degassing; (3) enabling the pressure stabilizing chamber to reach ultimate vacuum with a magnitude order of 10-6Pa by using a getter pump; (4) controlling pressure in the pressure stabilizing chamber to slowly rise; (5) charging inert gas with certain pressure into the pressure stabilizing chamber and obtaining gas pressure; (6) leading the inert gas in the pressure stabilizing chamber into a vacuum system through small holes; and (7) obtaining gas flow by utilizing gas pressure and small hole conductance. The method can take good use of the characteristics of a device for measuring minimum gas flow, and completely avoids measuring uncertainty caused by the deflation of the pressure stabilizing chamber and the inner wall of the pipeline, thereby ensuring the effective extension of a lower measuring limit and realizing the accurate measurement of the minimum gas flow with a flow value less than 1*10<-8>Pa.m<3>/s.
Description
Technical field
The present invention relates to a kind of apparatus and method of measuring minimum gas flow, particularly a kind of apparatus and method of utilizing the nonevaporable getter pump to measure minimum gas flow.
Background technology
In Measurement Laboratory, adopt the high-precision gas micro-flowmeter to measure and provide the known gas flow mostly.High-precision gas micro-flowmeter multiselect constant pressure type gas micro-flowmeter.
Document " Feng Yan, Cheng Yongjun, Zhang Dixin, etc. the performance test of constant pressure type gas micro-flowmeter. vacuum science and technology journal 25 (3), 2005. " to have introduced when not adopting the nonevaporable getter pump to bleed, the uncertainty of measurement that the wall venting causes is 10
-8Pa.m
3/ s magnitude is 0.6%, 10
-9Pa.m
3/ s magnitude is 3%.The venting of wall has limited 10
-8Pa.m
3/ s magnitude is with the accurate measurement of down-off.The accurate measurement range of constant pressure type gas micro-flowmeter is (1 * 10
-8～1 * 10
-4) Pa.m
3/ s.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art part, a kind of apparatus and method of measuring minimum gas flow are provided, eliminate the influence of wall venting fully, adopt fixed flow inducing defecation by enema and suppository measurement gas flow, make flow value less than 1 * 10
-8Pa.m
3The gas flow of/s can accurately be measured, and the measurement lower limit of flow has been extended to 10
-13Pa.m
3/ s magnitude.
The invention provides a kind of device of measuring minimum gas flow, comprise gas cylinder, micrometering valve, pressure stabilizing chamber, four valves, getter pump, molecular pump, forepump, capacitor thin film rule, magnetic suspension rotor gauge and aperture, wherein: gas cylinder is connected with pressure stabilizing chamber by micrometering valve, aperture links to each other with pressure stabilizing chamber by valve one with valve two backs in parallel one end, one end links to each other with vacuum system, getter pump links to each other with pressure stabilizing chamber by valve three, forepump is connected with pressure stabilizing chamber by valve four with molecular pump polyphone back, and capacitor thin film rule and magnetic suspension rotor gauge directly are connected on the wall of pressure stabilizing chamber.
Described getter pump is the nonevaporable getter pump, and molecular pump is that oil-free scroll molecular pump, forepump are dried pump, and valve is the ultrahigh vacuum angle valve, and the molecular flow conductance of aperture is 10
-9m
3The gas of storing in/s the order of magnitude, gas cylinder is high purity inert gas.
The present invention also provides a kind of method of measuring minimum gas flow, may further comprise the steps:
(1) opens valve one, valve two, valve four, start forepump and molecular pump successively, pressure stabilizing chamber and connection vacuum pipe are bled;
(2) carry out bakeout degassing to installing integral body, baking temperature keeps 60～80h after rising to separately peak respectively with the uniform speed;
(3) during the baking maximum temperature keeps, open the connection valve of getter pump, getter pump is activated, stop after activating 2～4h, close getter pump and connect valve, and then reduce to room temperature gradually with the uniform speed, after temperature returns to room temperature, open getter pump again and connect valve, continue the 24～48h that bleeds, in pressure stabilizing chamber, reach 10
-6The end vacuum of the Pa order of magnitude;
(4) valve-off one, valve four, the interior pressure of pressure stabilizing chamber this moment begins slow rising;
(5) treat pressure stability in the pressure stabilizing chamber after, regulate micrometering valve, give the inert gas that charges into certain pressure in the pressure stabilizing chamber; Obtain the pressure of gas by capacitor thin film rule 11 and magnetic suspension rotor gauge 12;
(6) open valve one, valve-off two is incorporated into the inert gas in the pressure stabilizing chamber in the vacuum system by aperture;
(7) conductance of pressure by gas and aperture obtains the flow of gas.
Wherein, be 120～150 ℃ to installing the highest whole baking temperature in the step (2), the uniform speed that baking temperature rises and descends is 20～40 ℃/h.
Activationary temperature to getter pump in the step (3) is 450～500 ℃.
The present invention's beneficial effect compared with prior art is:
(1) adopt getter pump that pressure stabilizing chamber and vacuum pipe thereof are bled, the uncertainty of measurement of having avoided the venting of pressure stabilizing chamber and inner-walls of duct to cause has fully guaranteed effective extension of measurement lower limit, makes flow value less than 1 * 10
-8Pa.m
3The minimum gas flow of/s can accurately be measured.
(2) adopt fixed flow inducing defecation by enema and suppository measurement gas flow, make the constant pressure type flowmeter become simply, make things convenient for to the extension of low discharge more.
Description of drawings
Fig. 1 is that the present invention utilizes the nonevaporable getter pump to measure the structure drawing of device of minimum gas flow.
Among the figure: 1-gas cylinder, 2-micrometering valve, 4-valve one, 5-valve two, 6-connect valve, 8-valve four, 3-pressure stabilizing chamber, 7-getter pump, 9-molecular pump, 10-forepump, 11-capacitor thin film rule, 12-magnetic suspension rotor gauge, 13-aperture.
Embodiment
Shown in Figure 1 is a preferred embodiment of the present invention, comprise gas cylinder 1, micrometering valve 2, pressure stabilizing chamber 3, valve 1, valve 25, connect valve 6, getter pump 7, valve 48, molecular pump 9, forepump 10, capacitor thin film rule 11, magnetic suspension rotor gauge 12 and aperture 13 are formed, gas cylinder 1 is connected with pressure stabilizing chamber 3 by micrometering valve 2, aperture 13 links to each other with pressure stabilizing chamber 3 by valve 1 with valve 25 backs in parallel one end, one end links to each other with vacuum system, getter pump 7 links to each other with pressure stabilizing chamber 3 by connecting valve 6, forepump 10 is connected with pressure stabilizing chamber 3 by valve 48 with molecular pump 9 polyphone backs, and capacitor thin film rule 11 and magnetic suspension rotor gauge 12 directly are connected on the wall of pressure stabilizing chamber 3.
Wherein, getter pump 7 is the nonevaporable getter pump, and molecular pump 9 is that oil-free scroll molecular pump, forepump 10 are dried pump, and connecting valve 6 is the ultrahigh vacuum angle valve, and the molecular flow conductance of aperture 13 is 10
-9m
3/ s the order of magnitude, the gas of storing in the gas cylinder 1 is high purity inert gas.
The measuring principle of this device is: after using molecular pump 9, forepump 10 and getter pump 7 that pressure stabilizing chamber 3 is evacuated to end vacuum, use getter pump 7 to keep, because 7 pairs of inert gases of getter pump do not have pumping speed, can make pressure stabilizing chamber 3 reach higher final vacuum; Inert gas flows into pressure stabilizing chamber 3 from gas cylinder 1, can obtain the pressure of gas by capacitor thin film rule 11 and magnetic suspension rotor gauge 12; Can obtain gas flow by the conductance of aperture 13 and the pressure of gas.
The method that present embodiment adopts is:
(1) opens valve 1, valve 25, valve 48, start forepump 10 and molecular pump 9 successively, pressure stabilizing chamber 3 and connection vacuum pipe are bled;
(2) carry out bakeout degassing to installing integral body, baking temperature keeps 72h after rising to separately peak respectively with the uniform speed of 30 ℃/h;
(3) during the baking maximum temperature keeps, open the connection valve 6 of getter pump 7, getter pump 7 is activated, and activationary temperature is 500 ℃, stops behind the activation 2h, close getter pump 7 and connect valve 6, and then reduce to room temperature gradually with the uniform speed of 30 ℃/h, after temperature returns to room temperature, open getter pump 7 again and connect valves 6, continue the 24h that bleeds, this moment, pressure stabilizing chamber 3 interior vacuum tightnesss were 2 * 10
-6Pa;
(4) valve-off 1, valve 48, this moment, pressure stabilizing chamber 3 interior pressure began slow rising;
(5) treat after the pressure stability in the pressure stabilizing chamber 34 * 10
-5Pa regulates micrometering valve 2, gives the He that charges into certain pressure in the pressure stabilizing chamber 3, reaches stable behind the 10min, and the pressure that records in the pressure stabilizing chamber 3 with magnetic suspension rotor gauge 12 is 6.4165 * 10
-4Pa;
(6) open valve 1, valve-off 25 is incorporated into the inert gases in the pressure stabilizing chamber 3 in the vacuum system by aperture 13, reaches mobile equilibrium behind the 10min, and then the gas flow that provides of this device is calculated by (1) formula
Q＝p
0·C
He..............................................(1)
In the formula: Q-flow, Pa.m
3/ s;
P
0Gaseous tension in the-pressure stabilizing chamber, Pa;
C
He-under the molecular flow condition, aperture 13 is with respect to the conductance of He, m
3/ s.
Wherein, record C in advance
HeBe 1.38 * 10
-9m
3/ s.
With P
0=6.4165 * 10
-4Pa, C
He=1.38 * 10
-9m
3/ s is substitution formula (1) respectively, and the measured value that calculates flow is 8.855 * 10
-13Pa.m
3/ s.
Claims (3)
1. method of measuring minimum gas flow, it is characterized in that: described measuring method utilization such as lower device are realized, gas cylinder (1) in this device is connected with pressure stabilizing chamber (3) by micrometering valve (2), aperture (13) links to each other with pressure stabilizing chamber (3) by valve one (4) with valve two (5) backs in parallel one end, one end links to each other with vacuum system, getter pump (7) links to each other with pressure stabilizing chamber (3) by connecting valve (6), forepump (10) is connected with pressure stabilizing chamber (3) by valve four (8) with molecular pump (9) polyphone back, and capacitor thin film rule (11) and magnetic suspension rotor gauge (12) directly are connected on the wall of pressure stabilizing chamber (3);
The method of the minimum gas flow of described measurement may further comprise the steps:
(1) opens valve one (4), valve two (5), valve four (8), start forepump (10) and molecular pump (9) successively, pressure stabilizing chamber (3) and connection vacuum pipe are bled;
(2) carry out bakeout degassing to installing integral body, baking temperature keeps 60～80h after rising to separately peak respectively with the uniform speed;
(3) during the baking maximum temperature keeps, open the connection valve (6) of getter pump (7), getter pump (7) is activated, stop after activating 2～4h, close getter pump and connect valve, and then reduce to room temperature gradually with the uniform speed, after temperature returns to room temperature, open getter pump again and connect valve, continue the 24～48h that bleeds, in pressure stabilizing chamber (3), reach 10
-6The end vacuum of the Pa order of magnitude;
(4) valve-off one (4), valve four (8), the pressure in pressure stabilizing chamber this moment (3) begins slow rising;
(5) treat pressure stability in the pressure stabilizing chamber (3) after, regulate micrometering valve (2), give the inert gas that charges into certain pressure in the pressure stabilizing chamber (3); Obtain the pressure of gas by capacitor thin film rule (11) and magnetic suspension rotor gauge (12);
(6) open valve one (4), valve-off two (5) is incorporated into the inert gas in the pressure stabilizing chamber (3) in the vacuum system by aperture (13);
(7) conductance of pressure by gas and aperture (13) obtains the flow of gas.
2. a kind of method of measuring minimum gas flow according to claim 1 is characterized in that, is 120～150 ℃ to installing the highest whole baking temperature in the step (2), and the uniform speed that baking temperature rises and descends is 20～40 ℃/h.
3. a kind of method of measuring minimum gas flow according to claim 1 is characterized in that, the activationary temperature to getter pump in the step (3) is 450～500 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010523091 CN102042852B (en) | 2010-10-26 | 2010-10-26 | Method for measuring minimum gas flow |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010523091 CN102042852B (en) | 2010-10-26 | 2010-10-26 | Method for measuring minimum gas flow |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102042852A CN102042852A (en) | 2011-05-04 |
| CN102042852B true CN102042852B (en) | 2011-12-21 |
Family
ID=43909206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201010523091 Active CN102042852B (en) | 2010-10-26 | 2010-10-26 | Method for measuring minimum gas flow |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102042852B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102937467A (en) * | 2012-11-12 | 2013-02-20 | 中国航天科技集团公司第五研究院第五一〇研究所 | All-metal gas micro-flow meter |
| CN103644947B (en) * | 2013-12-17 | 2017-01-18 | 东北大学 | Gas micro-flow measuring device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1816444A2 (en) * | 2006-02-07 | 2007-08-08 | Yamatake Corporation | Package structure of sensor and flow sensor having the same |
| JP2007322221A (en) * | 2006-05-31 | 2007-12-13 | Aichi Tokei Denki Co Ltd | Ultrasound flowmeter |
| CN201203503Y (en) * | 2007-12-28 | 2009-03-04 | 中国航天科技集团公司第五研究院第五一〇研究所 | Constant pressure type positive-pressure leak hole calibrating apparatus variable-capacity chamber |
| CN201314833Y (en) * | 2008-12-22 | 2009-09-23 | 中国航天科技集团公司第五研究院第五一〇研究所 | Measuring device for the size change of corrugated pipe in transfiguration chamber for constant pressure gas flow indicator |
-
2010
- 2010-10-26 CN CN 201010523091 patent/CN102042852B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1816444A2 (en) * | 2006-02-07 | 2007-08-08 | Yamatake Corporation | Package structure of sensor and flow sensor having the same |
| JP2007322221A (en) * | 2006-05-31 | 2007-12-13 | Aichi Tokei Denki Co Ltd | Ultrasound flowmeter |
| CN201203503Y (en) * | 2007-12-28 | 2009-03-04 | 中国航天科技集团公司第五研究院第五一〇研究所 | Constant pressure type positive-pressure leak hole calibrating apparatus variable-capacity chamber |
| CN201314833Y (en) * | 2008-12-22 | 2009-09-23 | 中国航天科技集团公司第五研究院第五一〇研究所 | Measuring device for the size change of corrugated pipe in transfiguration chamber for constant pressure gas flow indicator |
Non-Patent Citations (2)
| Title |
|---|
| 李得天等.中国真空计量发展概述.《真空与低温》.2004,(第01期),6-16页. * |
| 郭美如等.定容式流导法气体微流量校准装置测量不确定度的评定.《真空》.2007,(第02期),55-58页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102042852A (en) | 2011-05-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101995275B (en) | Static expansion method vacuum standard based method for measuring minimum gas flow | |
| CN102052940B (en) | Device for measuring extremely-low gas flow based on static expansion vacuum standard | |
| CN101713696B (en) | Device and method for calibrating flow-dividing vacuum leaking hole | |
| CN101995277B (en) | Device for measuring ultralow gas flow | |
| CN102944356B (en) | Extremely high vacuum gauge calibration device and method | |
| CN102042852B (en) | Method for measuring minimum gas flow | |
| CN109029619B (en) | Volume measuring device based on dynamic differential pressure attenuation | |
| CN104345087B (en) | A kind of calibrating installation of magnetic deflection mass spectrometer and calibration steps | |
| CN105004479B (en) | Ion gauge and mass spectrograph calibrating installation and method based on normal pressure measurement | |
| CN100395531C (en) | Bypass type ultrahigh and extreme-high vacuum gauge calibrating device and method thereof | |
| CN102393275A (en) | Calibration apparatus of on-site wide-range vacuum gauge and method thereof | |
| CN103808458A (en) | Device and method for testing suction and vent quantity of vacuum gauge based on dynamic flow method | |
| RU2015121116A (en) | METHOD AND DEVICE FOR SUBMITTING FUEL TO A GAS TURBINE | |
| CN109655372A (en) | A kind of PdO getter inspiratory capacity test device and method | |
| CN205094424U (en) | Static force accuracy testing arrangement based on pressure dynamic balance | |
| CN101710014B (en) | Device and method for measuring pumping speed and outgasing rate of ionization gauge | |
| CN202216802U (en) | Wide-range in-situ calibrating device for vacuum gauge | |
| CN104155425B (en) | A kind of method of high precision PCT tester and test alloy material storing hydrogen PCT | |
| CN100565182C (en) | Extend the method for calibration lower limit of static expanding method vacuum standard device | |
| CN203297103U (en) | Movable air intake control valve of screw air compressor | |
| CN111220326A (en) | Calibration device and method for calibrating vacuum gauge by using vacuum leak hole | |
| CN102628639A (en) | Vacuum drying device and vacuum drying control method | |
| CN112781787B (en) | Vacuum gauge calibration device and method based on exponential decay method | |
| CN202676250U (en) | Standard flowmeter | |
| CN114965152A (en) | System for testing NEG (negative electrode active gas) air suction performance based on fixed flow guide element improved constant pressure method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |