CN101458109A - Constant pressure type gas flowmeter transfiguration chamber bellows volume change measuring set - Google Patents
Constant pressure type gas flowmeter transfiguration chamber bellows volume change measuring set Download PDFInfo
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- CN101458109A CN101458109A CNA2008101883266A CN200810188326A CN101458109A CN 101458109 A CN101458109 A CN 101458109A CN A2008101883266 A CNA2008101883266 A CN A2008101883266A CN 200810188326 A CN200810188326 A CN 200810188326A CN 101458109 A CN101458109 A CN 101458109A
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Abstract
The invention relates to a device for measuring volume change of a bellows of a varactor chamber of a constant voltage type gas flow indicator, belonging to the technical field of vacuum measurement. The measuring device comprises an air supply system, a varactor chamber, a partition valve, a reference room pipeline, an absolute type pressure gauge, a differential pressure type pressure gauge, a translational mechanism, a standard container, vacuum valves and an air-bleed system. The air supply system is connected with the reference room pipeline by one vacuum valve, the air-bleed system is connected with the reference room pipeline by one vacuum valve, the absolute type pressure gauge is connected with the reference room pipeline, on end of the differentiated pressure type pressure gauge is connected with the reference room pipeline and the other end thereof is connected with a varactor chamber pipeline, one end of the bellows is connected with the translational mechanism and the other end thereof is connected with the varactor chamber pipeline by one vacuum valve, the standard container is connected with the varactor chamber pipeline by one vacuum valve, the varactor chamber pipeline and the reference room pipeline are connected by the partition valve. The device of the invention can carry out in situ measurement and carry out repeated measurement under operational condition.
Description
Technical field
The present invention relates to a kind of measurement mechanism that constant pressure type gas flow meter corrugated tube volume changes that is used for, belong to the vacuumatic measuring technical field.
Background technology
In document " German federal physical technique research institute (PTB) gas micro metering review; " vacuum science and technology "; 2003 the 4th phases, the 289th page～294 pages ", introduced a kind of assay method of PTB volume-changeable chamber bellows of constant pressure type gas flow meter volume change.This method is the weighing measurement method, method is as follows: charge into the water that distills and degas through 4 times after bellows component is vacuumized, place the container on the sensitive balance to be connected with one bellows component with a tubule, when corrugated tube is compressed, water is squeezed into container, after revising buoyancy of water and evaporation capacity, obtain corrugated tube volume variable quantity by quality and the density of measuring the water on the balance.
The weak point of this method is: in the measuring process, can not calibrate in situ, but the transfiguration chamber need be pulled down from vacuum plant, can cause vacuum system to be exposed to atmosphere like this, be unfavorable for keeping of vacuum system; Secondly, owing to use aqueous medium when measuring, need that corrugated tube is carried out PROCESS FOR TREATMENT after measurement finishes and just can reuse, this might cause between measured value and the actual use value and have error; Once more, the measuring process complexity, the Measuring Time cycle is long, and for example PTB has only carried out 3 measurements altogether in the period of 17.
Summary of the invention
The objective of the invention is to propose a kind of measurement mechanism of volume-changeable chamber bellows of constant pressure type gas flow meter volume change in order to overcome the deficiency of prior art.
The objective of the invention is to be achieved through the following technical solutions.
The measurement mechanism of a kind of volume-changeable chamber bellows of constant pressure type gas flow meter volume change of the present invention comprises air supply system, transfiguration chamber, cuts off valve, reference chamber pipeline, absolute type pressure gauge, differential pressure type pressure gauge, parallel moving mechanism, volumetric standard, first vacuum valve, second vacuum valve, the 3rd vacuum valve, the 4th vacuum valve and extract system.Wherein, the transfiguration chamber comprises corrugated tube and transfiguration chamber pipeline.
Air supply system is responsible for providing test gas.
The transfiguration chamber is used to hold gas.Wherein, corrugated tube is used for regulating the pressure of transfiguration chamber; Transfiguration chamber pipeline is used to connect corrugated tube and volumetric standard.
Cutting off valve is used for reference chamber pipeline and transfiguration chamber pipeline are separated.
The reference chamber pipeline is used to hold gas, keeps reference gas pressure constant.
The absolute type pressure gauge is used for the absolute pressure of witness mark chamber and transfiguration chamber.
The differential pressure type pressure gauge is used to write down the relative pressure that shutdown valve closes between back reference chamber pipeline and the transfiguration chamber pipeline to be changed.
Parallel moving mechanism is used at axial compression or stretching corrugated tube, and the gaseous tension that transfiguration chamber volume changes, transfiguration is indoor is changed.
Volumetric standard is used for transfiguration chamber gas and expands, and produces pressure differential, measures transfiguration chamber volume.
Extract system is responsible for finishing the vacuum pumping to reference chamber pipeline, transfiguration chamber and volumetric standard.
First vacuum valve is in closed condition, and second vacuum valve, the 3rd vacuum valve, the 4th vacuum valve all are in open mode, cuts off valve and is in open mode.
Annexation between above-mentioned each ingredient is:
Air supply system links to each other with the reference chamber pipeline by first vacuum valve, and extract system links to each other with the reference chamber pipeline by second vacuum valve, and absolute pressure formula pressure gauge links to each other with the reference chamber pipeline; Differential pressure type pressure gauge one end links to each other with the reference chamber pipeline, and the other end links to each other with transfiguration chamber pipeline; Corrugated tube one end links to each other with parallel moving mechanism, and the corrugated tube other end links to each other with transfiguration chamber pipeline by the 3rd vacuum valve; Volumetric standard links to each other with transfiguration chamber pipeline by the 4th vacuum valve; Transfiguration chamber pipeline links to each other by cutting off valve with the reference chamber pipeline enclosure.
The principle of work of above-mentioned measurement mechanism is:
In the transfiguration chamber, charge into the gas of certain known pressure, and gas is expand in the volumetric standard, record corrugated tube at the state of nature transfiguration chamber volume in following time.Then, at corrugated tube in the raw the time, to the indoor feeding known pressure of transfiguration gas, and compress bellows, make it produce corrugated tube volume and change, at this moment, the transfiguration room pressure will rise, and measure corrugated tube volume variable quantity.
Beneficial effect
1, adopts the isothermal expansion technology,, obtain the volume-changeable chamber bellows volume change, avoided volume-changeable chamber bellows to measure the back and used PROCESS FOR TREATMENT such as preceding degasification, baking processing, simplified measuring process by measurement gas pressure and standard volume parameter.
2, measuring process is simple, adopts in site measurement, has avoided the dismounting of transfiguration chamber, helps the maintenance and the maintenance of vacuum system.
3, the Measuring Time cycle lacks, and has removed the motive seal switching performance of piston and grease chamber, has reduced leakage, venting, helps the raising of measuring accuracy.
The instrument that uses when 4, measuring all utilizes the existing instrument of constant pressure type gas flow meter, does not need additional designs to use other instruments.
Description of drawings
Fig. 1 is the structural representation of apparatus of the present invention preferred implementation.
Wherein, 1-air supply system, 2-first vacuum valve, 3-reference chamber pipeline, 4-absolute type pressure gauge, 5-cuts off valve, the 6-parallel moving mechanism, 7-corrugated tube, 8-the 3rd vacuum valve, 9-transfiguration chamber pipeline, the 10-volumetric standard, 11-the 4th vacuum valve, 12-differential pressure type pressure gauge, the 13-extract system, 14-second vacuum valve.
Embodiment
Below in conjunction with Figure of description, the preferred implementation of apparatus of the present invention is elaborated.
As shown in Figure 1, the measurement mechanism of preferred volume-changeable chamber bellows of constant pressure type gas flow meter volume change of the present invention comprises air supply system 1, the first vacuum valve 2, the 3rd vacuum valve 8, the four vacuum valves 11, the second vacuum valves 14, cut off valve 5, reference chamber pipeline 3, absolute type pressure gauge 4, parallel moving mechanism 6, corrugated tube 7, transfiguration chamber pipeline 9, volumetric standard 10, differential pressure type pressure gauge 12 and extract system 13 are formed.
When original state, first vacuum valve 2 is in closed condition, and second vacuum valve 8, the 3rd vacuum valve 11, the 4th vacuum valve 14 all are in open mode, cuts off valve 5 and is in open mode.
Air supply system 1 links to each other with reference chamber pipeline 3 by first vacuum valve 2, and extract system 13 links to each other with reference chamber pipeline 3 by the 4th vacuum valve 14, and absolute pressure formula pressure gauge 4 links to each other with reference chamber pipeline 3; Differential pressure type pressure gauge 12 1 ends link to each other with reference chamber pipeline 3, and the other end links to each other with transfiguration chamber pipeline 9; Corrugated tube 7 one ends link to each other with parallel moving mechanism 6, and the other end links to each other with transfiguration chamber pipeline 9 by the 3rd vacuum valve 8; Volumetric standard 10 links to each other with transfiguration chamber pipeline 9 by the 4th vacuum valve 11; 3 in transfiguration chamber pipeline 9 and reference chamber pipeline link to each other by cutting off valve 5.
The course of work of this measurement mechanism is:
At first, carry out vacuum pumping by 13 pairs of corrugated tubes 7 of extract system, transfiguration chamber pipeline 9, reference chamber pipeline 3 and volumetric standard 10;
Then, close second vacuum valve 14, in the raw the time, open first vacuum valve 2, in corrugated tube 7, transfiguration chamber pipeline 9 and reference chamber pipeline 3, feed the N of certain pressure by air supply system 1 at corrugated tube 7
2Gas, its force value is measured by absolute pressure formula pressure gauge 4.
Afterwards, close and cut off valve 5, behind the balance transfiguration chamber pressure,, open first vacuum valve 1 then, N by the force value of this chamber of transfiguration constantly of differential pressure type pressure gauge 12 records
2Expand in the volumetric standard 10, after the balance, measure the force value of this chamber of transfiguration constantly by differential pressure type pressure gauge 12 once more;
Subsequently, close first vacuum valve 2, open second vacuum valve 14 and cut off valve 5, carry out vacuum pumping by 13 pairs of transfiguration chambers of extract system, reference chamber pipeline 3;
Afterwards, in the raw the time, open first vacuum valve 2, in transfiguration chamber and reference chamber pipeline 3, feed the N of certain pressure by air supply system 1 at corrugated tube
2Gas, its force value is measured by absolute pressure formula pressure gauge 4.Then, close partition valve 5, N in the balance transfiguration chamber
2Behind the pressure, by the force value of this chamber of transfiguration constantly of differential pressure type pressure gauge 12 records.Subsequently, by parallel moving mechanism 6 compress bellows 7, decrement is 8mm, produces the corrugated tube volume and changes, behind the equalized pressure, by the force value of this chamber of transfiguration constantly of differential pressure type pressure gauge 12 records.
Claims (3)
1, a kind of measurement mechanism of volume-changeable chamber bellows of constant pressure type gas flow meter volume change, it is characterized in that comprising air supply system, transfiguration chamber, cut off valve, reference chamber pipeline, absolute type pressure gauge, differential pressure type pressure gauge, parallel moving mechanism, volumetric standard, first vacuum valve, second vacuum valve, the 3rd vacuum valve, the 4th vacuum valve and extract system, wherein, the transfiguration chamber comprises corrugated tube and transfiguration chamber pipeline.
Air supply system is responsible for providing test gas;
The transfiguration chamber is used to hold gas, and wherein, corrugated tube is used for regulating the pressure of transfiguration chamber, and transfiguration chamber pipeline is used to connect corrugated tube and volumetric standard;
Cutting off valve is used for reference chamber pipeline and transfiguration chamber pipeline are separated;
The reference chamber pipeline is used to hold gas, keeps reference gas pressure constant;
The absolute type pressure gauge is used for the absolute pressure of witness mark chamber and transfiguration chamber;
The differential pressure type pressure gauge is used to write down the relative pressure that shutdown valve closes between back reference chamber pipeline and the transfiguration chamber pipeline to be changed;
Parallel moving mechanism is used at axial compression or stretching corrugated tube, and the gaseous tension that transfiguration chamber volume changes, transfiguration is indoor is changed;
Volumetric standard is used for transfiguration chamber gas and expands, and produces pressure differential, measures transfiguration chamber volume;
Extract system is responsible for finishing the vacuum pumping to reference chamber pipeline, transfiguration chamber and volumetric standard;
2, the measurement mechanism of a kind of volume-changeable chamber bellows of constant pressure type gas flow meter volume change as claimed in claim 1 is characterized in that the annexation between each ingredient is:
Air supply system links to each other with the reference chamber pipeline by first vacuum valve, and extract system links to each other with the reference chamber pipeline by second vacuum valve, and absolute pressure formula pressure gauge links to each other with the reference chamber pipeline; Differential pressure type pressure gauge one end links to each other with the reference chamber pipeline, and the other end links to each other with transfiguration chamber pipeline; Corrugated tube one end links to each other with parallel moving mechanism, and the corrugated tube other end links to each other with transfiguration chamber pipeline by the 3rd vacuum valve; Volumetric standard links to each other with transfiguration chamber pipeline by the 4th vacuum valve; Transfiguration chamber pipeline links to each other by cutting off valve with the reference chamber pipeline enclosure.
3, the measurement mechanism of a kind of volume-changeable chamber bellows of constant pressure type gas flow meter volume change as claimed in claim 1 is characterized in that the course of work is:
When original state, first vacuum valve is in closed condition, and second vacuum valve, the 3rd vacuum valve, the 4th vacuum valve all are in open mode, cuts off valve and is in open mode;
At first, by extract system corrugated tube, transfiguration chamber pipeline, reference chamber pipeline and volumetric standard are carried out vacuum pumping;
Then, close second vacuum valve, in the raw the time, open first vacuum valve, in corrugated tube, transfiguration chamber pipeline and reference chamber pipeline, feed the N of certain pressure by air supply system at corrugated tube
2Gas, its force value is drawn by the manometry of absolute pressure formula;
Afterwards, close the partition valve, behind the balance transfiguration chamber pressure, write down the force value of this transfiguration chamber in moment, open first vacuum valve then, N by the differential pressure type pressure gauge
2Expand in the volumetric standard, once more after the balance, by the force value of differential pressure type manometry transfiguration constantly chamber;
Subsequently, close first vacuum valve, open second vacuum valve and cut off valve, transfiguration chamber, reference chamber pipeline are carried out vacuum pumping by extract system;
Afterwards, in the raw the time, open first vacuum valve, in transfiguration chamber and reference chamber pipeline, feed the N of certain pressure by air supply system at corrugated tube
2Gas, its force value is drawn by the manometry of absolute pressure formula, then, closes the partition valve, N in the balance transfiguration chamber
2Behind the pressure, write down the force value of this transfiguration chamber by the differential pressure type pressure gauge in moment.Subsequently,, produce the corrugated tube volume and change, behind the equalized pressure, write down the force value of this transfiguration chamber by the differential pressure type pressure gauge in moment by the parallel moving mechanism compress bellows.
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| CNA2008101883266A CN101458109A (en) | 2008-12-22 | 2008-12-22 | Constant pressure type gas flowmeter transfiguration chamber bellows volume change measuring set |
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| CNA2008101883266A CN101458109A (en) | 2008-12-22 | 2008-12-22 | Constant pressure type gas flowmeter transfiguration chamber bellows volume change measuring set |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101709987B (en) * | 2009-12-17 | 2011-03-30 | 中国航天科技集团公司第五研究院第五一○研究所 | Device and method for measuring volume ratio of vacuum container by linear vacuometer |
| CN101672678B (en) * | 2009-10-19 | 2011-05-04 | 常州广为仪器科技有限公司 | Method and device for measuring volumes of irregular-shaped objects |
| CN102937470A (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 | Device and method for measuring container volume by using pipeline space |
| 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 |
| CN103017850A (en) * | 2012-11-27 | 2013-04-03 | 中国航天科技集团公司第五研究院第五一〇研究所 | Device and method for measuring volume ratio of vacuum container |
| CN103759785A (en) * | 2013-12-24 | 2014-04-30 | 兰州空间技术物理研究所 | Volume measurement device and method with double vacuometers for quantifying gas configuration |
| CN103791962A (en) * | 2013-12-24 | 2014-05-14 | 兰州空间技术物理研究所 | Multi-working-mode gas flowmeter and gas flow measuring method |
| CN104501914A (en) * | 2011-10-14 | 2015-04-08 | 丹尼尔测量和控制公司 | Flowmeter Calibrator And Flowmeter Calibrating Method |
| CN105784054A (en) * | 2016-03-15 | 2016-07-20 | 中国原子能科学研究院 | System and method suitable for calibrating volume of gas cavity in irregular shape |
| CN107389149A (en) * | 2017-08-07 | 2017-11-24 | 国家电网公司 | Scene operation SF6 gas insulated electric apparatus internal volume measurement apparatus and method |
| CN108168474A (en) * | 2017-12-19 | 2018-06-15 | 山东大学 | Method for detecting deep goaf volume |
| CN109030121A (en) * | 2018-07-31 | 2018-12-18 | 山西中电科新能源技术有限公司 | A kind of pair of vacuum cavity gas is sampled and meets the method, apparatus and its component of positive pressure analysis |
| CN111473833A (en) * | 2020-04-16 | 2020-07-31 | 北京东方计量测试研究所 | Vacuum cavity volume testing system and method by volume substitution method |
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2008
- 2008-12-22 CN CNA2008101883266A patent/CN101458109A/en active Pending
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101672678B (en) * | 2009-10-19 | 2011-05-04 | 常州广为仪器科技有限公司 | Method and device for measuring volumes of irregular-shaped objects |
| CN101709987B (en) * | 2009-12-17 | 2011-03-30 | 中国航天科技集团公司第五研究院第五一○研究所 | Device and method for measuring volume ratio of vacuum container by linear vacuometer |
| CN104501914A (en) * | 2011-10-14 | 2015-04-08 | 丹尼尔测量和控制公司 | Flowmeter Calibrator And Flowmeter Calibrating Method |
| CN102937470B (en) * | 2012-11-12 | 2014-05-28 | 中国航天科技集团公司第五研究院第五一〇研究所 | Device and method for measuring container volume by using pipeline space |
| CN102937470A (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 | Device and method for measuring container volume by using pipeline space |
| 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 |
| CN103017850A (en) * | 2012-11-27 | 2013-04-03 | 中国航天科技集团公司第五研究院第五一〇研究所 | Device and method for measuring volume ratio of vacuum container |
| CN103791962A (en) * | 2013-12-24 | 2014-05-14 | 兰州空间技术物理研究所 | Multi-working-mode gas flowmeter and gas flow measuring method |
| CN103759785A (en) * | 2013-12-24 | 2014-04-30 | 兰州空间技术物理研究所 | Volume measurement device and method with double vacuometers for quantifying gas configuration |
| CN103759785B (en) * | 2013-12-24 | 2017-01-04 | 兰州空间技术物理研究所 | Double vacuometer volume measurement devices and method for quantitative gas configuration |
| CN105784054A (en) * | 2016-03-15 | 2016-07-20 | 中国原子能科学研究院 | System and method suitable for calibrating volume of gas cavity in irregular shape |
| CN105784054B (en) * | 2016-03-15 | 2018-11-30 | 中国原子能科学研究院 | A kind of system and method suitable for demarcating irregular shape air cavity volume |
| CN107389149A (en) * | 2017-08-07 | 2017-11-24 | 国家电网公司 | Scene operation SF6 gas insulated electric apparatus internal volume measurement apparatus and method |
| CN107389149B (en) * | 2017-08-07 | 2023-11-10 | 国家电网公司 | Device and method for measuring internal volume of SF6 gas insulated electrical equipment in field operation |
| CN108168474A (en) * | 2017-12-19 | 2018-06-15 | 山东大学 | Method for detecting deep goaf volume |
| CN108168474B (en) * | 2017-12-19 | 2019-09-27 | 山东大学 | Method for detecting deep goaf volume |
| CN109030121A (en) * | 2018-07-31 | 2018-12-18 | 山西中电科新能源技术有限公司 | A kind of pair of vacuum cavity gas is sampled and meets the method, apparatus and its component of positive pressure analysis |
| CN111473833A (en) * | 2020-04-16 | 2020-07-31 | 北京东方计量测试研究所 | Vacuum cavity volume testing system and method by volume substitution method |
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