WO2022188308A1

WO2022188308A1 - Pressure control system and method for liquid medium for measurement accuracy testing of pressure meter

Info

Publication number: WO2022188308A1
Application number: PCT/CN2021/103596
Authority: WO
Inventors: 朱海清; 钱瑛; 沈晓东
Original assignee: 江南大学
Priority date: 2021-03-09
Filing date: 2021-06-30
Publication date: 2022-09-15
Also published as: CN113029434A; CN113029434B

Abstract

A pressure control system and method for a liquid medium for the measurement accuracy testing of a pressure meter, relating to the technical field of electromechanical integration and measurement accuracy testing of a pressure meter. The system comprises: a linear drive device, a liquid pressure adjustment device, a standard meter (12), a tested meter (13), a discharge and liquid supplementing device, a controller (8), and an operation console (11). The linear drive device is connected to the controller (8). The liquid pressure adjustment device is in power connection to the linear drive device. The discharge and liquid supplementing device is separately connected to the liquid pressure adjustment device and a liquid pipeline (14). The controller (8) is connected to the standard meter (12). The operation console (11) is communicatively connected to the controller (8) by means of a data line (10). The system can accurately control the liquid medium output by the liquid pressure adjustment device, can meet the high precision requirements for testing of low pressure to high pressure meters at the same time, and has the characteristics such as simple structure, low manufacturing cost, and high pressure control precision.

Description

Pressure control system and method of liquid medium for measuring accuracy of pressure instrument

technical field

The invention relates to the technical field of electromechanical integration and measurement accuracy detection of pressure instruments, in particular to a pressure control system and method for a liquid medium used for measurement accuracy detection of pressure instruments.

Background technique

According to the regulations, pointer-type mechanical pressure gauges, pressure transmitters, differential pressure transmitters, pressure switches, digital pressure gauges, pressure sensors, I/P controllers/positioners and other instrumentation instruments (hereinafter collectively referred to as: instruments) need to be Regular testing to ensure that the data tested can meet the required accuracy requirements; metrological testing needs to be completed in a qualified testing agency, and the instrument that passes the test will receive a metrological verification certificate issued by a qualified testing agency. Calibration certificate.

The range of the instrument is high or low, and the required pressure needs to be generated during testing. The pressure can be generated by gas (compressed air, nitrogen, etc.) or liquid (oil, water, etc.) and other media. During testing, the medium pressure needs to reach each verification point Read the reading of the instrument under test at any time to determine whether the test accuracy is qualified. Therefore, it is necessary to precisely control the medium pressure to reach the value of each verification point during the detection process, and to be able to stop and maintain the pressure.

The traditional manual pressing method not only has low work efficiency, but also has an adverse effect on the detection accuracy because it is difficult to accurately control the pressure to the pressure of each verification point at one time. For safety reasons, the automatic pressure source of gas medium can generally only provide a pressure of about 6MPa, which cannot meet the detection requirements of high pressure and ultra-high pressure instruments. However, high-pressure pressure sources such as "gas flooding liquid" also have disadvantages such as complex structure, high price, and the need for an external gas source or a pressure pump.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present invention is to overcome the problems in the prior art that the automatic pressure source has a complex structure, is expensive, and requires an external air source or a pressure pump.

In order to solve the above technical problems, the present invention provides a pressure control system for a liquid medium for measuring accuracy of a pressure instrument, including: a linear drive device, a liquid pressure regulating device, a standard meter, a detected meter, an exhaust and refilling device, a controller, an operation console; the linear driving device is connected with the controller through a first wire; the liquid pressure regulating device is dynamically connected with the linear driving device, and the liquid pressure regulating device outputs a corresponding pressure liquid medium through the linear driving device; Both the tested watch and the standard watch are connected to the output end of the liquid pressure regulating device through the liquid pipeline; The air in the liquid medium is discharged and the liquid medium is replenished; the controller is connected with the standard meter through a second wire, and the real-time pressure of the standard meter is obtained through the controller; the operation console is used to set the number of verification points and verification The pressure of the point, the operation console is connected with the controller through data line communication.

In an embodiment of the present invention, the linear drive device includes: a motor, a translation mechanism, and a telescopic shaft, the output end of the motor is connected to the translation mechanism, and the translation mechanism is used to convert the rotational motion of the motor into linear motion , the power of linear reciprocating motion is output externally by the telescopic shaft.

In an embodiment of the present invention, the liquid pressure regulating device includes: a hydraulic cylinder and a plunger, the plunger is connected to the telescopic shaft through a shaft connecting sleeve, and the reciprocating motion of the telescopic shaft makes the plunger move in the hydraulic cylinder Reciprocating motion.

In an embodiment of the present invention, the exhaust and liquid replenishment device includes: a first valve, a liquid delivery pump, a liquid storage tank, a liquid return pipe, and a second valve; one end of the liquid return pipe is connected to the hydraulic cylinder, and the other side is connected to the hydraulic cylinder. One end is connected to the liquid storage tank, the liquid pipeline is connected to the liquid storage tank through a liquid delivery pump, the first valve is set on the liquid pipeline, the second valve is set on the liquid return pipe, and the first valve It includes a one-way valve and a solenoid valve, and the second valve includes a solenoid valve.

In an embodiment of the present invention, the liquid pipeline is connected to the output end of the hydraulic cylinder, the tested gauge and the standard gauge are connected to the liquid pipeline, and the pressures of the tested gauge and the standard gauge are kept the same.

In an embodiment of the present invention, both the standard meter and the detected meter include: a pressure transmitter.

In one embodiment of the present invention, the operation console includes: a computer, a human-machine interface or a manual control knob.

In an embodiment of the present invention, the controller includes: a PLC and a single-chip microcomputer.

The present invention also provides the control method of the control system, which includes: the number of verification points and the pressure of each verification point are input to the computer or man-machine interface of the operation console in advance, the operation console sends a "start" command, and at the same time The first valve and the second valve are in a closed state; the controller receives the instruction and uploads the pressure of the standard gauge to the computer or man-machine interface of the operation console; the controller outputs the pressure and the verification point according to the current liquid medium The speed of motor rotation is controlled by the pressure difference between them, including: when the value of the pressure difference changes from large to small, the rotation speed of the motor changes from fast to slow, and when the output pressure is equal to the pressure at the verification point, the motor stops rotating; The inspection process of the test accuracy of the test table includes: controlling the motor through the controller to make the output pressure increase, pause and decrease, and pause; when the test accuracy of the test table is completed, the computer or human-machine interface of the operation console will issue a " "End" command to the controller, the controller controls the motor to stop rotating; the first valve and the second valve are opened, and the liquid delivery pump circulates the liquid medium in the liquid storage tank between the liquid pipeline, the hydraulic cylinder, and the liquid return pipe flow to remove the air from the liquid medium in the system and replenish the liquid medium.

In one embodiment of the present invention, the rotation rate of the motor is controlled by manually operating the button, so as to carry out the inspection process of the test accuracy of the tested watch.

The above-mentioned technical scheme of the present invention has the following advantages compared with the prior art:

The present invention precisely controls the output liquid medium of the liquid pressure regulating device according to the calibration point pressure preset by the operation console and the pressure rise and fall rate. The precision of the precise control can reach the micron level, and can meet the high precision of low pressure to high pressure instrument detection at the same time. In addition, it is necessary to exhaust the air of the liquid medium in the system and replenish the liquid medium in time through the exhaust and liquid replenishment device. The invention has the characteristics of simple structure, low manufacturing cost, high pressure control precision, and good cost performance.

Description of drawings

In order to make the content of the present invention easier to understand clearly, the present invention will be described in further detail below according to specific embodiments of the present invention and in conjunction with the accompanying drawings, wherein

Fig. 1 is the pressure precise control system diagram of the liquid medium used for the measurement accuracy detection of the pressure instrument of the present invention.

Description of reference signs in the manual: 1. Hydraulic cylinder; 2. Plunger; 3. Shaft connecting sleeve; 4. Telescopic shaft; 5. Translation mechanism; 6. Motor; 7. First wire; 8. Controller; 9. Data line; 10, the second lead wire; 11, the operation console; 12, the standard meter; 13, the detected meter; 14, the liquid pipeline; 15, the first valve; 16, the liquid delivery pump; 17, the liquid storage tank; 18 , return pipe; 19, the second valve.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention. It should be noted that the terms "first", "second" and the like in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances for the embodiments of the invention described herein. Furthermore, the terms "comprising" and "having", and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those expressly listed Rather, those steps or units may include other steps or units not expressly listed or inherent to these processes, methods, products or devices.

Example

Referring to Fig. 1, the pressure control system of the liquid medium for the measurement accuracy detection of the pressure instrument of the present invention includes: a linear drive device, a liquid pressure regulating device, a standard meter 12, a detected meter 13, an exhaust gas replenishment device, and a controller 8 , the operation console 11; the linear drive device and the controller 8 are connected through the first wire 7; the liquid pressure adjustment device is dynamically connected with the linear drive device, and the liquid pressure adjustment device outputs the corresponding pressure through the linear drive device The tested meter 13 and the standard meter 12 are both connected to the output end of the liquid pressure regulating device through the liquid pipeline 14; the exhaust and liquid replenishing device is respectively connected to the liquid pressure regulating device and the liquid pipeline 14 , the exhaust and rehydration device is used to discharge the air in the liquid medium and supplement the liquid medium; the controller 8 is connected with the standard meter 12 through the second wire 10 and obtains the real-time pressure of the standard meter 12 through the controller 8; The operation console 11 is used to set the number of verification points and the pressure of the verification points, and the operation console 11 and the controller 8 are connected in communication through the data line 9 . Through the above structure, the system can accurately control the output of the liquid pressure regulating device and the liquid medium according to the preset verification point pressure of the operation console 11 and the pressure rise and fall rate, and can meet the high-precision requirements of low-pressure to high-pressure instrument detection at the same time, In addition, the air of the liquid medium in the system can be exhausted and the liquid medium can be replenished in time through the exhaust and liquid replenishment device.

Specifically, the linear drive device includes: a motor 6, a translation mechanism 5, and a telescopic shaft 4. The output end of the motor 6 is connected to the translation mechanism 5, and the translation mechanism 5 is used to convert the rotational motion of the motor 6 into a straight line Movement, the power of linear reciprocating motion is externally outputted by the telescopic shaft 4; the types of the motor 6 include: servo motor, stepper motor; the translation mechanism 5 can be the following mechanism: a screw, one end of the screw is connected to the motor The other end of the screw rod is connected to the telescopic shaft 4 . Through the above-mentioned structural arrangement, the rotational motion of the motor 6 can be stably converted into a linear motion, so as to precisely control the displacement of the telescopic shaft 4 and ensure that its precision reaches the micrometer level.

Specifically, the liquid pressure regulating device includes: a hydraulic cylinder 1 and a plunger 2. The plunger 2 is connected with the telescopic shaft 4 through a shaft connecting sleeve 3, and the reciprocating motion of the telescopic shaft 4 makes the plunger 2 in the hydraulic cylinder 1 Reciprocating movement inside. Through the above structure, the pressure of the output liquid medium in the hydraulic cylinder 1 is increased or decreased.

Specifically, the exhaust and liquid replenishment device includes: a first valve 15, a liquid delivery pump 16, a liquid storage tank 17, a liquid return pipe 18, and a second valve 19; one end of the liquid return pipe 18 is connected to the hydraulic cylinder 1, The other end is connected to the liquid storage tank 17, the liquid pipeline 14 is connected to the liquid storage tank 17 through the liquid delivery pump 16, the first valve 15 is arranged on the liquid pipeline 14, and the second valve 19 is arranged on the return. On the liquid pipe 18, the first valve 15 includes a one-way valve and a solenoid valve, the second valve 19 includes a solenoid valve, and the liquid medium contained in the liquid storage tank 17 may be water or oil. Through the above structural arrangement, when the first valve 15 and the second valve 19 are in the open state, the liquid delivery pump 16 transfers the liquid medium in the liquid storage tank 17 between the liquid pipeline 14 , the hydraulic cylinder 1 and the liquid return pipe 18 . Circulating flow to discharge the air of the liquid medium in the system circuit and replenish the liquid medium.

Specifically, the liquid pipeline 14 is connected to the output end of the hydraulic cylinder 1, the detected meter 13 and the standard meter 12 are connected to the liquid pipeline 14, and the pressures of the detected meter 13 and the standard meter 12 are kept the same. The standard meter 12 transmits the pressure signal to the controller 8, which can not only accurately measure the output pressure of the liquid medium, but also provide a control feedback signal for the control of the pressure rise and fall.

Specifically, the standard table 12 and the detected table 13 both include: a pressure transmitter.

Specifically, the operation console 11 includes: a computer, a man-machine interface or a manual control knob.

Specifically, the controller 8 includes: a PLC and a single-chip microcomputer. If you choose to use manual operation to control the process of increasing, stopping, and decreasing the pressure of the liquid medium, the controller 8 does not need a PLC or a single-chip microcomputer, and the operation console 1111 only needs a manual control knob (or other similar switches) to control the motor 6 . The rotation rate (including forward and reverse, stop).

It should be noted that the pressure degree of the instrument to be tested 14 can be realized by automatic detection, and specifically can be realized by the "automatic detection device of mechanical pointer type instrument" disclosed in the application number 202010753060.6, which will not be repeated here.

This embodiment also provides a control method for the above-mentioned control system, including:

The number of verification points and the pressure of each verification point are input to the computer or human-machine interface of the operation console 11 in advance, and the operation console 11 sends the "start" command, and the first valve 15 and the second valve 19 are in a closed state at the same time. ;

The controller 8 receives the instruction and uploads the pressure of the standard meter 12 to the computer or man-machine interface of the operation console 11; the controller 8 controls the motor according to the pressure difference between the current output pressure of the liquid medium and the verification point 6. The speed of rotation (including stop), including: when the value of the pressure difference changes from large to small, the rotation rate of the motor 6 changes from fast to slow, and when the output pressure is equal to the pressure at the verification point, the motor 6 stops rotating; the above control process When the pressure difference is large, the motor 6 rotates faster, and the closer the pressure is to the verification point, the slower the motor 6 rotates. When the current output pressure is equal to the verification point pressure, the motor 6 stops rotating, so that the pressure of the liquid medium can be controlled to accurately achieve one by one verification. the pressure at the point, and achieve the required pause (pressure holding) at the pressure of each verification point.

Carry out the inspection process of the test accuracy of the detected table 13, including: controlling the motor 6 through the controller 8 to make the output pressure rise, pause and drop, pause; specifically: the controller 8 rotates according to the pre-input program, and then controls the liquid The pressure is raised, paused, lowered, and paused according to the "inspection procedures" of the pressure gauge or pressure transmitter to complete the inspection process for the test accuracy of the pressure gauge under inspection;

When the test accuracy detection process of the detected table 13 is completed, the computer or the man-machine interface of the operation console 11 sends an "end" command to the controller 8, and the controller 8 controls the motor 6 to stop rotating;

The first valve 15 and the second valve 19 are opened, and the liquid delivery pump 16 circulates the liquid medium in the liquid storage tank 17 between the liquid pipeline 14, the hydraulic cylinder 1, and the liquid return pipe 18 to circulate the liquid medium in the system. Air discharge and replenishment of liquid medium.

Further, in the above control process, the rotation rate of the motor 6 can also be controlled by manually operating the button, so as to carry out the inspection process of the test accuracy of the detected table 13 .

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For those of ordinary skill in the art, other different forms of changes or modifications can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. However, the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims

A pressure control system for a liquid medium for measuring accuracy of a pressure instrument, characterized in that it includes:

a linear drive device, the linear drive device is connected with the controller through a first wire;

a liquid pressure regulating device, the hydraulic pressure regulating device is dynamically connected with the linear driving device, and the liquid pressure regulating device outputs the liquid medium of corresponding pressure through the linear driving device;

A standard watch and a tested watch, both of the tested watch and the standard watch are connected to the output end of the liquid pressure regulating device through a liquid pipeline;

an exhaust and liquid replenishing device, which is respectively connected to the liquid pressure regulating device and the liquid pipeline, and is used for discharging the air in the liquid medium and supplementing the liquid medium;

a controller, which is connected to the standard gauge through a second wire and obtains the real-time pressure of the standard gauge through the controller;

An operation console, which is used to set the number of verification points and the pressure of the verification points, and the operation console and the controller are connected through a data line in communication.
The pressure control system of a liquid medium for measuring accuracy detection of a pressure instrument according to claim 1, wherein the linear drive device comprises: a motor, a translation mechanism, and a telescopic shaft, and the output end of the motor is connected to the translation mechanism, The translation mechanism is used to convert the rotary motion of the motor into linear motion, and the power of the linear reciprocating motion is externally outputted by the telescopic shaft.
The pressure control system for a liquid medium for measuring accuracy detection of a pressure instrument according to claim 2, wherein the liquid pressure regulating device comprises: a hydraulic cylinder and a plunger, and the plunger and the telescopic shaft are connected by a shaft connecting sleeve , Through the reciprocating motion of the telescopic shaft, the plunger reciprocates in the hydraulic cylinder.
The pressure control system for a liquid medium for detecting the measurement accuracy of a pressure instrument according to claim 2 or 3, wherein the exhaust and liquid replenishment device comprises: a first valve, a liquid delivery pump, a liquid storage tank, a liquid return pipe, The second valve; one end of the liquid return pipe is connected to the hydraulic cylinder, the other end is connected to the liquid storage tank, the liquid pipeline is connected to the liquid storage tank through a liquid delivery pump, and the first valve is arranged on the liquid pipeline, The second valve is arranged on the liquid return pipe, the first valve includes a one-way valve and a solenoid valve, and the second valve includes a solenoid valve.
The pressure control system for a liquid medium for measuring accuracy detection of a pressure instrument according to claim 3, wherein the liquid pipeline is connected to the output end of the hydraulic cylinder, and the detected meter and the standard meter are connected to the liquid pipeline And the pressure of the tested gauge and the standard gauge should be consistent.
The pressure control system for a liquid medium for measuring accuracy detection of a pressure instrument according to claim 1, wherein the standard gauge and the gauge to be detected both comprise: a pressure transmitter.
The pressure control system for a liquid medium for measuring accuracy detection of a pressure instrument according to claim 1, wherein the operation console comprises: a computer, a man-machine interface or a manual control knob.
The pressure control system for a liquid medium for measuring accuracy detection of a pressure instrument according to claim 1, wherein the controller comprises: a PLC and a single-chip microcomputer.
Utilize the control method of the described control system of claim 1-8, is characterized in that, comprises:

The number of verification points and the pressure of each verification point are input to the computer or man-machine interface of the operation console in advance, and the operation console sends a "start" command, and the first valve and the second valve are in a closed state;

The controller receives the instruction and uploads the pressure of the standard gauge to the computer or human-machine interface of the operation console; the controller controls the speed of the motor rotation according to the pressure difference between the current output pressure of the liquid medium and the verification point, Including: when the value of the pressure difference changes from large to small, the rotation rate of the motor changes from fast to slow, and when the output pressure is equal to the pressure at the verification point, the motor stops rotating;

Carry out the inspection process of the test accuracy of the tested table, including: controlling the motor through the controller to make the output pressure increase, pause and decrease, and pause;

When the test accuracy test process of the test table is completed, the computer or human-machine interface of the operation console sends an "end" command to the controller, and the controller controls the motor to stop rotating;

The first valve and the second valve are opened, and the liquid delivery pump circulates the liquid medium in the liquid storage tank between the liquid pipeline, the hydraulic cylinder and the liquid return pipe, so as to discharge the air of the liquid medium in the system and replenish the liquid medium.
The method according to claim 9, characterized in that the rotation rate of the motor is controlled by manually operating the button, so as to carry out the inspection process of the test accuracy of the detected watch.