CN117470469A - Pressure measurement and control system and method based on gas - Google Patents
Pressure measurement and control system and method based on gas Download PDFInfo
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- CN117470469A CN117470469A CN202311435772.3A CN202311435772A CN117470469A CN 117470469 A CN117470469 A CN 117470469A CN 202311435772 A CN202311435772 A CN 202311435772A CN 117470469 A CN117470469 A CN 117470469A
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- 238000009530 blood pressure measurement Methods 0.000 title claims abstract description 20
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- 238000012360 testing method Methods 0.000 claims abstract description 26
- 230000001105 regulatory effect Effects 0.000 claims abstract description 22
- 238000005259 measurement Methods 0.000 claims abstract description 4
- 238000004146 energy storage Methods 0.000 claims description 16
- 238000001514 detection method Methods 0.000 claims description 7
- 238000004880 explosion Methods 0.000 abstract description 2
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- 101100408455 Arabidopsis thaliana PLC7 gene Proteins 0.000 description 9
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
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Abstract
The invention relates to the technical field of pressure sensor testing, in particular to a pressure measurement and control system and a measurement and control method based on gas, wherein the system comprises an electric control regulating valve, a first electromagnetic valve, a second electromagnetic valve and a product clamping seat to be tested, which are sequentially connected through a gas pipe; a third electromagnetic valve is arranged between the second electromagnetic valve and the clamping seat of the product to be tested; a first pressure sensor is arranged between the electric control regulating valve and the first electromagnetic valve; a high-pressure gas cylinder is connected to the gas pipe corresponding to the space between the first electromagnetic valve and the second electromagnetic valve; a second pressure sensor is connected to the corresponding air pipe between the third electromagnetic valve and the clamping seat of the product to be tested; the electric control regulating valve, the first electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve, the first pressure sensor and the second pressure sensor are respectively connected with a PLC, and the PLC is controlled by an upper computer. The scheme can realize the stable and accurate control of the gas pressure, is convenient for the calibration and test procedures of the pressure sensor, and can be used for measuring leakage, pressure resistance and explosion pressure by using the gas.
Description
Technical Field
The invention relates to the technical field of motor detection, in particular to a pressure measurement and control system and method based on gas.
Background
The pressure sensor is generally composed of a pressure sensitive element and a signal processing unit, is a device or a device capable of sensing pressure signals and converting the pressure signals into available output electric signals according to a certain rule, and is widely applied to various industrial self-control environments, and relates to various industries such as water conservancy and hydropower, railway transportation, intelligent building, production self-control, aerospace, military industry, petrochemical industry, oil wells, electric power, ships, machine tools, pipelines and the like.
In order to ensure that the pressure sensors projected to the market are all qualified products, before leaving the factory, manufacturers need to perform pressure test on the pressure sensors so as to analyze the performance of the corresponding pressure sensors and further screen out the qualified products.
The current calibration and test of the national pressure sensor mostly needs to purchase an imported pressure controller, and the national pressure sensor has the advantages of long purchase period, high price, high maintenance cost, incapability of being used in low-temperature and high-temperature environments, very strict control on the temperature of the controlled gas, incapability of being higher than 100 ℃, and great reduction of the service life of equipment.
Therefore, a new technical solution is urgently needed to solve the above-mentioned existing technical problems.
Disclosure of Invention
The invention aims to solve the problems of the prior art, and provides a pressure measurement and control system based on gas, which is used for solving the technical problems of high cost and harsh use environment of detection equipment caused by using imported detection equipment in the traditional method.
The above purpose is realized by the following technical scheme:
a pressure measurement and control system based on gas comprises an electric control regulating valve, a first electromagnetic valve, a second electromagnetic valve and a product clamping seat to be tested, which are sequentially connected through a gas pipe;
a third electromagnetic valve is arranged on the air pipe corresponding to the position between the second electromagnetic valve and the clamping seat of the product to be detected, an air inlet of the third electromagnetic valve is connected with the air pipe, and an air outlet of the third electromagnetic valve is communicated with the outside;
a first pressure sensor is connected to the corresponding air pipe between the electric control regulating valve and the first electromagnetic valve;
a high-pressure gas cylinder is connected to a gas pipe corresponding to the space between the first electromagnetic valve and the second electromagnetic valve;
a second pressure sensor is connected to the corresponding air pipe between the third electromagnetic valve and the clamping seat of the product to be tested;
the air inlet end of the electric control regulating valve is connected with an external pressure supply device through an air pipe;
the electric control regulating valve, the first electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve, the first pressure sensor and the second pressure sensor are respectively connected with a PLC, and the PLC is controlled by an upper computer.
Further, a safety valve is also connected to the air pipe corresponding to the position between the electric control regulating valve and the first electromagnetic valve.
Further, a pollution discharge hand valve is also connected to the high-pressure gas cylinder.
Further, the capacity of the high-pressure gas cylinder is 2L.
Further, the air pressure input by the pressure supply device is 300bar.
A measurement and control method of a pressure measurement and control system based on gas comprises the following steps:
the step (1) of building up pressure, in which the upper computer sends an instruction to control the PLC to drive the electric control regulating valve, the first electromagnetic valve and the second electromagnetic valve to be conducted, and the third electromagnetic valve to be closed, so as to form an energy storage pool, and the pressure supply device inputs air pressure into the energy storage pool to store energy for the high-pressure air cylinder;
when the first pressure sensor monitors that the air pressure in the energy storage tank reaches a preset pressure value, the feedback signal of the first pressure sensor is transmitted to the upper computer through the PLC, and the upper computer sends an instruction to control the PLC to drive the first electromagnetic valve to be closed;
step (2) a product test control device controls the PLC to drive the second electromagnetic valve to be conducted by sending an instruction, a test loop is formed among the high-pressure gas cylinder, the second electromagnetic valve and the product clamping seat to be tested, the high-pressure gas cylinder releases energy storage and transmits the energy storage to the product clamping seat to be tested, air pressure is provided for a product to be tested connected with the product clamping seat to be tested, an air pressure value in the test loop is monitored in real time through the second pressure sensor, and a feedback signal passes through the PLC to the upper computer, so that the test of the product to be tested is realized;
step (3) exhausting and resetting, and after the product to be tested is tested, the upper computer sends an instruction to control the PLC to drive the second electromagnetic valve to be closed, and control the third electromagnetic valve to be conducted, so that the air pressure in the test loop is discharged outwards; if the test is continued, the above steps are looped.
Further, the step (2) further includes the step (2-1) of detecting air leakage, if the second pressure sensor monitors that the air pressure value in the test loop drops higher than a preset safety value in real time, and a feedback signal is sent to the upper computer through the PLC; and the upper computer judges that the product to be detected is leaked, the detection result is unqualified, and sends an instruction to control the PLC to drive the second electromagnetic valve to be closed, so that the high-pressure gas cylinder is blocked, and a gas leakage alarm is sent.
Further, the preset safety value is 3bar.
Advantageous effects
According to the pressure measurement and control system based on the gas, provided by the invention, the pressure drop caused by short-time temperature reduction can be balanced by providing the high-pressure gas cylinder as energy storage, so that the output pressure is more stable; because real-time pressure control is not carried out in the test stage, a plurality of high-precision components are omitted in the internal hardware part, so that the whole system has lower cost and longer service life. And the dependence on expensive import equipment can be effectively eliminated, and the cost of manufacturers is saved.
Drawings
FIG. 1 is a schematic diagram of a pressure build-up stage of a gas-based pressure measurement and control system according to the present invention;
FIG. 2 is a schematic diagram of a product testing stage of a gas-based pressure measurement and control system according to the present invention;
FIG. 3 is a schematic diagram of a gas leakage detection stage of a gas-based pressure measurement and control system according to the present invention;
fig. 4 is a schematic diagram of an exhaust resetting stage of the gas-based pressure measurement and control system according to the present invention.
The graphic indicia:
1-electric control regulating valve, 2-first solenoid valve, 3-second solenoid valve, 4-third solenoid valve, 5-first pressure sensor, 6-second pressure sensor, 7-PLC, 8-product holder that awaits measuring, 9-high pressure gas cylinder, 10-relief valve, 11-blowdown hand valve.
Detailed Description
The invention is described in further detail below with reference to the drawings and examples. The described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1, a pressure measurement and control system based on gas comprises an electric control regulating valve 1, a first electromagnetic valve 2, a second electromagnetic valve 3 and a product clamping seat 8 to be tested, which are sequentially connected through a gas pipe;
a third electromagnetic valve 4 is arranged on an air pipe corresponding to the space between the second electromagnetic valve 3 and the product clamping seat 8 to be tested, an air inlet of the third electromagnetic valve 4 is connected with the air pipe, and an air outlet of the third electromagnetic valve 4 is communicated with the outside;
a first pressure sensor 5 is connected to the corresponding air pipe between the electric control regulating valve 1 and the first electromagnetic valve 2;
a high-pressure gas cylinder 9 is connected to the gas pipe corresponding to the space between the first electromagnetic valve 2 and the second electromagnetic valve 3;
a second pressure sensor 6 is connected to the corresponding air pipe between the third electromagnetic valve 4 and the product clamping seat 8 to be tested;
the air inlet end of the electric control regulating valve 1 is connected with an external pressure supply device through an air pipe;
the electric control regulating valve 1, the first electromagnetic valve 2, the second electromagnetic valve 3, the third electromagnetic valve 4, the first pressure sensor 5 and the second pressure sensor 6 are respectively connected with a PLC7, and the PLC7 is controlled by an upper computer.
Specifically, the electronic control regulating valve 1 in the system adopts a standard programmable electronic control proportional valve, the first electromagnetic valve 2, the second electromagnetic valve 3 and the third electromagnetic valve 4 adopt high-precision industrial pressure sensors, so that the stability and the precision control of the gas pressure are realized, and the system can be used for the calibration and test procedures of the pressure sensors and can also be used for measuring leakage, pressure resistance, explosion pressure and other scenes by using gas.
The specification of the first pressure sensor 5 in this embodiment is: 300Bar 4-20mA 0.1% FS;
the first pressure sensor 6 has the following specifications: 300bar SENT 0.02-0.05%.
As the optimization of the system, a safety valve 10 is also connected to the air pipe corresponding to the space between the electric control regulating valve 1 and the first electromagnetic valve 2, and the safety valve 10 is used for pressure relief when the air pressure in the energy storage tank is too high, so that the safety of the system is ensured.
The capacity of the high-pressure gas cylinder 9 in the system is 2L, and the 2L high-pressure gas cylinder is used as energy storage, so that the pressure drop caused by short-time temperature reduction can be balanced, the output pressure is more stable, the pressure difference between the high-precision pressure sensor 2 and a product to be detected can be eliminated, and the output precision of the pressure control equipment can be improved.
In order to facilitate the maintenance of the later-stage high-pressure gas cylinder 9, the embodiment is also connected with a blowdown hand valve 11 on the high-pressure gas cylinder 9 for cleaning the inside.
The air pressure input by the pressure supply device in this embodiment is 300bar.
In addition, the embodiment also provides a measurement and control method of the pressure measurement and control system based on gas, which comprises the following steps:
as shown in fig. 1, step (a) builds pressure, the upper computer sends an instruction to control the PLC7 to drive the electric control regulating valve 1, the first electromagnetic valve 2 and the second electromagnetic valve 3 to be conducted, controls the third electromagnetic valve 4 to be closed, forms an energy storage tank, and inputs air pressure into the energy storage tank through the pressure supply device to store energy for the high-pressure air bottle 9;
when the first pressure sensor 2 monitors that the air pressure in the energy storage tank reaches a preset pressure value, a feedback signal of the first pressure sensor 5 is transmitted to the upper computer through the PLC7, and the upper computer sends an instruction to control the PLC7 to drive the first electromagnetic valve 2 to be closed;
as shown in fig. 2, in the step (b), the product testing upper computer sends an instruction to control the PLC7 to drive the second electromagnetic valve 3 to be turned on, a testing loop is formed among the high-pressure gas cylinder 9, the second electromagnetic valve 3 and the product clamping seat 8 to be tested, the high-pressure gas cylinder 9 releases stored energy and transmits the stored energy to the product clamping seat 8 to be tested, air pressure is provided for the product to be tested connected with the product clamping seat 8 to be tested, the air pressure value in the testing loop is monitored in real time through the second pressure sensor 6, and a feedback signal is transmitted to the upper computer through the PLC7, so that the test of the product to be tested is realized;
as shown in fig. 4, after the product to be tested is tested, the upper computer sends an instruction to control the PLC7 to drive the second electromagnetic valve 3 to close, and control the third electromagnetic valve 4 to be turned on, so as to discharge the air pressure in the test loop outwards; if the test is continued, the above steps are looped.
The above steps are steps under the condition that the product to be detected is qualified, and if the product to be detected has a problem, the steps further comprise (b-1), specifically:
as shown in fig. 3, the step (b) further includes the step (b-1) of detecting air leakage if the second pressure sensor 6 monitors that the air pressure value in the test loop drops above a preset safety value in real time, and feeding back a signal to the upper computer through the PLC 7;
the upper computer judges that the product to be detected is leaked, the detection result is unqualified, and sends an instruction to control the PLC7 to drive the second electromagnetic valve 3 to be closed, so that the high-pressure gas cylinder 9 is blocked, and a gas leakage alarm is sent.
The preset safety value in this embodiment is 3bar.
The above description is for the purpose of illustrating the embodiments of the present invention and is not to be construed as limiting the invention, but is intended to cover all modifications, equivalents, improvements and alternatives falling within the spirit and principle of the invention.
Claims (8)
1. The pressure measurement and control system based on the gas is characterized by comprising an electric control regulating valve (1), a first electromagnetic valve (2), a second electromagnetic valve (3) and a product clamping seat (8) to be tested, which are sequentially connected through a gas pipe;
a third electromagnetic valve (4) is arranged on an air pipe corresponding to the space between the second electromagnetic valve (3) and the product clamping seat (8) to be tested, an air inlet of the third electromagnetic valve (4) is connected with the air pipe, and an air outlet of the third electromagnetic valve (4) is communicated with the outside;
a first pressure sensor (5) is connected to the air pipe corresponding to the position between the electric control regulating valve (1) and the first electromagnetic valve (2);
a high-pressure gas cylinder (9) is connected to the gas pipe corresponding to the space between the first electromagnetic valve (2) and the second electromagnetic valve (3);
a second pressure sensor (6) is connected to the air pipe corresponding to the space between the third electromagnetic valve (4) and the clamping seat (8) of the product to be tested;
the air inlet end of the electric control regulating valve (1) is connected with an external pressure supply device through an air pipe;
the electric control regulating valve (1), the first electromagnetic valve (2), the second electromagnetic valve (3), the third electromagnetic valve (4), the first pressure sensor (5) and the second pressure sensor (6) are respectively connected with the PLC (7), and the PLC (7) is controlled by an upper computer.
2. A gas-based pressure measurement and control system according to claim 1, characterized in that a safety valve (10) is also connected to the gas pipe between the electrically controlled regulator valve (1) and the first solenoid valve (2).
3. The pressure measurement and control system based on gas according to claim 1, characterized in that the high-pressure gas cylinder (9) is further connected with a blowdown hand valve (11).
4. A gas-based pressure measurement and control system according to claim 1, characterized in that the capacity of the high-pressure gas cylinder (9) is 2L.
5. A gas-based pressure measurement and control system according to claim 1, wherein the gas pressure input by the pressure supply device is 300bar.
6. The measurement and control method of any one of the gas-based pressure measurement and control systems according to claims 1 to 5, comprising the steps of:
step (a) building up pressure, the upper computer sends an instruction to control the PLC (7) to drive the electric control regulating valve (1), the first electromagnetic valve (2) and the second electromagnetic valve (3) to be conducted, the third electromagnetic valve (4) is controlled to be closed, an energy storage pool is formed, air pressure is input into the energy storage pool through the pressure supply device, and energy is stored in the high-pressure air bottle (9);
when the first pressure sensor (2) monitors that the air pressure in the energy storage tank reaches a preset pressure value, a feedback signal of the first pressure sensor (5) is transmitted to the upper computer through the PLC (7), and the upper computer sends an instruction to control the PLC (7) to drive the first electromagnetic valve (2) to be closed;
the method comprises the steps that (b) a product test is carried out, an upper computer sends an instruction to control a PLC (7) to drive a second electromagnetic valve (3) to be conducted, a test loop is formed among a high-pressure gas cylinder (9), the second electromagnetic valve (3) and a product clamping seat (8) to be tested, the high-pressure gas cylinder (9) releases energy storage and transmits the energy storage to the product clamping seat (8) to be tested, air pressure is provided for a product to be tested connected with the product clamping seat (8) to be tested, the air pressure value in the test loop is monitored in real time through a second pressure sensor (6), and a feedback signal is transmitted to the upper computer through the PLC (7) to realize the test of the product to be tested;
step (c) exhausting and resetting, after the product to be tested is tested, the upper computer sends an instruction to control the PLC (7) to drive the second electromagnetic valve (3) to be closed, and control the third electromagnetic valve (4) to be conducted, so that the air pressure in the test loop is discharged outwards; if the test is continued, the above steps are looped.
7. The method according to claim 6, wherein the step (b) further comprises the step (b-1) of detecting the air leakage if the second pressure sensor (6) monitors that the air pressure value in the test loop drops above a preset safety value in real time, and feeding back a signal to the upper computer through the PLC (7);
the upper computer judges that the product to be detected is leaked, the detection result is unqualified, and sends an instruction to control the PLC (7) to drive the second electromagnetic valve (3) to be closed, so that the high-pressure gas cylinder (9) is blocked, and a gas leakage alarm is sent.
8. The method of claim 7, wherein the predetermined safety value is 3bar.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311435772.3A CN117470469A (en) | 2023-11-01 | 2023-11-01 | Pressure measurement and control system and method based on gas |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311435772.3A CN117470469A (en) | 2023-11-01 | 2023-11-01 | Pressure measurement and control system and method based on gas |
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| CN117470469A true CN117470469A (en) | 2024-01-30 |
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| CN202311435772.3A Pending CN117470469A (en) | 2023-11-01 | 2023-11-01 | Pressure measurement and control system and method based on gas |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204346638U (en) * | 2014-12-12 | 2015-05-20 | 西安航天计量测试研究所 | A kind of pressure calibration/calibrating installation |
| US20200408630A1 (en) * | 2017-07-14 | 2020-12-31 | Beijing Const Instruments Technology Inc. | Pressure Calibration Apparatus And Pressure Instrument Calibration Information Processing Method |
| CN215525052U (en) * | 2021-06-15 | 2022-01-14 | 北京朗岄科技有限公司 | General check-up equipment of relief valve, manometer |
| CN114427901A (en) * | 2021-12-22 | 2022-05-03 | 青岛乾程科技股份有限公司 | System and method for realizing dynamic regulation and control and calibration of temperature and pressure of gas meter |
| CN114964758A (en) * | 2022-06-14 | 2022-08-30 | 四川长虹空调有限公司 | Portable calibration equipment of idle call pressure switch |
-
2023
- 2023-11-01 CN CN202311435772.3A patent/CN117470469A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204346638U (en) * | 2014-12-12 | 2015-05-20 | 西安航天计量测试研究所 | A kind of pressure calibration/calibrating installation |
| US20200408630A1 (en) * | 2017-07-14 | 2020-12-31 | Beijing Const Instruments Technology Inc. | Pressure Calibration Apparatus And Pressure Instrument Calibration Information Processing Method |
| CN215525052U (en) * | 2021-06-15 | 2022-01-14 | 北京朗岄科技有限公司 | General check-up equipment of relief valve, manometer |
| CN114427901A (en) * | 2021-12-22 | 2022-05-03 | 青岛乾程科技股份有限公司 | System and method for realizing dynamic regulation and control and calibration of temperature and pressure of gas meter |
| CN114964758A (en) * | 2022-06-14 | 2022-08-30 | 四川长虹空调有限公司 | Portable calibration equipment of idle call pressure switch |
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