CN210774278U - pVTt method gas flow standard device - Google Patents
pVTt method gas flow standard device Download PDFInfo
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- CN210774278U CN210774278U CN201922157044.6U CN201922157044U CN210774278U CN 210774278 U CN210774278 U CN 210774278U CN 201922157044 U CN201922157044 U CN 201922157044U CN 210774278 U CN210774278 U CN 210774278U
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Abstract
The utility model discloses a pVTt method gas flow standard device, which comprises a standard container, wherein the standard container is provided with a constant temperature guarantee component; the air inlet system comprises a detected nozzle connected with the standard container and a vacuum pump connected with the standard container, wherein a first switch valve is arranged between the standard container and the detected nozzle, and a second switch valve is arranged between the standard container and the vacuum pump; the detection system comprises a timing piece, a temperature measuring piece and a pressure measuring piece; and the pipeline system comprises a flow path pipeline for connecting the standard container, the air inlet system and the detection system. The detection system comprises a timing piece, a temperature measuring piece and a pressure measuring piece; and the pipeline system comprises a flow path pipeline for connecting the standard container, the air inlet system and the detection system. The utility model discloses device mechanism is simple reasonable effective, and it is big, the degree of accuracy is high to have detection range, has kept the measurement accuracy of pVTt method device, makes the verification time shorten greatly again.
Description
Technical Field
The utility model belongs to the technical field of the standard device and specifically relates to a pVTt method gas flow standard device.
Background
The pVTt method gas flow standard device is a widely used primary gas flow standard metering device and equipment, has high accuracy grade, the uncertainty U of measurement can reach 0.07% or higher, and is generally used as a secondary standard for tracing the measurement value of critical flow meters such as Venturi nozzles, sonic nozzles and the like. The current widely adopted primary standard devices mainly comprise bell jar type, active piston type, pVTt method and mt method gas flow standard devices and the like. In the primary standard device, the volume of a standard container of the pVTt method gas flow standard device is fixed, and parameters such as pressure, temperature and the like participating in flow calculation are measured in a static mode, so that the measurement accuracy of the device is easy to guarantee. Compared with a bell jar gas flow standard device, the pVTt method device has the advantages that the problem of low accuracy caused by high gas humidity is solved due to the fact that a liquid sealing link does not exist. At present, the unit of the multipurpose pVTt method gas flow standard device in China works under normal pressure and micro-positive pressure, and the maximum verification flow only reaches 1300m3And/h, the actual demand cannot be met. And a 0.2-level high-precision standard gas flowmeter is widely used in gas standard devices, but a scientific and legal standard device is not used for providing effective traceability, and the precision is not high and the efficiency is low.
SUMMERY OF THE UTILITY MODEL
This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments, and in this section as well as in the abstract of the specification and the title of the application may be somewhat simplified or omitted to avoid obscuring the purpose of this section, the abstract of the specification and the title of the application, and such simplification or omission may not be used to limit the scope of the invention.
The present invention has been made in view of the above and/or other problems occurring in the prior art.
Therefore, the utility model aims to solve the technical problem that the precision is not high, efficiency is low excessively when current multipurpose pVTt method gas flow standard device tests.
In order to solve the technical problem, the utility model provides a following technical scheme: a pVTt method gas flow standard device comprises a standard container, a temperature constant guarantee component and a temperature constant guarantee component, wherein the standard container is provided with the temperature constant guarantee component; the air inlet system comprises a detected nozzle connected with the standard container and a vacuum pump connected with the standard container, wherein a first switch valve is arranged between the standard container and the detected nozzle, and a second switch valve is arranged between the standard container and the vacuum pump; the detection system comprises a timing piece, a temperature measuring piece and a pressure measuring piece; the pipeline system comprises a flow path pipeline for connecting the standard container, the air inlet system and the detection system.
As a preferred scheme of pVTt method gas flow standard device, wherein: the pipeline system comprises a first pipeline, a second pipeline, a third pipeline, a fourth pipeline and a fifth pipeline.
As a preferred scheme of pVTt method gas flow standard device, wherein: the first switch valve is arranged on the first pipeline, one end of the first pipeline is connected to the detected nozzle, and the other end of the first pipeline is connected to the standard container; the second switch valve is arranged on the second pipeline, one end of the second pipeline is connected to the vacuum pump, and the other end of the second pipeline is connected to the standard container.
As a preferred scheme of pVTt method gas flow standard device, wherein: the timing piece is arranged on the third pipeline, one end of the third pipeline is connected to the first switch valve, and the other end of the third pipeline is connected to the timing piece. The temperature measuring piece is arranged on the fourth pipeline, one end of the fourth pipeline is connected with the temperature measuring piece, and the other end of the fourth pipeline is connected with the standard container. The pressure measuring and pressing piece is arranged on the fifth pipeline, one end of the fifth pipeline is connected with the pressure measuring and pressing piece, and the other end of the fifth pipeline is connected with the standard container.
As a preferred scheme of pVTt method gas flow standard device, wherein: the detection system further comprises an optical-electrical signal converter, the optical-electrical signal converter is arranged on the third pipeline, and the optical-electrical signal converter is located between the first switch valve and the timing piece.
As a preferred scheme of pVTt method gas flow standard device, wherein: the detection system further comprises an upper computer, and the timing piece, the temperature measuring piece and the pressure measuring piece are connected to the upper computer.
As a preferred scheme of pVTt method gas flow standard device, wherein: the standard container is provided with an air inlet and an air extraction opening, the air inlet is connected with the detected nozzle through the first pipeline, and the air extraction opening is connected with the vacuum pump through the second pipeline.
As a preferred scheme of pVTt method gas flow standard device, wherein: the constant guarantee assembly is a constant-temperature water bath jacket.
As a preferred scheme of pVTt method gas flow standard device, wherein: the temperature measuring part is a temperature sensor, and the pressure measuring part is a pressure sensor.
The utility model has the advantages that: the device provided by the invention has the advantages of simple, reasonable and effective mechanism, large detection range and high accuracy, keeps the measurement accuracy of the pVTt method device, and greatly shortens the verification time.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor. Wherein:
fig. 1 is a schematic diagram illustrating a principle of a pVTt method gas flow calibration apparatus according to a first embodiment of the present invention;
fig. 2 is a schematic diagram of the principle of a pVTt method gas flow calibration apparatus according to a second embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a pVTt method gas flow rate calibration apparatus according to a second embodiment of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, embodiments accompanying the present invention are described in detail below with reference to the accompanying drawings.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be implemented in other ways different from the specific details set forth herein, and one skilled in the art may similarly generalize the present invention without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.
Next, the present invention will be described in detail with reference to the schematic drawings, and in the detailed description of the embodiments of the present invention, for convenience of illustration, the sectional view showing the device structure will not be enlarged partially according to the general scale, and the schematic drawings are only examples, and should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.
Further still, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with at least one implementation of the invention is included. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.
Example 1
Referring to fig. 1, the embodiment provides a pVTt method gas flow rate calibration apparatus, including a calibration container 100, the calibration container 100 is configured with a temperature constant guarantee component 101; an air intake system 200 including a nozzle 201 to be inspected connected to the standard container 100 and a vacuum pump 202 connected to the standard container 100, wherein a first on-off valve 203 is provided between the standard container 100 and the nozzle 201 to be inspected, and a second on-off valve 204 is provided between the standard container 100 and the vacuum pump 202; the detection system 300 comprises a timing piece 301, a temperature measuring piece 302 and a pressure measuring piece 303; and a piping system 400 including a flow path piping for connecting between the standard container 100, the air intake system 200, and the detection system 300. The detection system 300 comprises a timing piece 301, a temperature measuring piece 302 and a pressure measuring piece 303; and a piping system 400 including a flow path piping for connecting between the standard container 100, the air intake system 200, and the detection system 300.
The standard container 100 adopts the existing integral skid-mounted structure, and the skid-mounted structure is an integrated mode that functional components are integrated on an integral base and can be integrally mounted and moved; the skid mounting is conveniently carried out by moving and positioning the equipment by using a skid bar, and comprises a verification station which is correspondingly arranged with the standard container 100, and the standard container 100 is provided with a constant temperature guaranteeing assembly 101, wherein the constant temperature guaranteeing assembly 101 adopts a water jacket type constant temperature setting in the prior art and is used for controlling the temperature of the periphery of the standard container 100.
Preferably, a constant temperature guaranteeing assembly 101 is arranged outside the standard container 100, and the constant temperature guaranteeing assembly 101 is a constant temperature water bath device, so that the outer surface of the standard container 100 is kept at a constant temperature. Since the temperature measuring points are scientifically distributed at multiple points in the standard container 100, in a 34m standard container, each cubic meter is not less than 1 temperature measuring point, and the total number of the temperature measuring points is not less than 40 temperature measuring points, when the standard container is 3m, the number of the temperature measuring points is not less than 8, the number of the temperature measuring points is 0.1m, and the number of the temperature measuring points is not less than 4, so that the measurement uncertainty caused by the non-uniform temperature of the gas in the standard container is reduced, in the embodiment, 42 temperature sensors are distributed in the standard container 100.
Further, the pipe system 400 includes a first pipe 401, a second pipe 402, a third pipe 403, a fourth pipe 404, and a fifth pipe 405. The first on-off valve 203 is arranged on a first pipeline 401, one end of the first pipeline 401 is connected to the detected nozzle 201, and the other end is connected to the standard container 100; the second on-off valve 204 is disposed on a second pipe 402, and one end of the second pipe 402 is connected to the vacuum pump 202, and the other end is connected to the standard container 100.
Further, the timing member 301 is provided on a third pipe 403, and one end of the third pipe 403 is connected to the first switching valve 203 and the other end is connected to the timing member 301. The temperature measuring member 302 is disposed on the fourth pipeline 404, one end of the fourth pipeline 404 is connected to the temperature measuring member 302, and the other end is connected to the standard container 100. The pressure measuring component 303 is arranged on a fifth pipeline 405, one end of the fifth pipeline 405 is connected with the pressure measuring component 303, and the other end is connected with the standard container 100.
Preferably, the temperature measuring component 302 is a temperature sensor, and the pressure measuring component 303 is a pressure sensor. After the sensor collects the measurement data, the corresponding detected numerical value is displayed on the temperature value and pressure value display instrument.
The detection system 300 further comprises an optical-to-electrical signal converter 304, the optical-to-electrical signal converter 304 being arranged on the third pipe 403, the optical-to-electrical signal converter 304 being located between the first on-off valve 203 and the timing member 301. The photoelectric signal converter 304 transmits data of the first switching valve 203 to the timer 301.
The pre-aeration equilibrium state parameters and the in-tank gas parameters five minutes after aeration and the water bath temperature in the standard vessel 100 were measured. And (3) establishing a prediction model of temperature difference, pressure and temperature by adopting big data processing on the temperature difference between the average temperature of the gas in the tank body and the water bath temperature measured five minutes after air inlet and the pressure data in the tank body, and calculating the detection mass flow of the device by predicting the values of the pressure and the temperature in the tank body in a steady state and using a related formula.
Example 2
Referring to fig. 3, a second embodiment of the present invention is based on the previous embodiment, and is different from the previous embodiment in that: the detection system 300 further comprises an upper computer 305, a timing piece 301, a temperature measuring piece 302 and a pressure measuring piece 303 which are all connected to the upper computer 305.
Specifically, the invention comprises a standard container 100, wherein the standard container 100 is provided with a constant temperature guarantee assembly 101; an air intake system 200 including a nozzle 201 to be inspected connected to the standard container 100 and a vacuum pump 202 connected to the standard container 100, wherein a first on-off valve 203 is provided between the standard container 100 and the nozzle 201 to be inspected, and a second on-off valve 204 is provided between the standard container 100 and the vacuum pump 202; the detection system 300 comprises a timing piece 301, a temperature measuring piece 302 and a pressure measuring piece 303; and a piping system 400 including a flow path piping for connecting between the standard container 100, the air intake system 200, and the detection system 300. The detection system 300 comprises a timing piece 301, a temperature measuring piece 302 and a pressure measuring piece 303; and a piping system 400 including a flow path piping for connecting between the standard container 100, the air intake system 200, and the detection system 300.
Further, the pipe system 400 includes a first pipe 401, a second pipe 402, a third pipe 403, a fourth pipe 404, and a fifth pipe 405. The first on-off valve 203 is arranged on a first pipeline 401, one end of the first pipeline 401 is connected to the detected nozzle 201, and the other end is connected to the standard container 100; the second on-off valve 204 is disposed on a second pipe 402, and one end of the second pipe 402 is connected to the vacuum pump 202, and the other end is connected to the standard container 100.
Further, the timing member 301 is provided on a third pipe 403, and one end of the third pipe 403 is connected to the first switching valve 203 and the other end is connected to the timing member 301. The temperature measuring member 302 is disposed on the fourth pipeline 404, one end of the fourth pipeline 404 is connected to the temperature measuring member 302, and the other end is connected to the standard container 100. The pressure measuring component 303 is arranged on a fifth pipeline 405, one end of the fifth pipeline 405 is connected with the pressure measuring component 303, and the other end is connected with the standard container 100.
Preferably, the temperature measuring component 302 is a temperature sensor, and the pressure measuring component 303 is a pressure sensor. After the sensor collects the measurement data, the corresponding detected numerical value is displayed on the temperature value and pressure value display instrument.
The detection system 300 further comprises an optical-to-electrical signal converter 304, the optical-to-electrical signal converter 304 being arranged on the third pipe 403, the optical-to-electrical signal converter 304 being located between the first on-off valve 203 and the timing member 301. The photoelectric signal converter 304 transmits data of the first switching valve 203 to the timer 301.
After data are collected, the data of the timing part 301, the temperature measuring part 302 and the pressure measuring part 303 are all transmitted to the upper computer 305, a prediction model of temperature difference, pressure and temperature is established for the temperature difference between the average temperature of gas in the tank body and the water bath temperature measured five minutes after air inlet and the pressure data in the tank body by adopting big data processing, and the detection mass flow of the device can be calculated by predicting the values of the pressure and the temperature in the tank body in a steady state and utilizing a correlation formula.
The utility model discloses specific theory of operation specifically as follows:
before the calibration is started, the standard container 100 is selected according to the flow rate, the second on-off valve 204 is opened, the standard container 100 is vacuumed by the vacuum pump 202, and the second on-off valve 204 is closed. According to the temperature and pressure of the standard container 100 measured by the above sensors when the vacuum is applied, the temperature constant guarantee assembly 101 adjusts the temperature of the standard container 100 to be stabilized, and measures the temperature and pressure of the gas in the standard container 100 after the temperature of the gas in the standard container 100 is stabilized.
The first on-off valve 203 is opened, and the timer 301 is started to time. The atmospheric air passes through the test nozzle 201 and the first on-off valve 203, and the air continues to flow into the standard container 100 at a constant flow rate. After the standard container 100 is full, the first switch valve 203 is closed, and the timer 301 is stopped. And at the same time, the temperature inside the standard container 100 is regulated and stabilized again by using the constant temperature guarantee assembly 101, and the temperature and the pressure of the gas inside the standard container 100 are measured after the temperature of the gas inside the standard container 100 is stabilized. The theoretical mass flow through the inspected nozzle 201 can be measured.
It is important to note that the construction and arrangement of the present application as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperatures, pressures, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in this application. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of this invention. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present inventions. Therefore, the present invention is not limited to a particular embodiment, but extends to various modifications that nevertheless fall within the scope of the appended claims.
Moreover, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not be described (i.e., those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the invention).
It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.
It should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the scope of the claims of the present invention.
Claims (9)
1. A pVTt method gas flow standard device which characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,
a standard container (100), the standard container (100) being provided with a constant temperature guarantee assembly (101);
the air inlet system (200) comprises a detected nozzle (201) connected with the standard container (100) and a vacuum pump (202) connected with the standard container (100), wherein a first switch valve (203) is arranged between the standard container (100) and the detected nozzle (201), and a second switch valve (204) is arranged between the standard container (100) and the vacuum pump (202);
the detection system (300) comprises a timing piece (301), a temperature measuring piece (302) and a pressure measuring piece (303); and the number of the first and second groups,
a piping system (400) comprising a flow path piping for connecting between the standard container (100), the air intake system (200), and the detection system (300).
2. The pVTt method gas flow calibration apparatus of claim 1, wherein: the pipe system (400) comprises a first pipe (401), a second pipe (402), a third pipe (403), a fourth pipe (404) and a fifth pipe (405).
3. The pVTt method gas flow calibration apparatus of claim 2, wherein: the first switch valve (203) is arranged on the first pipeline (401), one end of the first pipeline (401) is connected to the tested nozzle (201), and the other end of the first pipeline is connected to the standard container (100);
the second switch valve (204) is arranged on the second pipeline (402), one end of the second pipeline (402) is connected to the vacuum pump (202), and the other end of the second pipeline is connected to the standard container (100).
4. The pVTt method gas flow calibration device according to claim 3, wherein: the timing piece (301) is arranged on the third pipeline (403), one end of the third pipeline (403) is connected to the first switch valve (203), and the other end of the third pipeline is connected to the timing piece (301);
the temperature measuring piece (302) is arranged on the fourth pipeline (404), one end of the fourth pipeline (404) is connected with the temperature measuring piece (302), and the other end of the fourth pipeline (404) is connected with the standard container (100);
the pressure measuring and pressing piece (303) is arranged on the fifth pipeline (405), one end of the fifth pipeline (405) is connected with the pressure measuring and pressing piece (303), and the other end of the fifth pipeline is connected with the standard container (100).
5. The pVTt method gas flow calibration device according to claim 4, wherein: the detection system (300) further comprises an optoelectronic signal converter (304), the optoelectronic signal converter (304) being arranged on the third pipeline (403), the optoelectronic signal converter (304) being located between the first on-off valve (203) and the timing member (301).
6. The pVTt method gas flow rate standard device according to any one of claims 1 to 5, wherein: the detection system (300) further comprises an upper computer (305), and the timing piece (301), the temperature measuring piece (302) and the pressure measuring piece (303) are connected to the upper computer (305).
7. The pVTt method gas flow rate standard device according to any one of claims 2 to 5, wherein: the standard container (100) is provided with an air inlet (100a) and an air extraction opening (100b), the air inlet (100a) is connected with the detected nozzle (201) through the first pipeline (401), and the air extraction opening (100b) is connected with the vacuum pump (202) through the second pipeline (402).
8. The pVTt method gas flow calibration device according to claim 7, wherein: the constant guarantee assembly (101) is a constant-temperature water bath jacket.
9. The pVTt method gas flow calibration apparatus of claim 8, wherein: the temperature measuring piece (302) is a temperature sensor, and the pressure measuring piece (303) is a pressure sensor.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201922157044.6U CN210774278U (en) | 2019-12-05 | 2019-12-05 | pVTt method gas flow standard device |
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| CN201922157044.6U CN210774278U (en) | 2019-12-05 | 2019-12-05 | pVTt method gas flow standard device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112067087A (en) * | 2020-08-13 | 2020-12-11 | 镇江市计量检定测试中心 | Gas flow standard device capable of adjusting centering of sonic nozzle |
| CN112067086A (en) * | 2020-08-11 | 2020-12-11 | 镇江市计量检定测试中心 | Jar internal temperature field measurement system of large-scale pVTt metering tank |
-
2019
- 2019-12-05 CN CN201922157044.6U patent/CN210774278U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112067086A (en) * | 2020-08-11 | 2020-12-11 | 镇江市计量检定测试中心 | Jar internal temperature field measurement system of large-scale pVTt metering tank |
| CN112067086B (en) * | 2020-08-11 | 2021-04-13 | 镇江市计量检定测试中心 | Jar internal temperature field measurement system of large-scale pVTt metering tank |
| CN112067087A (en) * | 2020-08-13 | 2020-12-11 | 镇江市计量检定测试中心 | Gas flow standard device capable of adjusting centering of sonic nozzle |
| CN112067087B (en) * | 2020-08-13 | 2021-04-13 | 镇江市计量检定测试中心 | Gas flow standard device capable of adjusting centering of sonic nozzle |
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