High-viscosity fluid precision metering system and implementation method

Abstract

The high-viscosity fluid precision metering system comprises an electric control module, the electric control module is connected with a self-calibration module, a temperature compensation module, a power conveying module and a sensing module, and the temperature compensation module, the power conveying module and the sensing module are all installed on a pipeline where high-viscosity fluid flows. An inlet of the pipeline is provided with a feeding electric one-way valve, and an outlet of the pipeline is provided with a discharging electric one-way valve. The method has the following advantages that the influence of parameter changes of fluid temperature, pressure, viscosity, density and the like on the metering precision is eliminated through self-calibration and algorithm optimization, the problems of retention and blockage are solved through viscosity adjustment, the ultrasonic non-contact disassembly sensor is adopted, the influence of the fluid flow speed is avoided, and high-precision, high-stability and high-speed liquid conveying and metering are achieved.

Description

Technical Field

[0001] The present invention is a high-viscosity fluid precision metering system, belonging to the technical field of flow metering. Background Art

[0002] High-viscosity fluids are very widely used in application fields such as chemical engineering, food, medicine, petroleum, environmental protection, and construction. For example: In the chemical engineering field: rubber, asphalt, epoxy resin, adhesives, high-temperature molten polymers; In the food field: syrup, honey, chocolate paste, milk, juice and other high-viscosity food raw materials; In the medical field: collagen, gel-like medical materials; In the petroleum field: crude oil and lubricating oil: high-viscosity crude oil, heavy oil, lubricating oil; In the environmental protection field: sludge and waste liquid: sewage sludge containing solid particles, industrial waste liquid (such as oil-containing sludge); In the building materials field: clay, cement additives and other high-viscosity building materials.

[0003] Metering is to count the quantity of fluids, and the transportation of fluids is inseparable from metering; due to the special physical properties of high-viscosity fluids, compared with conventional viscosity fluids, their metering faces many technical challenges in industrial applications: Due to the relatively high viscosity of high-viscosity fluids, their flow states are complex, and they are prone to form blockages in the flowmeter, resulting in inaccurate measurements or even equipment damage; The fluidity of high-viscosity fluids is poor, and it is easy to form stagnation inside the flowmeter and adhere to the inner wall of the pipeline or pump body, affecting the stability and accuracy of measurement.

[0004] High-viscosity fluids are sensitive to temperature, and the viscosity changes significantly with temperature (for example, when the temperature of asphalt increases by 10°C, the viscosity can be reduced by 50%), resulting in changes in the fluid transportation pressure and affecting the metering accuracy.

[0005] The difficulties in the high-viscosity fluid metering industry have caused application pain points in many industries. For example: Asphalt paving: Temperature fluctuations cause unstable pump delivery flow, resulting in uneven paving thickness; Food industry: The metering of chocolate coatings leads to overweight differences in products due to viscosity changes; Pharmaceutical filling: High-precision filling of syrup-like drugs is required, but residual wall sticking affects dose consistency; Electronic packaging: Epoxy resin dispensing requires milligram-level precision, but the thixotropy of the fluid causes sudden flow changes during start-stop stages.

[0006] Traditional high-viscosity fluid metering mostly uses screw pumps, piston pumps, etc. to drive the flow of high-viscosity fluids, flowing through a flowmeter with a mechanical counter. The fluid drives the rotor inside the flowmeter to rotate, and the volume of the fluid is measured by calculating the number of rotations of the rotor. However, this method has the following disadvantages: (1)The change of fluid parameters affects the metering accuracy: The changes of fluid parameters such as temperature, pressure, viscosity, and density have an impact on the metering accuracy. For example, the change of viscosity causes low metering accuracy: The viscosity of high-viscosity fluids changes with temperature and batch. The force on the rotor inside the flowmeter changes, and the metering accuracy drops significantly; The change of flow velocity causes the deviation of metering accuracy: The thixotropy of high-viscosity fluids. When fluids with different flow velocities of the same volume pass through the flowmeter, the force on the rotor inside the flowmeter changes, resulting in inaccurate metering; (2)It cannot meter ultra-high viscosity fluids: Ultra-high viscosity fluids are prone to form retention and blockage inside the flowmeter; (3)The flow velocity affects the metering accuracy: When the fluid flow velocity is too high, the rotational speed of the rotor inside the flowmeter will reach the limit, which has an impact on the metering accuracy. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a high-viscosity fluid precision metering system aiming at the above deficiencies. Through self-calibration and algorithm optimization, the influence of the changes of fluid parameters such as temperature, pressure, viscosity, and density on the metering accuracy is eliminated. The retention and blockage problems are solved through viscosity adjustment. An ultrasonic non-contact sensor is adopted, which is not affected by the fluid flow velocity, and high-precision, high-stability, and high-speed liquid transportation and metering are realized.

[0008] To solve the above technical problems, the present invention adopts the following technical solutions: A high-viscosity fluid precision metering system includes an electronic control module, which is connected with a self-calibration module, a temperature compensation module, a power transmission module, and a sensing module. The temperature compensation module, the power transmission module, and the sensing module are all installed on the pipeline where the high-viscosity fluid flows. An inlet feed electric check valve is provided at the inlet of the pipeline, and an outlet discharge electric check valve is provided at the outlet of the pipeline; The power transmission module includes a gear pump, the gear pump is connected with a variable frequency speed regulator, the power transmission module is connected with the temperature compensation module, and the fluid whose viscosity is adjusted by the temperature compensation module is driven by the gear pump with variable frequency speed regulation; The self-calibration module includes a sampling cylinder. An electronic scale S5 is provided at the bottom of the sampling cylinder. The sampling cylinder is connected with a sampling feed pipeline, a sampling discharge pipeline, and a pressurizing pipeline. The sampling feed pipeline is connected to the feed point of the pipeline where the high-viscosity fluid flows, and the sampling discharge pipeline is connected to the discharge point of the pipeline where the high-viscosity fluid flows. A No. 2 self-calibration electric check valve is provided on the sampling feed pipeline, and a No. 1 self-calibration electric check valve is provided on the sampling discharge pipeline. The pressurizing pipeline is used to input compressed air into the sampling cylinder, and a compressed air solenoid valve is provided on the pressurizing pipeline.

[0009] Further, the electric control module includes a PLC and a power supply. One end of the positive pole of the power supply is connected to one end of a stop button K1, the other end of the stop button K1 is connected to one end of a start button K2 and one end of a self-holding contact of a main relay KM1, the other end of the start button K2 and the other end of the self-holding contact of the main relay KM1 are connected to one end of a coil of the main relay KM1 and one end of a main contact of the main relay KM1, and the other end of the coil of the main relay KM1 is connected to the negative pole of the power supply.

[0010] Further, the other end of the main contact of the main relay KM1 is connected to a PLC, a temperature compensation module, one end of a coil of a feed electric check valve KS1, one end of a frequency converter SQ, one end of a temperature sensor S1, one end of a pressure sensor S2, one end of a viscosity sensor S3, one end of an ultrasonic speed measurement sensor S4, one end of an electronic scale S5, and one end of an electronic density meter S6. The other end of the coil of the feed electric check valve KS1, the other end of the frequency converter SQ, the other end of the temperature sensor S1, the other end of the pressure sensor S2, the other end of the viscosity sensor S3, the other end of the ultrasonic speed measurement sensor S4, the other end of the electronic scale S5, and the other end of the electronic density meter S6 are connected to the negative pole of the power supply.

[0011] Further, the signal output terminal OUT1 of the temperature sensor S1 is connected to the input terminal IN1 of the PLC, the signal output terminal OUT2 of the pressure sensor S2 is connected to the input terminal IN2 of the PLC, the signal output terminal OUT3 of the viscosity sensor S3 is connected to the input terminal IN3 of the PLC, the signal output terminal OUT4 of the ultrasonic speed measurement sensor S4 is connected to the input terminal IN4 of the PLC, the signal output terminal OUT5 of the electronic scale S5 is connected to the input terminal IN5 of the PLC, and the signal output terminal OUT6 of the electronic density meter S6 is connected to the input terminal IN6 of the PLC.

[0012] Further, the PLC is connected to one end of a coil of a 1# self-calibration electric check valve KS2, one end of a coil of a 2# self-calibration electric check valve KS3, one end of a coil of a compressed air solenoid valve KS4, and one end of a coil of a discharge electric check valve KS5. The other end of the coil of the 1# self-calibration electric check valve KS2, the other end of the coil of the 2# self-calibration electric check valve KS3, the other end of the coil of the compressed air solenoid valve KS4, and the other end of the coil of the discharge electric check valve KS5 are connected to the negative pole of the power supply.

[0013] A method for realizing a high-viscosity fluid precision metering system includes the following steps: Step 1. Execute self-calibration internal circulation: Press the start button, the coil of the main relay is energized and self-held, the main contact of the main relay closes, and the feed electric check valve opens; The PLC controls the discharge electric check valve to close, the 1# self-calibration check valve opens, the 2# self-calibration check valve opens, and the high-viscosity fluid enters the pipeline through the feed electric check valve; The high-viscosity fluid flows through the temperature compensation module, gear pump, ultrasonic velocity sensor S4, 1# self-calibrating one-way electric valve, self-calibration module, and 2# self-calibrating one-way electric valve. Then, the high-viscosity fluid enters the temperature compensation module again for internal circulation; Step 2. System external circulation: The PLC controls the closing of the 1# self-calibrating one-way electric valve and the 2# self-calibrating one-way electric valve, and opens the discharge electric one-way valve, causing the fluid to switch from internal circulation to external circulation; The high-viscosity fluid enters the pipeline through the feed electric one-way valve, flows through the temperature compensation module, gear pump, ultrasonic velocity sensor S4, and discharges through the discharge electric one-way valve; By monitoring the flow velocity data obtained by the ultrasonic velocity sensor S4, the fluid metering reference data FL_1 can be obtained. Through the calibration proportionality coefficient K, the true flow rate of the fluid can be obtained ; Step 3. Construct the system adaptive big data model: Since the calibration proportionality coefficient K is related to the temperature T, pressure P, viscosity D, and density q, establish a data correlation model for the proportionality factors of each parameter: K = T * k1 + P * k2 + D * k3 + q * k4; Where k1 is the temperature proportionality factor, k2 is the pressure proportionality factor, k3 is the viscosity proportionality factor, and k4 is the density proportionality factor; Through big data analysis and self-learning, draw the relationship curves between each parameter and the proportionality factor. In this way, when changing products or process parameters, there is no need for self-calibration again. Through the relationship curves between each parameter and the proportionality factor, the corresponding proportionality factor values of k1, k2, k3, and k4 can be quickly obtained according to the data of each sensor. Through the formula K = T * k1 + P * k2 + D * k3 + q * k4, the calibration proportionality coefficient K can be obtained. By multiplying the calibration proportionality coefficient K by the flow rate data of the ultrasonic velocity sensor S4, the true and accurate metering data can be obtained.

[0014] Furthermore, step 1 specifically includes the following steps: Step 1.1: Temperature compensation to adjust the fluid viscosity; The high-viscosity fluid has very poor fluidity. The temperature compensation module heats the high-viscosity fluid to 50 - 80 °C to increase its fluidity and make its viscosity value between 15000 - 30000 centipoises; The temperature sensor S1 and viscosity sensor S3 obtain the temperature and viscosity values and send the data to the electronic control module; Step 1.2: Variable frequency speed regulation to adjust the fluid flow rate; The variable frequency speed regulator of the power transmission module drives the gear pump to operate, and the high-viscosity fluid is transmitted in the pipeline at a certain flow rate. To adapt to different delivery volumes, the flow rate of the high-viscosity fluid in the pipeline is adjusted by increasing or decreasing the output frequency of the variable frequency speed regulator; The ultrasonic velocity sensor S4 monitors the velocity value of the fluid in the pipeline and sends the data to the electronic control module; Step 1.3: Measurement calibration; Theoretically, the fluid velocity can be obtained by using the ultrasonic velocity sensor S4 on the outer wall of the pipe and multiplied by the cross-sectional area of the pipe to obtain the fluid flow rate. In actual situations, the temperature, pressure, viscosity and density of the fluid in the pipe will affect the electrical signal data of ultrasonic detection and reduce the accuracy of the detection data, so measurement calibration is required.

[0015] Furthermore, the metrological calibration comprises the following steps: Step 1.3.1 Obtain the fluid parameter data in the pipeline; The temperature sensor S1 obtains the temperature data T, the pressure sensor S2 obtains the pressure data P, the viscosity sensor S3 obtains the viscosity data D, and the ultrasonic velocity sensor S4 obtains the flow rate data V. The calibration of the measurement needs to be carried out under a stable parameter environment. When the fluctuation of the above data is less than 1%, proceed to the next step; Step 1.3.2 Calculate fluid measurement reference data; According to the flow velocity data V obtained by the ultrasonic velocity sensor S4, multiplied by the pipe cross-sectional area S, the fluid metering reference data FL_1=V*S can be obtained; Step 1.3.3 Self-calibration, calculate the proportionality coefficient between the fluid measurement reference data and the true value; High viscosity fluid can flow into the sampling cylinder multiple times, and the weight data can be obtained by weighing multiple times until the liquid level of the sampling cylinder reaches the upper limit, and then the sampling cylinder is emptied, and then it flows in again and weighed, and the cycle continues; Within the unit sampling time △t, the high viscosity fluid flows into the sampling tube through the 1# self-calibration one-way electric valve. The electronic scale S5 obtains the weight w of the high viscosity fluid flowing in. The density q of the high viscosity fluid is obtained through the electronic density meter S6 built into the sampling tube, and the volume of the high viscosity fluid flowing in per unit time is calculated. , then the actual flow data of high viscosity fluid ; The calibration scale factor is calculated by: ; Repeat the above sampling operation for n consecutive times, reset the electronic scale S5 continuously, weigh the items respectively, and obtain the proportional coefficient K continuously according to the above method. When the difference between the consecutive values is less than 1%, the self-calibration is completed. The sampling cylinder is internally provided with a liquid level switch. When the liquid level of the container reaches the upper limit, the solenoid valve coil of the compressed air is energized. The compressed air enters the sampling cylinder through the pressurized pipeline, and discharges the high-viscosity fluid through the 2# self-calibrating one-way electric valve and enters the internal circulation.

[0016] The present invention adopts the above technical solutions. Compared with the prior art, it has the following technical effects: Through self-calibration optimization, the influence of parameter changes such as fluid temperature, pressure, viscosity, and density on the measurement accuracy is eliminated. The problem of retention and blockage is solved through viscosity adjustment. The ultrasonic non-contact sensor is adopted, which is not affected by the fluid flow rate, realizing high-precision, high-stability, and high-speed liquid transportation and measurement; it is suitable for high-viscosity fluids, especially ultra-high viscosities above 100,000 cP, with a measurement accuracy of ±0.3%; the product change efficiency is improved, and the fluid change time < 15 minutes; it is suitable for the measurement of high-flow-rate and large-flow fluids, and the measurement accuracy will not decrease due to the increase in flow rate. Description of the Drawings

[0017] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0018] Figure 1 It is a schematic structural diagram of a high-viscosity fluid precision metering system in the present invention; Figure 2 It is a schematic structural diagram of the self-calibration module in the present invention; Figure 3 It is an electrical schematic diagram of the electric control module in the present invention; Figure 4 It is a flowchart of the implementation method of the high-viscosity fluid precision metering system in the present invention. Specific Embodiments

[0019] Embodiment, as Figure 1 and Figure 2 shown, a high-viscosity fluid precision metering system includes an electric control module, which is connected to a self-calibration module 9, a temperature compensation module 6, a power transmission module 7, and a sensing module 8. The temperature compensation module 6, the power transmission module 7, and the sensing module 8 are all installed on the pipeline where the high-viscosity fluid flows. The inlet of the pipeline is provided with a feed electric one-way valve KS1, and the outlet of the pipeline is provided with a discharge electric one-way valve.

[0020] The temperature compensation module 6 is used to heat the high-viscosity fluid to reduce its viscosity to within the threshold range, improving the fluidity of the high-viscosity fluid in the pipeline and solving the problem that the high-viscosity fluid has very poor self-fluidity and is not easy to be transported in the pipeline.

[0021] The power transmission module 7 includes a gear pump, which is connected to a variable frequency speed regulator for variable frequency speed regulation of the gear pump. The power transmission module 7 is connected to the temperature compensation module 6. The fluid whose viscosity is regulated by the temperature compensation module is driven by the variable frequency gear pump and transmitted in the pipeline at a certain flow rate. By adjusting the frequency of the variable frequency motor of the gear pump, the flow rate of the fluid in the pipeline can be changed. The greater the flow rate, the greater the flow.

[0022] The sensing module 8 includes a viscosity sensor S3, a temperature sensor S1, a pressure sensor S2, an ultrasonic velocity measuring sensor S4, and an electronic densitometer S6. The viscosity sensor S3 monitors the viscosity data in real time and feeds it back to the temperature compensation module. The temperature sensor S1 monitors the temperature data in real time. Through the adjustment of temperature and viscosity, a temperature / viscosity closed-loop regulation system is formed. The pressure sensor S2 is installed in the pipeline to detect the pressure value of the fluid in the pipeline. The ultrasonic velocity measuring sensor S4 is installed on the outer wall of the pipeline and can obtain the ultrasonic data electrical signal generated by the fluid flow. Through the processing of the electrical signal, the fluid velocity in the pipeline is obtained. The electronic densitometer S6 can obtain the density of the fluid in the pipeline.

[0023] The self-calibration module 9 includes a sampling cylinder 1. An electronic scale S5 is provided at the bottom of the sampling cylinder 1. The sampling cylinder 1 is connected with a sampling feed pipeline 3, a sampling discharge pipeline 4, and a pressurizing pipeline 5. The sampling feed pipeline 3 is connected to the feed point of the pipeline where the high-viscosity fluid flows. The sampling discharge pipeline 4 is connected to the discharge point of the pipeline where the high-viscosity fluid flows. A 2# self-calibration electric one-way valve is provided on the sampling feed pipeline 3, and a 1# self-calibration electric one-way valve is provided on the sampling discharge pipeline 4. The pressurizing pipeline 5 is used to input compressed air into the sampling cylinder 1. A compressed air solenoid valve is provided on the pressurizing pipeline 5. The actual flow rate of the fluid can be calculated by measuring the fluid weight, and the data of the ultrasonic velocity measuring sensor S4 can be calibrated to improve the measurement accuracy.

[0024] The electric control module collects the signals of each sensor and conducts data processing. Through an adaptive algorithm, dynamic compensation data is established, and a big data model of process parameters and scale factors is constructed.

[0025] As Figure 3As shown in the figure, the electric control module includes a PLC and a power supply. One end of the positive pole of the power supply is connected to one end of the stop button K1. The other end of the stop button K1 is connected to one end of the start button K2 and one end of the self-holding contact of the main relay KM1. The other end of the start button K2 and the other end of the self-holding contact of the main relay KM1 are connected to one end of the coil of the main relay KM1 and one end of the main contact of the main relay KM1. The other end of the coil of the main relay KM1 is connected to the negative pole of the power supply. The other end of the main contact of the main relay KM1 is connected to the PLC, the temperature compensation module, one end of the coil of the feeding electric check valve KS1, one end of the frequency converter SQ, one end of the temperature sensor S1, one end of the pressure sensor S2, one end of the viscosity sensor S3, one end of the ultrasonic speed measuring sensor S4, one end of the electronic scale S5, and one end of the electronic density meter S6. The other end of the coil of the feeding electric check valve KS1, the other end of the frequency converter SQ, the other end of the temperature sensor S1, the other end of the pressure sensor S2, the other end of the viscosity sensor S3, the other end of the ultrasonic speed measuring sensor S4, the other end of the electronic scale S5, and the other end of the electronic density meter S6 are connected to the negative pole of the power supply.

[0026] The signal output terminal OUT1 of the temperature sensor S1 is connected to the input terminal IN1 of the PLC. The signal output terminal OUT2 of the pressure sensor S2 is connected to the input terminal IN2 of the PLC. The signal output terminal OUT3 of the viscosity sensor S3 is connected to the input terminal IN3 of the PLC. The signal output terminal OUT4 of the ultrasonic speed measuring sensor S4 is connected to the input terminal IN4 of the PLC. The signal output terminal OUT5 of the electronic scale S5 is connected to the input terminal IN5 of the PLC. The signal output terminal OUT6 of the electronic density meter S6 is connected to the input terminal IN6 of the PLC.

[0027] The PLC is connected to one end of the coil of the 1# self-calibration electric check valve KS2, one end of the coil of the 2# self-calibration electric check valve KS3, one end of the coil of the compressed air solenoid valve KS4, and one end of the coil of the discharging electric check valve KS5. The other end of the coil of the 1# self-calibration electric check valve KS2, the other end of the coil of the 2# self-calibration electric check valve KS3, the other end of the coil of the compressed air solenoid valve KS4, and the other end of the coil of the discharging electric check valve KS5 are connected to the negative pole of the power supply.

[0028] As Figure 4 shown, a method for realizing a high-viscosity fluid precision metering system includes the following steps: Step 1. Execute the self-calibration internal loop: Press the start button, the coil of the main relay is energized and self-held, the main contact of the main relay closes, and the feeding electric check valve opens; The PLC controls the discharging electric check valve to close, the 1# self-calibration check valve opens, the 2# self-calibration check valve opens, and the high-viscosity fluid enters the pipeline through the feeding electric check valve; The high-viscosity fluid flows through the temperature compensation module, gear pump, ultrasonic velocity sensor S4, 1# self-calibrating one-way electric valve, self-calibration module, and 2# self-calibrating one-way electric valve. Then, the high-viscosity fluid enters the temperature compensation module again for internal circulation.

[0029] Specifically, it includes the following steps: Step 1.1: Temperature compensation to adjust the fluid viscosity; The self-fluidity of the high-viscosity fluid is very poor. The temperature compensation module heats the high-viscosity fluid to 50 - 80 °C to increase its fluidity and make its viscosity value between 15,000 - 30,000 centipoise. The temperature sensor S1 and viscosity sensor S3 obtain the temperature and viscosity values and send the data to the electronic control module.

[0030] Step 1.2: Variable frequency speed regulation to adjust the fluid flow rate; The variable frequency speed regulator of the power transmission module drives the gear pump to operate. The high-viscosity fluid is transported in the pipeline at a certain flow rate. To adapt to different transport volumes, the output frequency of the variable frequency speed regulator is increased or decreased to adjust the flow rate of the high-viscosity fluid in the pipeline. The ultrasonic velocity sensor S4 monitors the fluid velocity value in the pipeline and sends the data to the electronic control module.

[0031] Step 1.3: Measurement calibration; Theoretically, by obtaining the fluid velocity through the ultrasonic velocity sensor S4 on the outer wall of the pipeline and multiplying it by the cross-sectional area of the pipeline (the cross-sectional area of the pipeline is a constant), the fluid flow rate can be obtained. In actual situations, the temperature, pressure, viscosity, density, etc. of the fluid in the pipeline will all affect the electrical signal data detected by ultrasonic waves, reducing the accuracy of the detection data. Therefore, measurement calibration is required, and the steps are as follows: Step 1.3.1 Obtain the fluid parameter data in the pipeline; The temperature sensor S1 obtains the temperature data T, the pressure sensor S2 obtains the pressure data P, the viscosity sensor S3 obtains the viscosity data D, and the ultrasonic velocity sensor S4 obtains the flow velocity data V. The measurement calibration needs to be carried out in a stable parameter environment. Wait until the fluctuations of the above data are less than 1%, and then proceed to the next step.

[0032] Step 1.3.2 Calculate the fluid measurement reference data; According to the flow velocity data V obtained by the ultrasonic velocity sensor S4, multiplying it by the cross-sectional area S of the pipeline, the fluid measurement reference data FL_1 = V * S can be obtained. The reason why it is called reference data is that the sound wave signal of the ultrasonic velocity sensor S4 is easily affected by the temperature, pressure, viscosity, density, etc. of the fluid, and the test data has errors. That is to say, under the same fluid flow rate conditions, the temperature, pressure, viscosity, and density are different, and the flow rate data V obtained by the ultrasonic velocity sensor S4 is also different.

[0033] Step 1.3.3 Self-calibration, calculate the proportionality coefficient between the fluid measurement reference data and the true value; The self-calibration module includes a closed container sampling cylinder placed on the electronic scale S5. The electronic scale S5 has a zeroing function. High-viscosity fluid can flow in multiple times and be weighed multiple times to obtain weight data until the liquid level in the sampling cylinder reaches the upper limit, and the sampling cylinder is emptied, and then flowed in again and weighed, and the cycle continues; Within the unit sampling time △t, the high viscosity fluid flows into the sampling tube through the 1# self-calibration one-way electric valve. The electronic scale S5 obtains the weight w of the high viscosity fluid flowing in. The density q of the high viscosity fluid is obtained through the electronic density meter S6 built into the sampling tube, and the volume of the high viscosity fluid flowing in per unit time is calculated. , then the actual flow data of high viscosity fluid ; The calibration scale factor is calculated by: ; Repeat the above sampling operation for n consecutive times, reset the electronic scale S5 continuously, weigh respectively, and obtain the proportional coefficient K continuously according to the above method. When the difference between the consecutive values is less than 1%, the self-calibration is completed.

[0034] The sampling cylinder has a built-in liquid level switch. When the liquid level in the container reaches the upper limit, the coil of the compressed air solenoid valve is energized, and the compressed air enters the sampling cylinder through the pressurized pipe, discharging the high-viscosity fluid through the 2# self-calibration one-way electric valve and entering the internal circulation.

[0035] Step 2. System external circulation: PLC controls to close the 1# self-calibration one-way electric valve, close the 2# self-calibration one-way electric valve, open the discharge electric one-way valve, and the fluid is transferred from the internal circulation to the external circulation; The high-viscosity fluid feeds into the pipeline through the electric one-way valve, passes through the temperature compensation module, gear pump, ultrasonic speed sensor S4, and flows out of the discharge pipeline through the electric one-way valve; By monitoring the flow rate data obtained by the ultrasonic velocity sensor S4, the fluid measurement reference data FL_1 can be used to calibrate the proportional coefficient K to obtain the actual flow rate of the fluid. .

[0036] Step 3. Build a system-adaptive big data model: Furthermore, since the calibration proportional coefficient K is related to temperature T, pressure P, viscosity D, and density q, a data association model of each parameter proportional factor is established: K = T * k1 + P * k2 + D * k3 + q * k4; Where k1 is the temperature proportionality factor, k2 is the pressure proportionality factor, k3 is the viscosity proportionality factor, and k4 is the density proportionality factor.

[0037] Through big data analysis, self-learning is carried out to draw the relationship curves between each parameter and the proportionality factor (T-k1 curve, P-k2 curve, D-k3 curve, q-k4 curve). In this way, when changing the production (changing the variety of high-viscosity fluids) or changing the process parameters (temperature, pressure, viscosity, density), there is no need to perform self-calibration again. Through the relationship curves between each parameter and the proportionality factor, the corresponding proportionality factor values of k1, k2, k3, and k4 can be quickly obtained according to the data of each sensor. Through the formula K = T * k1 + P * k2 + D * k3 + q * k4, the calibrated proportionality coefficient K is obtained. By multiplying the calibrated proportionality coefficient K by the flow data of the ultrasonic velocity measurement sensor S4, the true and accurate measurement data can be obtained. Specific implementation method: For example, a set of high-viscosity fluid precision measurement systems mentioned in the present invention has established a parameter-proportionality factor curve model (T-k1 curve, P-k2 curve, D-k3 curve, q-k4 curve) through big data collection and analysis. Now it is necessary to transport a high-viscosity fluid through a DN25 pipeline. After measurement by each sensor, the temperature data is obtained as 75 degrees Celsius, the pressure data is 0.55 MPa, the viscosity data is 17700 cP, the density data is 2.75 kg / m³, and the fluid velocity in the pipeline is 0.15 m / s.

[0039] Through the T-k1 curve, the value of k1 is obtained as 0.00393 when the temperature is 75 degrees Celsius. Through the P-k2 curve, the value of k2 is obtained as 0.517 when the pressure is 0.55 MPa. Through the D-k3 curve, the value of k3 is obtained as 0.0000182 when the viscosity is 17700 cP. Through the q-k4 curve, the value of k4 is obtained as 0.0997 when the density is 2.75 kg / m³. Substitute each data into the formula: K = T * k1 + P * k2 + D * k3 + q * k4 = 75 * 0.00393 + 0.55 * 0.517 + 17700 * 0.0000182 + 2.75 * 0.0997 = 1.175415; It is known that the cross-sectional area of the DN25 pipeline is S = 0.000491 square meters, and the fluid measurement reference data: FL_1 = V * S = 0.15 * 0.000491 = 0.000007365 cubic meters per second; True flow rate cubic meters per second.

[0040] The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, and to enable others of ordinary skill in the art to understand the invention for the purpose of designing various embodiments with various modifications suited to particular uses.

Claims

1. A high-viscosity fluid precision metering system, characterized in that: It includes an electronic control module, which is connected with a self-calibration module, a temperature compensation module, a power transmission module and a sensing module. The temperature compensation module, the power transmission module and the sensing module are all installed on the pipeline where the high-viscosity fluid flows. An inlet feed electric check valve is provided at the inlet of the pipeline, and an outlet discharge electric check valve is provided at the outlet of the pipeline; The power transmission module includes a gear pump, which is connected with a variable frequency speed regulator. The power transmission module is connected with the temperature compensation module, and the fluid whose viscosity is adjusted by the temperature compensation module is driven by the gear pump with variable frequency speed regulation; The self-calibration module includes a sampling cylinder. An electronic scale S5 is provided at the bottom of the sampling cylinder. The sampling cylinder is connected with a sampling feed pipeline, a sampling discharge pipeline and a pressurization pipeline. The sampling feed pipeline is connected to the feed point of the pipeline where the high-viscosity fluid flows, and the sampling discharge pipeline is connected to the discharge point of the pipeline where the high-viscosity fluid flows. A 2# self-calibration electric check valve is provided on the sampling feed pipeline, and a 1# self-calibration electric check valve is provided on the sampling discharge pipeline. The pressurization pipeline is used to input compressed air into the sampling cylinder, and a compressed air solenoid valve is provided on the pressurization pipeline.

2. The high-viscosity fluid precision metering system according to claim 1, characterized in that: The electronic control module includes a PLC and a power supply. The positive pole of the power supply is connected to one end of a stop button K1. The other end of the stop button K1 is connected to one end of a start button K2 and one end of a self-holding contact of a main relay KM1. The other end of the start button K2 and the other end of the self-holding contact of the main relay KM1 are connected to one end of the coil of the main relay KM1 and one end of the main contact of the main relay KM1. The other end of the coil of the main relay KM1 is connected to the negative pole of the power supply.

3. The high-viscosity fluid precision metering system according to claim 2, wherein: The other end of the main contact of the main relay KM1 is connected to the PLC, the temperature compensation module, one end of the coil of the inlet feed electric check valve KS1, one end of the variable frequency speed regulator SQ, one end of the temperature sensor S1, one end of the pressure sensor S2, one end of the viscosity sensor S3, one end of the ultrasonic speed measurement sensor S4, one end of the electronic scale S5, and one end of the electronic density meter S6. The other ends of the coil of the inlet feed electric check valve KS1, the variable frequency speed regulator SQ, the temperature sensor S1, the pressure sensor S2, the viscosity sensor S3, the ultrasonic speed measurement sensor S4, the electronic scale S5, and the electronic density meter S6 are connected to the negative pole of the power supply.

4. The high-viscosity fluid precision metering system according to claim 3, wherein: The signal output terminal OUT1 of the temperature sensor S1 is connected to the input terminal IN1 of the PLC. The signal output terminal OUT2 of the pressure sensor S2 is connected to the input terminal IN2 of the PLC. The signal output terminal OUT3 of the viscosity sensor S3 is connected to the input terminal IN3 of the PLC. The signal output terminal OUT4 of the ultrasonic speed measurement sensor S4 is connected to the input terminal IN4 of the PLC. The signal output terminal OUT5 of the electronic scale S5 is connected to the input terminal IN5 of the PLC. The signal output terminal OUT6 of the electronic density meter S6 is connected to the input terminal IN6 of the PLC.

5. The high-viscosity fluid precision metering system according to claim 2, characterized in that: The PLC is connected to one end of the coil of the 1# self-calibrating motorized one-way valve KS2, one end of the coil of the 2# self-calibrating motorized one-way valve KS3, one end of the coil of the compressed air solenoid valve KS4, and one end of the coil of the discharging motorized one-way valve KS5. The other ends of the coils of the 1# self-calibrating motorized one-way valve KS2, the 2# self-calibrating motorized one-way valve KS3, the compressed air solenoid valve KS4, and the discharging motorized one-way valve KS5 are connected to the negative pole of the power supply.

6. A method for implementing a high-viscosity fluid precision metering system, characterized in that: The implementation method is applied to a high-viscosity fluid precision metering system as described in any one of claims 1-5, and includes the following steps: Step 1. Execute self-calibrating internal circulation: Press the start button, the main relay coil is energized and self-locked, the main contacts of the main relay are closed, and the feeding motorized one-way valve is opened; The PLC controls the discharging motorized one-way valve to close, the 1# self-calibrating one-way motorized valve to open, and the 2# self-calibrating one-way motorized valve to open. The high-viscosity fluid enters the pipeline through the feeding motorized one-way valve; The high-viscosity fluid flows through the temperature compensation module, the gear pump, the ultrasonic velocity measuring sensor S4, the 1# self-calibrating one-way motorized valve, the self-calibrating module, and the 2# self-calibrating one-way motorized valve. Then, the high-viscosity fluid enters the temperature compensation module again for internal circulation; Step 2. System external circulation: The PLC controls the 1# self-calibrating one-way motorized valve to close and the 2# self-calibrating one-way motorized valve to close, and opens the discharging motorized one-way valve. The fluid changes from internal circulation to external circulation; The high-viscosity fluid enters the pipeline through the feeding motorized one-way valve, passes through the temperature compensation module, the gear pump, the ultrasonic velocity measuring sensor S4, and flows out of the pipeline through the discharging motorized one-way valve; By monitoring the flow velocity data obtained by the ultrasonic velocity measurement sensor S4, the fluid metering reference data FL_1 can be obtained, and the true fluid flow rate can be obtained by calibrating the proportionality coefficient K. ; Step 3. Build a system adaptive big data model: Since the calibration proportionality coefficient K is related to the temperature T, pressure P, viscosity D, and density q, establish a data correlation model for the proportionality factors of each parameter: K = T*k1 + P*k2 + D*k3 + q*k4; Where k1 is the temperature proportionality factor, k2 is the pressure proportionality factor, k3 is the viscosity proportionality factor, and k4 is the density proportionality factor; Through big data analysis, self-learning is carried out, and the relationship curves between each parameter and the proportionality factor are drawn. In this way, when changing products or process parameters, there is no need to perform self-calibration again. Through the relationship curves between each parameter and the proportionality factor, the corresponding proportionality factor values of k1, k2, k3, and k4 can be quickly obtained according to the data of each sensor. Through the formula K = T*k1 + P*k2 + D*k3 + q*k4, the calibration proportionality coefficient K is obtained. By multiplying the calibration proportionality coefficient K by the flow data of the ultrasonic velocity measuring sensor S4, the true and accurate metering data can be obtained.

7. The implementation method of a high-viscosity fluid precision metering system as described in claim 6, characterized in that: The specific steps of Step 1 include the following steps: Step 1.1: Temperature compensation to adjust the fluid viscosity; The self-fluidity of the high-viscosity fluid is very poor. The high-viscosity fluid is heated to 50-80 °C through the temperature compensation module to increase its fluidity and make its viscosity value between 15,000 and 30,000 centipoise; The temperature sensor S1 and the viscosity sensor S3 obtain the temperature and viscosity values and send the data to the electronic control module; Step 1.2: Variable frequency speed regulation to adjust the fluid flow rate; The variable frequency speed regulator of the power transmission module drives the gear pump to operate, and the high-viscosity fluid is transmitted in the pipeline at a certain flow rate; to adapt to different conveying volumes, the output frequency of the variable frequency speed regulator is increased or decreased to adjust the flow rate of the high-viscosity fluid in the pipeline; The ultrasonic speed measurement sensor S4 monitors the fluid speed value in the pipeline and sends data to the electronic control module; Step 1.3: Measurement calibration; Theoretically, by obtaining the fluid speed through the ultrasonic speed measurement sensor S4 on the outer wall of the pipeline and multiplying it by the cross-sectional area of the pipeline, the fluid flow rate can be obtained. In actual situations, the temperature, pressure, viscosity, and density of the fluid in the pipeline will all affect the electrical signal data detected by ultrasonic waves, reducing the accuracy of the detection data. Therefore, measurement calibration is required.

8. The implementation method of a high-viscosity fluid precision metering system as claimed in claim 7, characterized in that: The measurement calibration includes the following steps: Step 1.3.1 Obtain the fluid parameter data in the pipeline; The temperature sensor S1 obtains the temperature data T, the pressure sensor S2 obtains the pressure data P, the viscosity sensor S3 obtains the viscosity data D, and the ultrasonic speed measurement sensor S4 obtains the flow rate data V. The measurement calibration needs to be carried out in a stable parameter environment. Wait until the fluctuations of the above data are less than 1%, and then proceed to the next step; Step 1.3.2 Calculate the fluid measurement reference data; According to the flow rate data V obtained by the ultrasonic speed measurement sensor S4, multiplying it by the cross-sectional area S of the pipeline, the fluid measurement reference data FL_1 = V * S can be obtained; Step 1.3.3 Self-calibration, calculate the proportionality coefficient between the fluid measurement reference data and the true value; The high-viscosity fluid can flow into the sampling cylinder in multiple times, and the weight data is obtained by weighing multiple times until the liquid level of the sampling cylinder reaches the upper limit. Then, start to empty the sampling cylinder, and then flow in and weigh again, repeating this cycle; Within the unit sampling time Δt, the high-viscosity fluid flows into the sampling cylinder through the 1# self-calibrating one-way electric valve. The electronic scale S5 obtains the weight w of the high-viscosity fluid flowing in, and the density q of the high-viscosity fluid is obtained through the electronic densitometer S6 built into the sampling cylinder, and the volume of the high-viscosity fluid flowing in per unit time is calculated. , then the true flow rate data of the high-viscosity fluid ; The calibration proportionality coefficient is obtained by calculation: ; Repeat the above steps, perform continuous n sampling operations, the electronic scale S5 is continuously cleared and weighed separately. According to the above method, continuously obtain the proportionality coefficient K. When the difference between the continuous values is less than 1%, the self-calibration is completed; The sampling cylinder is equipped with a liquid level switch. When the liquid level of the container reaches the upper limit, the solenoid valve coil of the compressed air is energized, and the compressed air enters the sampling cylinder through the pressurized pipeline, and discharges the high-viscosity fluid through the 2# self-calibration one-way electric valve and enters the internal circulation.

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