CN112697211A - Portable turbine flowmeter - Google Patents
Portable turbine flowmeter Download PDFInfo
- Publication number
- CN112697211A CN112697211A CN202011378504.9A CN202011378504A CN112697211A CN 112697211 A CN112697211 A CN 112697211A CN 202011378504 A CN202011378504 A CN 202011378504A CN 112697211 A CN112697211 A CN 112697211A
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- Prior art keywords
- liquid level
- turbine
- coil
- comparator
- level sensor
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- 239000007788 liquid Substances 0.000 claims abstract description 85
- 238000005476 soldering Methods 0.000 claims description 6
- 239000003822 epoxy resin Substances 0.000 claims description 4
- 229920000647 polyepoxide Polymers 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 3
- 230000006870 function Effects 0.000 abstract description 6
- 238000010586 diagram Methods 0.000 description 12
- 230000006698 induction Effects 0.000 description 5
- 238000005259 measurement Methods 0.000 description 5
- 238000005070 sampling Methods 0.000 description 5
- 230000008859 change Effects 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Images
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
- G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
- G01F1/28—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by drag-force, e.g. vane type or impact flowmeter
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
- G01F15/02—Compensating or correcting for variations in pressure, density or temperature
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Details Of Flowmeters (AREA)
Abstract
The invention relates to a portable turbine flowmeter, which comprises a turbine, a first coil, a second coil, a first comparator, a second comparator, a temperature sensor, a microprocessor, a display, a memory, a shell, an upper liquid level sensor, a lower liquid level sensor and a liquid level detector, wherein the first coil is arranged on the turbine; the turbine is positioned in the liquid in the shell, and a magnet is arranged in the turbine; the temperature sensor is placed in the mounting hole of the shell; a liquid level detector for detecting the liquid level in the shell is arranged in the shell; the first coil and the second coil are matched with a magnet arranged in the turbine; one end of the first comparator and one end of the second comparator are respectively connected to the first coil and the second coil, and the other ends of the first comparator and the second comparator are connected to the microprocessor; the temperature sensor, the display, the memory, the upper liquid level sensor and the lower liquid level sensor are all connected to the microprocessor. The invention can still measure with high precision under the state of semi-oil and semi-gas of the pipeline, the precision is +/-0.2 percent, and the invention has the function of temperature compensation according to the different expansion coefficients of various oil products.
Description
Technical Field
The invention relates to a flowmeter, in particular to a portable turbine flowmeter which can perform compensation calculation when the semi-oil and semi-gas state of a pipeline is near the end of oil discharge, achieves the purposes of completely discharging oil and accurately metering (the precision is +/-0.2%) and has a temperature compensation function.
Background
At present, when the oil is discharged to the last two or three hundred liters, the tank car oil discharge flow meter in the market generally adopts a weighing method for oil of the last two or three hundred liters at present to measure, and the efficiency is very low because the metering precision is inaccurate and the oil can not be completely discharged due to the semi-oil and semi-air state in a pipeline.
Disclosure of Invention
In view of the above problems, the main object of the present invention is to provide a portable turbine flowmeter capable of performing compensation calculation when the pipeline is in a semi-oil and semi-gas state when oil discharge is completed, so as to achieve the purpose of complete oil discharge and accurate metering (the accuracy is ± 0.2%), and having a temperature compensation function.
The invention solves the technical problems through the following technical scheme: a portable turbine flow meter, the portable turbine flow meter comprising:
the liquid level sensor comprises a turbine, a first coil, a second coil, a first comparator, a second comparator, a temperature sensor, a microprocessor, a display, a memory, a shell, an upper liquid level sensor, a lower liquid level sensor and a liquid level detector;
the turbine is positioned in the liquid in the shell, and a magnet is arranged in the turbine;
the temperature sensor is placed in the mounting hole of the shell; a liquid level detector for detecting the liquid level in the shell is arranged in the shell;
the first coil and the second coil are positioned above the shell and are matched with a magnet arranged in the turbine;
one end of the first comparator is connected to the first coil, and the other end of the first comparator is connected to the microprocessor;
one end of the second comparator is connected to the second coil, and the other end of the second comparator is connected to the microprocessor;
the temperature sensor, the display, the memory, the upper liquid level sensor and the lower liquid level sensor are all connected to the microprocessor.
In a specific embodiment of the invention: the temperature sensor is placed in the mounting hole of the shell and is pressed and fixed by a retainer ring through the hole, and the middle of the temperature sensor is sealed by an O-shaped ring.
In a specific embodiment of the invention: the first coil and the second coil are fixed on the circuit board through tin soldering.
In a specific embodiment of the invention: the upper liquid level sensor and the lower liquid level sensor are connected with the shell through threads, and the connecting hole is sealed by a plug and filled with epoxy resin for sealing.
In a specific embodiment of the invention: the first comparator, the second comparator, the microprocessor, the display and the memory are fixed on the circuit board through soldering.
In a specific embodiment of the invention: and the upper liquid level sensor, the lower liquid level sensor and the temperature sensor are all connected with the wiring terminal of the circuit board through signal wires.
The positive progress effects of the invention are as follows: the portable turbine flowmeter provided by the invention has the following advantages: the high-precision measurement can be still carried out under the state of semi-oil and semi-gas in the pipeline, the precision is +/-0.2 percent, and the temperature compensation function is realized according to different expansion coefficients of various oil products.
Drawings
Fig. 1 is a schematic view of the overall structure of the invention.
FIG. 2 is a schematic view of the turbine section of the present invention.
Fig. 3 is a schematic structural diagram of the shell in the invention.
Fig. 4 is a schematic structural diagram of a comparator in the invention.
Fig. 5-1 is a schematic view of the invention with the liquid level in the shell at full tube.
Fig. 5-2 is a schematic structural diagram of the invention when the liquid level in the shell is in a half-pipe.
5-3 are schematic structural diagrams of the liquid level in the shell when the pipe is empty in the invention.
Fig. 6 is a schematic structural view of the temperature sensor of the present invention being placed in the mounting hole of the housing.
FIG. 7 is a schematic structural view of the connection between the liquid level sensor and the housing according to the present invention.
The following are the names corresponding to the marks in the invention:
the device comprises a turbine 1, a first coil 2, a second coil 3, a first comparator 4, a second comparator 5, a temperature sensor 6, a microprocessor 7, a display 8, a memory 9, a shell 10, an upper liquid level sensor 11, a lower liquid level sensor 12, a liquid level detector 13, a hole check ring 14, an O-shaped ring 15, a plug 16, epoxy resin 17 and a magnet 18.
Detailed Description
The following provides a detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings.
Fig. 1 is a schematic diagram of the overall structure of the invention, fig. 2 is a schematic diagram of the structure of a turbine part in the invention, fig. 3 is a schematic diagram of the structure in a first oil container in the invention, and fig. 4 is a schematic diagram of the structure of a comparator in the invention, as shown in fig. 1-4: the invention provides a portable turbine flowmeter, comprising: the device comprises a turbine 1, a first coil 2, a second coil 3, a first comparator 4, a second comparator 5, a temperature sensor 6, a microprocessor 7, a display 8, a memory 9, a shell 10, an upper liquid level sensor 11, a lower liquid level sensor 12 and a liquid level detector 13; the turbine 1 is positioned in the liquid in the shell 10, and the magnet 18 is arranged in the turbine 1; the temperature sensor 6 is placed in the mounting hole of the shell 10; a liquid level detector 13 for detecting the liquid level in the housing 10 is installed in the housing 10; the first coil 2 and the second coil 3 are positioned above the shell 10, and the first coil 2 and the second coil 3 are matched with a magnet arranged in the turbine 2; one end of the first comparator 4 is connected to the first coil 2, and the other end is connected to the microprocessor 7; one end of the second comparator 5 is connected to the second coil 3, and the other end is connected to the microprocessor 7; the temperature sensor 6, the display 8, the memory 9, the upper liquid level sensor 11 and the lower liquid level sensor 12 are all connected to the microprocessor 7. The first coil 2 and the second coil 3 are fixed to the circuit board by soldering. The first comparator 4, the second comparator 5, the microprocessor 7, the display 8 and the memory 9 are fixed on the circuit board by soldering. The upper liquid level sensor 11, the lower liquid level sensor 12 and the temperature sensor 6 are connected with wiring terminals of a circuit board through signal wires.
Fig. 5-1 is a schematic view of the invention with the liquid level in the shell at full tube. Fig. 5-2 is a schematic structural diagram of the invention when the liquid level in the shell is in a half-pipe. 5-3 are schematic structural diagrams of the liquid level in the shell when the pipe is empty in the invention. As shown in the three figures above: sensing of the liquid level in the upper level sensor 11 and the lower level sensor 12 in three cases.
Fig. 6 is a schematic structural view of the temperature sensor of the present invention being placed in the mounting hole of the housing. As shown in fig. 6: the temperature sensor 6 is placed in the mounting hole of the shell 10, is pressed and fixed by a retainer ring 14 through the hole, and is sealed by an O-shaped ring 15 in the middle.
FIG. 7 is a schematic structural view of the connection between the liquid level sensor and the housing according to the present invention. As shown in fig. 7: the upper liquid level sensor 11 and the lower liquid level sensor 12 are connected with the shell through threads, and the connecting hole is sealed by a plug 16 and filled with epoxy resin 17 for sealing.
Fig. 1 is a schematic diagram of the overall structure of the portable turbine flowmeter, which is a simple schematic block diagram of the portable turbine flowmeter, and the portable turbine flowmeter is mainly used for unloading oil from an oil tank truck.
When the flow speed of oil in the pipeline exceeds the initial flow and passes through the turbine, the turbine is driven to rotate, the rotating speed of the turbine is in direct proportion to the instantaneous flow of the oil in the pipeline, so that the instantaneous flow in the pipeline can be obtained only by measuring the rotating speed of the turbine and multiplying the rotating speed by a coefficient, and the instantaneous flow in a period of time is accumulated to calculate the accumulated flow in a period of time.
The blade of the turbine is embedded with a plurality of permanent magnets, according to Faraday's law of electromagnetic induction, when the turbine rotates, the magnetic field generated by the permanent magnets can be alternatively close to or far away from two induction coils outside the sensor shell, the two induction coils can generate alternatively changed induction voltage, the faster the turbine rotating speed is, the higher the generated induction voltage is, and the faster the frequency of the alternatively changed induction voltage is. The frequency of the alternating induced voltage is directly proportional to the speed of the turbine.
Different from most turbine flowmeters which adopt a single coil to sample the turbine speed, the flowmeter adopts a double-coil sampling mode, and the mode can obviously improve the sampling precision of the turbine flowmeter.
As a turbine flowmeter for oil unloading of an oil tank truck, the turbine flowmeter is usually used for oil unloading through the gravity of oil products, so that the instantaneous flow is not very high, and the instantaneous flow is lower and lower in the oil unloading process, and the measurement accuracy of the meter at low flow speed is particularly important. The induced voltage signal generated by the coil at low flow speed is characterized in that the signal amplitude is very low, in order to accurately identify the frequency signal of the low-amplitude induced voltage at small flow, a high-precision low-noise comparator circuit is needed, a comparison threshold value adjusting circuit is also designed, when the turbine speed is low, the threshold value of the comparator can be adjusted to be low to improve the signal detection sensitivity of the comparator at low flow, and when the turbine speed is high, the threshold value of the comparator can be adjusted to be high to improve the signal quality of the comparator at high flow.
A situation of not full pipe in the turbine flowmeter generally occurs in the last few seconds or even minutes of oil discharge of the tank truck. The conventional turbine flowmeter has no liquid level detection function, and can only calculate in a full pipe mode, which causes a large error in the final accumulated flow.
When the upper liquid level sensor and the lower liquid level sensor detect liquid, instantaneous flow and accumulated calculation are carried out according to the coefficient when the pipe is full, when the upper liquid level sensor does not detect liquid and the lower liquid level sensor detects liquid, instantaneous flow and accumulated calculation are carried out according to the coefficient when the pipe is half, when the upper liquid level sensor and the lower liquid level sensor do not detect liquid and the turbine still rotates, the turbine is considered to be idle, the accumulated calculation is not carried out, and the instantaneous flow is set to zero.
When the temperature changes, the volume of the oil changes with the change of the temperature. The turbine flow meter is a volumetric flow meter, and the measurement results of the turbine flow meter are different at different temperatures for the same oil without temperature compensation.
In order to avoid trade dispute problems caused by temperature changes, a temperature sampling circuit of an oil product needs to be added in a flowmeter, instantaneous flow measured by a turbine flowmeter is converted into instantaneous flow at a standard temperature of 20 ℃, and then accumulated calculation is carried out. The formula of the instantaneous flow at the current temperature to the instantaneous flow at the standard temperature of 20 ℃ is as follows.
When the upper liquid level sensor and the lower liquid level sensor detect liquid, instantaneous flow and accumulated calculation are carried out according to the coefficient when the pipe is full, when the upper liquid level sensor does not detect liquid and the lower liquid level sensor detects liquid, instantaneous flow and accumulated calculation are carried out according to the coefficient when the pipe is half, when the upper liquid level sensor and the lower liquid level sensor do not detect liquid and the turbine still rotates, the turbine is considered to be idle, the accumulated calculation is not carried out, and the instantaneous flow is set to zero.
When the temperature changes, the volume of the oil changes with the change of the temperature. The turbine flow meter is a volumetric flow meter, and the measurement results of the turbine flow meter are different at different temperatures for the same oil without temperature compensation.
In order to avoid trade dispute problems caused by temperature changes, a temperature sampling circuit of an oil product needs to be added in a flowmeter, instantaneous flow measured by a turbine flowmeter is converted into instantaneous flow at a standard temperature of 20 ℃, and then accumulated calculation is carried out. The formula of the instantaneous flow at the current temperature to the instantaneous flow at the standard temperature of 20 ℃ is as follows.
When the upper liquid level sensor and the lower liquid level sensor detect liquid, instantaneous flow and accumulated calculation are carried out according to the coefficient when the pipe is full, when the upper liquid level sensor does not detect liquid and the lower liquid level sensor detects liquid, instantaneous flow and accumulated calculation are carried out according to the coefficient when the pipe is half, when the upper liquid level sensor and the lower liquid level sensor do not detect liquid and the turbine still rotates, the turbine is considered to be idle, the accumulated calculation is not carried out, and the instantaneous flow is set to zero.
When the temperature changes, the volume of the oil changes with the change of the temperature. The turbine flow meter is a volumetric flow meter, and the measurement results of the turbine flow meter are different at different temperatures for the same oil without temperature compensation.
In order to avoid trade dispute problems caused by temperature changes, a temperature sampling circuit of an oil product needs to be added in a flowmeter, instantaneous flow measured by a turbine flowmeter is converted into instantaneous flow at a standard temperature of 20 ℃, and then accumulated calculation is carried out.
The invention can still measure with high precision under the state of semi-oil and semi-gas of the pipeline, the precision is +/-0.2 percent, and the invention has the function of temperature compensation according to the different expansion coefficients of various oil products.
The foregoing shows and describes the general principles and features of the invention, together with the advantages thereof. It will be understood by those skilled in the art that the invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined by the appended claims and their equivalents.
Claims (6)
1. A portable turbine flow meter, characterized by: the portable turbine flow meter includes:
the liquid level sensor comprises a turbine, a first coil, a second coil, a first comparator, a second comparator, a temperature sensor, a microprocessor, a display, a memory, a shell, an upper liquid level sensor, a lower liquid level sensor and a liquid level detector;
the turbine is positioned in the liquid in the shell, and a magnet is arranged in the turbine;
the temperature sensor is placed in the mounting hole of the shell; a liquid level detector for detecting the liquid level in the shell is arranged in the shell;
the first coil and the second coil are positioned above the shell and are matched with a magnet arranged in the turbine;
one end of the first comparator is connected to the first coil, and the other end of the first comparator is connected to the microprocessor;
one end of the second comparator is connected to the second coil, and the other end of the second comparator is connected to the microprocessor;
the temperature sensor, the display, the memory, the upper liquid level sensor and the lower liquid level sensor are all connected to the microprocessor.
2. The portable turbine flowmeter of claim 1, wherein the temperature sensor is placed in a mounting hole of the housing and is pressed and fixed through the hole by a retainer ring, and an O-ring seal is arranged in the middle.
3. The portable turbine flowmeter of claim 1, wherein the first coil and the second coil are fixed to the circuit board by soldering.
4. The portable turbine flowmeter of claim 1, wherein the upper level sensor and the lower level sensor are connected to the housing by a screw thread, and the connecting hole is sealed by a plug, and the inside of the connecting hole is filled with epoxy resin for sealing.
5. The portable turbine flowmeter of claim 1, wherein the first comparator, the second comparator, the microprocessor, the display, and the memory are fixed to the circuit board by soldering.
6. The portable turbine flowmeter of claim 1, wherein the upper level sensor, the lower level sensor, and the temperature sensor are connected to the circuit board terminals via signal lines.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011378504.9A CN112697211A (en) | 2020-11-30 | 2020-11-30 | Portable turbine flowmeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011378504.9A CN112697211A (en) | 2020-11-30 | 2020-11-30 | Portable turbine flowmeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112697211A true CN112697211A (en) | 2021-04-23 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011378504.9A Pending CN112697211A (en) | 2020-11-30 | 2020-11-30 | Portable turbine flowmeter |
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| Country | Link |
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| CN (1) | CN112697211A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4962666A (en) * | 1989-01-11 | 1990-10-16 | Conoco Inc. | Mass flowmeter apparatus |
| CN101629837A (en) * | 2009-02-10 | 2010-01-20 | 中国人民解放军总后勤部油料研究所 | Liquid turbine flow meter and flow measuring method thereof |
| CN105606165A (en) * | 2016-02-24 | 2016-05-25 | 昆明理工大学 | Turbine real-time Bluetooth oil tank data acquisition device based on CPS embedded system |
| CN105606166A (en) * | 2016-03-29 | 2016-05-25 | 天津市青成自来水工程有限公司 | Pipeline flow meter |
| CN207263271U (en) * | 2017-09-29 | 2018-04-20 | 郑州永邦测控技术有限公司 | A kind of oil tank volume list automatic calibration system |
| CN208505384U (en) * | 2018-06-08 | 2019-02-15 | 广州研宏自动化仪表有限公司 | A kind of turbine flowmeter of cleaning easy to disassemble |
| CN109341785A (en) * | 2018-11-29 | 2019-02-15 | 安徽金大仪器有限公司 | A kind of turbine flowmeter with fluid density measurement function |
-
2020
- 2020-11-30 CN CN202011378504.9A patent/CN112697211A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4962666A (en) * | 1989-01-11 | 1990-10-16 | Conoco Inc. | Mass flowmeter apparatus |
| CN101629837A (en) * | 2009-02-10 | 2010-01-20 | 中国人民解放军总后勤部油料研究所 | Liquid turbine flow meter and flow measuring method thereof |
| CN105606165A (en) * | 2016-02-24 | 2016-05-25 | 昆明理工大学 | Turbine real-time Bluetooth oil tank data acquisition device based on CPS embedded system |
| CN105606166A (en) * | 2016-03-29 | 2016-05-25 | 天津市青成自来水工程有限公司 | Pipeline flow meter |
| CN207263271U (en) * | 2017-09-29 | 2018-04-20 | 郑州永邦测控技术有限公司 | A kind of oil tank volume list automatic calibration system |
| CN208505384U (en) * | 2018-06-08 | 2019-02-15 | 广州研宏自动化仪表有限公司 | A kind of turbine flowmeter of cleaning easy to disassemble |
| CN109341785A (en) * | 2018-11-29 | 2019-02-15 | 安徽金大仪器有限公司 | A kind of turbine flowmeter with fluid density measurement function |
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