An online mass flowmeter calibration device and a calibration method thereof

Abstract

The present application belongs to the technical field of measuring equipment, and provides an online mass flowmeter calibration device and a calibration method thereof. The method comprises switching the online running mass flowmeter from its production process pipeline to a fixed calibration loop, wherein a dynamic calibration tank with a built-in weighing module is arranged on the fixed calibration loop; medium is injected into the fixed calibration loop to complete pipeline pre-filling; the injection of medium is continued, and the cumulative value of the mass flowmeter is cleared when the indication value of the weighing module reaches a first preset weight; the injection of medium is continued until the indication value of the weighing module reaches a second preset weight, and then the injection is stopped; the actual standard mass measured by the weighing module and the cumulative indication weight generated by the mass flowmeter in the same period are synchronously obtained; the comprehensive error of the system in which the mass flowmeter is located is calculated and determined, and the calibration is completed. The present application can calibrate the mass flowmeter in situ, online and without disassembly, so as to reflect the measurement accuracy of the mass flowmeter under the real installation state and actual process conditions.

Description

Technical Field

[0001] This application relates to the field of measuring equipment technology, and in particular to an online mass flow meter calibration device and calibration method. Background Technology

[0002] Mass flow meters are frequently used in the online cigarette production process. As a core metering instrument for accurately adding key liquid materials such as sugars and flavorings, the long-term accuracy and reliability of mass flow meters directly affect the stability of product formulations, consistency of sensory quality, and control of production costs.

[0003] However, in practical applications, traditional periodic verification and calibration methods for mass flow meters have many problems: First, disassembling a mass flow meter used online from a complex process pipeline is time-consuming and labor-intensive, inevitably leading to production line interruptions and significant economic losses; second, the metrological performance of a mass flow meter is directly affected by its on-site installation conditions, such as pipeline stress, vibration, the condition of upstream and downstream straight pipe sections, and actual operating conditions, such as medium temperature, pressure, and viscosity. The idealized verification environment in the laboratory cannot reproduce these combined factors, resulting in an unavoidable deviation between the verification results and the actual on-site performance; third, each disassembly and reassembly of a mass flow meter may change its inherent installation stress and connection state, making it difficult to maintain stable indication errors before and after disassembly and reassembly, which further weakens the guiding significance of offline verification results for the accuracy of online measurement.

[0004] Current technologies offer various methods for calibrating online flow meters. For example, patent CN111174876B discloses a mobile online flow meter calibration device. The device is housed in a cabinet with casters at the bottom. The structure consists of: an outlet pipe connected to the bottom of a water tank; a gear pump, pressure gauge, electric three-way valve A, and a standard mass flow meter are sequentially installed on the outlet pipe; the end of the outlet pipe is connected to the inlet auxiliary pipe of the online flow meter via flexible hose A; a throttle valve is connected in parallel to the gear pump; the other outlet of electric three-way valve A is connected to the self-circulation return port of the water tank via a self-circulation return pipe; the outlet auxiliary pipe of the online flow meter is connected to the calibration return pipe via flexible hose B; an electric three-way valve B is installed on the calibration return pipe, and its end is connected to the calibration return port of the water tank; the other outlet of electric three-way valve B is connected to a weighing water tank via a weighing pipe; and an electronic scale rests on the bottom of the weighing water tank. This device provides both comparison and weighing calibration methods, offering high flexibility and facilitating online calibration of online flow meters. However, the calibration principle of this device involves introducing an external, movable, high-precision standard to perform isolated, comparative calibration of the flowmeter under test. This yields the flowmeter's own indication error, rather than reflecting the systematic error of the mass flowmeter under actual installation and process conditions. In other words, this device represents a calibration process completely independent of the actual production process and cannot verify the flowmeter's performance under real operating conditions.

[0005] Therefore, developing a technology and method that can perform in-situ, online calibration of mass flow meters under real working conditions without disassembling them or affecting normal production has become an urgent need for tobacco production enterprises to ensure process accuracy and improve quality control. It is also an important direction for metrology institutions to respond to industry needs and improve service efficiency, representing the inevitable trend of flow metering technology in the process industry towards real-time, on-site, and embedded diagnostics. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides an online mass flow meter calibration device and method, which can perform in-situ, online, and non-disassembly system-level calibration of the mass flow meter, thereby reflecting the measurement accuracy of the mass flow meter under actual installation conditions and actual process conditions.

[0007] To achieve the above and related objectives, the present invention adopts the following technical solution:

[0008] The first aspect of this invention provides an online mass flow meter calibration method, comprising:

[0009] The online mass flow meter is switched from its production process pipeline to a fixed calibration loop, which is equipped with a dynamic calibration tank with a built-in weighing module.

[0010] Inject the medium into the fixed calibration loop to complete the pipeline pre-filling; continue injecting the medium, and when the weighing module reading reaches the first preset weight, reset the cumulative value of the mass flow meter to zero;

[0011] Continue injecting the medium until the weighing module reading reaches the second preset weight, then stop. Simultaneously acquire the actual standard mass measured by the weighing module and the cumulative indicated weight generated by the mass flow meter at the same time.

[0012] Based on the deviation between the actual standard mass and the cumulative indicated weight, the overall error of the online automatic feeding system in which the mass flow meter is located is calculated and determined, and the calibration is completed.

[0013] Furthermore, the pipeline prefilling involves filling all connecting pipelines from the mass flow meter outlet to the dynamic calibration tank inlet with the medium and removing any gas.

[0014] Furthermore, the completion status of pipeline prefilling is determined by the first stable weight reading appearing on the weighing module.

[0015] Furthermore, the actual standard weight is the difference between the second preset weight and the first preset weight.

[0016] Furthermore, the method also includes: transporting the metered medium in the dynamic calibration tank to the downstream production process for use, and switching the mass flow meter from the fixed calibration loop back to the production process pipeline.

[0017] Furthermore, the medium is water or liquid material in an automatic feeding process.

[0018] A second aspect of the present invention provides an online mass flow meter calibration device, comprising:

[0019] The production process pipeline is equipped with a mass flow meter;

[0020] A fixed calibration loop is selectively connected to the production process pipeline through a valve group. The fixed calibration loop includes a calibration branch and a dynamic calibration tank fixed at the end of the calibration branch. A high-precision weighing module is integrated inside the dynamic calibration tank.

[0021] The control unit is connected to the valve assembly, mass flow meter, and weighing module via signals, and is configured to perform the above-described online mass flow meter calibration method.

[0022] Furthermore, it also includes storage tanks, which are connected to the production process pipelines and fixed verification circuit pipelines respectively.

[0023] Furthermore, the control unit also includes a human-machine interface.

[0024] Furthermore, it also includes a feeding pump installed on the discharge pipeline of the storage tank.

[0025] The beneficial technical effects of this invention are as follows:

[0026] This invention constructs a system-level calibration method and device by integrating a calibration loop into an online automatic feeding system and setting a dynamic calibration tank with a built-in weighing module on the calibration loop. In this invention, the entire metering and conveying path can be calibrated in the actual installation state and under actual process conditions without disassembling the mass flow meter. This achieves in-situ, online, and non-disassembly-based system-level calibration of the mass flow meter, thereby completely eliminating the impact of disassembly and the difference between laboratory and field conditions.

[0027] This invention calculates the comprehensive error of the online automatic feeding system where the mass flow meter is located by comparing the deviation between the actual standard mass and the cumulative indicated weight of the weighing module. This comprehensive error can more realistically reflect the measurement accuracy of the mass flow meter under actual installation conditions and actual process conditions.

[0028] This invention can ensure the reliability of the verification benchmark and obtain verification results with high repeatability and high reliability by pre-filling the pipeline.

[0029] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0030] The accompanying drawings, incorporated in and forming part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without inventive effort. In the drawings:

[0031] Figure 1 This is a flowchart of the verification method for this application;

[0032] Figure 2 This is a flowchart of the operation of the verification device in this application. Detailed Implementation

[0033] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should be understood that certain features of the invention (described in the context of separate embodiments for clarity) may also be provided in a single embodiment. Conversely, multiple features of the invention (described in the context of a single embodiment for brevity) may also be provided separately or in any suitable combination or, where appropriate, in any other described embodiment of the invention. Certain features described in the context of various embodiments will not be considered essential features of those embodiments unless the embodiment is inoperable without those elements. The invention is further illustrated below by specific examples; however, it should be noted that the specific process conditions and results described in the embodiments of the invention are merely illustrative and should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be covered within the scope of protection of the invention.

[0034] Please see Figure 1 The following is a flowchart of the verification method for this application, detailed below:

[0035] Step S1: Switch the online mass flow meter from its production process pipeline to the fixed calibration loop, which is equipped with a dynamic calibration tank with a built-in weighing module.

[0036] Specifically, this application initiates an online verification procedure. After completing the self-test of the online automatic feeding system, the control valve group switches the online mass flow meter from its original production process pipeline to the fixed verification loop. The weighing module is a high-precision weighing sensor.

[0037] Step S2: Inject medium into the fixed calibration loop to complete the pipeline pre-filling; continue injecting medium, and while the weighing module reading reaches the first preset weight, reset the cumulative value of the mass flow meter to zero.

[0038] Specifically, the medium in this application is water or liquid material in an automatic feeding process; the pipeline prefilling involves filling all connecting pipelines from the mass flow meter outlet to the dynamic calibration tank inlet with the medium and removing gas; and the completion status of the pipeline prefilling is determined by the first stable weight reading appearing on the weighing module, at which time the weight reading is any value lower than the first preset weight.

[0039] Step S3: Continue injecting the medium until the weighing module reading reaches the second preset weight, then stop. Simultaneously acquire the actual standard mass measured by the weighing module and the cumulative indicated weight generated by the mass flow meter during the same period.

[0040] Specifically, the actual standard mass of this application is the difference between the second preset weight and the first preset weight. The cumulative indicated weight strictly corresponds to the entire time period from the moment when the mass flowmeter is zeroed in step S2 (when the tank weight is the first preset weight) to the moment when the pump is stopped in step S3 (when the tank weight is the second preset weight).

[0041] Step S4, calculate and determine the comprehensive error of the online automatic feeding system where the mass flowmeter is located according to the deviation between the actual standard mass and the cumulative indicated weight, and complete the calibration.

[0042] Specifically, the comprehensive error of this application is as follows:

[0043] .

[0044] If the comprehensive error is positive, it indicates that the mass flowmeter may have over-measured; if the comprehensive error is negative, it indicates that the mass flowmeter may have under-measured.

[0045] Specifically, this application can set the allowable error range according to actual needs, and this range is formulated based on the requirements of the production process for metering accuracy, relevant metering regulations or the internal control standards of the enterprise. If the absolute value of the calculated comprehensive error is within the allowable error range, it is determined that this calibration is qualified and the accuracy of the current mass flowmeter is relatively accurate. If the absolute value of the calculated comprehensive error is not within the allowable error range, it is determined that this calibration is unqualified, the accuracy of the current mass flowmeter is distorted, and intervention for troubleshooting is required.

[0046] Step S5, convey the metered medium in the dynamic calibration tank to the downstream production process for utilization, and switch the mass flowmeter from the fixed calibration loop back to the production process pipeline.

[0047] This application also provides an online mass flowmeter calibration device, including: a production process pipeline, on which a mass flowmeter is installed; a fixed calibration loop, which is selectively connected to the production process pipeline through a valve group, the fixed calibration loop includes a calibration branch and a dynamic calibration tank fixedly arranged at the end of the calibration branch, and a high-precision weighing module is integrated in the dynamic calibration tank; a control unit, which is signal-connected to the valve group, the mass flowmeter and the weighing module, and is configured to execute the above online mass flowmeter calibration method.

[0048] Specifically, the production process pipeline of this application is equipped with an online mass flow meter, and components such as manual shut-off valves for isolating the mass flow meter and connecting upstream and downstream. The calibration branch can be fixedly connected to the production process pipeline by welding or flanges to form a branch pipeline, and is led out from the mass flow meter outlet, passing through the valve group and connecting to the inlet of the dynamic calibration tank. The dynamic calibration tank is located at the end of the calibration branch and is a sealed container fixedly installed on the ground or bracket. It integrates a high-precision weighing module inside, which can output the weight signal of the medium inside the tank in real time; the top of the tank has a feed port, which is connected to the calibration branch; the bottom of the tank has a discharge port, which is connected to the medium recovery or downstream process; the tank can be equipped with auxiliary components such as a level gauge, an exhaust valve, and a drain valve. The valve group of this application includes at least isolation valves installed before and after the mass flow meter, a calibration branch switching valve such as a three-way valve, and inlet and outlet valves of the dynamic calibration tank.

[0049] Specifically, this application also includes a storage tank, which is connected to the production process pipeline and the fixed verification loop pipeline, and a feeding pump installed on the discharge pipeline of the storage tank. The medium used for verification in this application can be stored in the storage tank.

[0050] Specifically, in combination Figure 2 The control unit of this application includes a human-machine interface (HMI). The operator logs in to the user management system through the HMI and selects the test mode. For example, after logging into the user management module of the online automatic feeding system's HMI, the operator switches the control mode of the electrical control cabinet to "local control, manual" mode. Then, by clicking the "Feeding Material Locally" button in the HMI, the operator enters the system's local operation interface. Next, by clicking the feeding material valve control button, the operator enters the valve manual operation interface and sets the control mode of the solenoid valve corresponding to the target storage tank to manual mode. The operator then starts the online verification program, and the control unit receives this start command.

[0051] Specifically, upon startup, the manual shut-off valves upstream and downstream of the mass flow meter are closed, and the calibration branch switching valve is opened. Simultaneously, the isolation valve on the production process pipeline closes, changing the media flow path from the original upstream process, mass flow meter, and downstream process to upstream process, mass flow meter, calibration branch, and dynamic calibration tank. At the same time, the corresponding feed valve for the storage tank is clicked on the human-machine interface, and manual opening is selected to activate the valve, injecting media into the storage tank. Once the injected media reaches the threshold preset by the system according to process requirements and the online mass flow meter's metering characteristics, the feed valve is manually closed again to stop the injection.

[0052] Specifically, once the media flow path switching is complete and confirmed, the control unit issues a command to start the feed pump, and the media is pumped from the upstream storage tank into the switched calibration loop. The media first flows through the mass flow meter, then enters the calibration branch, and finally flows to the dynamic calibration tank. During this process, the media displaces and replaces all gas in the calibration branch pipes, fittings, valves, and all cavities before the inlet of the dynamic calibration tank. This gas is then discharged through the exhaust valve installed on the tank. Once the calibration branch pipe is completely filled with media, the subsequently pumped media will continue to enter the tank, causing the tank weight to increase. Therefore, when the high-precision weighing module integrated in the dynamic calibration tank first shows a stable and continuously rising weight reading, it is determined that the pipe pre-filling is complete.

[0053] Specifically, after the pipeline pre-filling is completed, the medium continues to be injected. When the high-precision weighing module shows that the tank weight has reached the first preset weight, the cumulative value of the mass flow meter is immediately zeroed. The feed pump continues to run, maintaining a stable and controlled flow of the medium into the dynamic calibration tank. This flow rate is maintained stable by the pump frequency or regulating valve. The control unit continuously monitors the real-time reading of the high-precision weighing module on the dynamic calibration tank. When this reading accurately reaches the second preset weight set in the system, the control unit immediately issues a stop command, immediately stopping the operation of the feed pump and simultaneously closing the feed valve of the dynamic calibration tank. After the medium injection stops and the flow tends to stop, the control unit synchronously collects and records the actual standard mass and the cumulative indicated weight of the mass flow meter during the same period.

[0054] Specifically, the control unit calculates and determines the overall error of the online automatic feeding system where the mass flow meter is located based on the deviation between the actual standard mass and the cumulative indicated weight. If the absolute value of the overall error does not exceed the allowable error range, the calibration is considered successful, and the current mass flow meter is relatively accurate. If the calculated absolute value of the overall error exceeds the allowable error range, the calibration is considered unsuccessful, and the current mass flow meter is inaccurate. The mass flow meter, valves, pipelines, etc., need to be inspected and repaired, and the above calibration process must be repeated after repair.

[0055] Specifically, after calibration, close all valves on the calibration branch, switch the media flow path back to the production process pipeline, open the manual shut-off valves upstream and downstream of the mass flow meter, and restore the connection between the feed pump and the production process pipeline to ensure seamless production process continuity. Clean the media in the dynamic calibration tank. If the media is water, it can be safely discharged; if it is liquid material from the automatic feeding process, clean the residue according to regulations to ensure the tank is clean and does not affect the accuracy of the benchmark for the next calibration. At the same time, switch the control mode of the electrical control cabinet and human-machine interface from test mode to normal production mode.

[0056] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for calibrating an online mass flow meter, characterized in that, include: The online mass flow meter is switched from its production process pipeline to a fixed calibration loop, which is equipped with a dynamic calibration tank with a built-in weighing module. Inject medium into the fixed calibration circuit to complete the pipeline pre-filling; continue injecting medium, and when the weighing module reading reaches the first preset weight, clear the cumulative value of the mass flow meter; Continue injecting the medium until the weighing module reading reaches the second preset weight, then stop. Simultaneously acquire the actual standard mass measured by the weighing module and the cumulative indicated weight generated by the mass flow meter during the same period. Based on the deviation between the actual standard mass and the cumulative indicated weight, the overall error of the online automatic feeding system in which the mass flow meter is located is calculated and determined, and the calibration is completed.

2. The verification method according to claim 1, characterized in that, The pipeline prefilling involves filling all connecting pipelines from the outlet of the mass flow meter to the inlet of the dynamic calibration tank with the medium and removing the gas.

3. The verification method according to claim 2, characterized in that, The completion status of the pipeline prefilling is determined by the first stable weight reading appearing on the weighing module.

4. The verification method according to claim 1, characterized in that, The actual standard mass is the difference between the second preset weight and the first preset weight.

5. The verification method according to claim 1, characterized in that, The method further includes: transporting the metered medium in the dynamic calibration tank to the downstream production process for use, and switching the mass flow meter from the fixed calibration loop back to the production process pipeline.

6. The verification method according to claim 1, characterized in that, The medium is water or liquid material in an automatic feeding process.

7. An online mass flow meter calibration device, characterized in that, include: The production process pipeline is equipped with a mass flow meter; A fixed calibration loop is selectively connected to the production process pipeline through a valve group. The fixed calibration loop includes a calibration branch and a dynamic calibration tank fixedly installed at the end of the calibration branch. A high-precision weighing module is integrated inside the dynamic calibration tank. The control unit is signal-connected to the valve group, the mass flow meter, and the weighing module, and is configured to perform the online mass flow meter calibration method as described in any one of claims 1 to 6.

8. The verification device according to claim 7, characterized in that, It also includes a storage tank, which is connected to the production process pipeline and the fixed verification circuit pipeline, respectively.

9. The verification device according to claim 7, characterized in that, The control unit also includes a human-machine interface.

10. The verification device according to claim 8, characterized in that, It also includes a feeding pump installed on the discharge pipeline of the storage tank.

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