CN111879381A - System and method for detecting accuracy of solid flow meter - Google Patents

Abstract

The invention provides a system and a method for detecting the accuracy of a solid flow meter.A discharging device is arranged to provide powder with stable discharging mass flow, the powder passes through a first conveying pipeline provided with the solid flow meter under the action of wind, and then the wind speed is adjusted by an air supply device so that the powder forms a stable pneumatic conveying state in the first conveying pipeline; and comparing the mass flow of the powder detected by the solid flow meter with the mass flow of the discharged powder provided by the discharging device to judge the accuracy of the solid flow meter. The discharging device of the invention adopts the magnetic coupling to improve the measurement precision of the powder discharging mass flow of the discharging device; meanwhile, the powder can be completely measured by the solid flow meter when being in a stable pneumatic conveying state, the detection accuracy of the solid flow meter is improved, the purpose of accurately measuring the accuracy of the solid flow meter is achieved, and the detection device is simpler.

Description

System and method for detecting accuracy of solid flow meter

Technical Field

The invention relates to the field of metering and detecting of solid flowmeters, in particular to a system and a method for detecting the accuracy of a solid flowmeter.

Background

At present, powder conveying is widely applied to industries such as energy, chemical industry, metallurgy and the like, for example, pulverized coal feeding of a power station boiler, heavy metal adsorbent spraying of coal-fired/solid waste garbage flue gas removal, coal injection of an iron-making blast furnace and the like. Therefore, the precise conveying of the powder is very important. In order to detect whether the mass flow of the powder meets the requirement, a solid flow meter is generally adopted to measure the powder in real time, so that the mass flow of the powder can be timely grasped and adjusted.

Common solid flow meters include microwave solid flow meters, electrostatic solid flow meters, and the like. According to the microwave solid flow meter, when a detected medium passes through a microwave detection field, a sensor transmits low-power microwaves and receives energy reflected by an object, the quantity and the flow speed of the moving medium are obtained through detection, and the solid mass flow is obtained through calculation. The principle of the electrostatic solid flow meter is that a certain degree of charges are accumulated in the powder in the pneumatic conveying process, when charged particles pass through a measuring pipe section, a sensor senses the charge number of the charged particles based on the electrostatic induction effect, a front-end circuit is connected with the sensor and amplifies signals, and then the solid mass flow can be calculated through calculation processing of a converter. How accurate the measurement result of the solid flow meter is particularly important for realizing accurate regulation and control of related industrial processes, so that the accuracy of the solid flow meter needs to be detected, but the existing detection method of the solid flow meter has great defects and seriously influences the reliability of the detection result. At present, the powder weigher's that adopts when weighing the measurement to the powder on the market feed rotating member and driving motor pass through mechanical type transmission, and the operation in-process, the last motor of weighing device has increased weighing device's bearing and the vibration is big, thereby can arouse weighing device to measure unstablely and make the metering result inaccurate, and the feed rate is undulant big, so lead to solid flow meter to detect the precision not high, be difficult to satisfy the detection requirement of the solid flow meter degree of accuracy.

The patent CN102140371A provides a method and system for metering a feeding amount and calibrating a solid flow meter on line. The system detects the solid flow meter according to the accumulated value of the weighing device, the accumulated value of the weighing device is a numerical value of the system running for a long time, so that the range of the selected weighing device is large, large errors are introduced into the detection process, the detection precision is not high, and meanwhile, the detection time is long.

Patent CN101545801A provides a calibration device and a use method for a solid mass flowmeter and a system containing the calibration device. This set of system includes that one set of dry process is sent out the material device, and in the testing process, the powder that uses the jar of weighing to send is collected and is weighed, because collect the in-process of weighing, has the powder to run off unavoidably to lead to weighing data unreliable, difficult requirement that reaches accurate detection solid flow meter, and this set of system detection device is also comparatively complicated.

Patent CN110864773A provides a method and system for online checking of accuracy of a solid flow meter. The principle is as follows: setting a comparison pipeline and a pipeline to be detected under the same operating conditions (wind speed, wind pressure, pipe diameter and the like); the mass flow of the powder on the pipeline to be compared is weighed by an accurate electronic scale, and the mass flow of the powder on the pipeline to be detected is measured by a flowmeter to be detected; setting the same powder flow conditions for the comparison pipeline and the pipeline to be detected according to respective powder weighing methods, wherein the pressure drop signals at the same interval on the comparison pipeline and the pipeline to be detected have the same characteristics if the powder flowmeter on the pipeline to be detected is accurate; on the contrary, the powder flowmeter on the pipeline to be detected is inaccurate, and the pressure drop signal characteristics of the same interval on the comparison pipeline and the pipeline to be detected are different under the same setting condition. The method can quickly judge the preliminary accuracy of the solid flow meter, but the accuracy and the error range are difficult to obtain.

In summary, the existing solid-state flow meter has the defects of low detection precision, complex detection device and the like. Therefore, a system and a method for detecting the accuracy of a solid flow meter, which have high detection accuracy and simple and effective detection devices, are still lacking.

Disclosure of Invention

The invention aims to provide a system and a method for detecting the accuracy of a solid flow meter, which are used for solving the problem that the conventional detection method of the solid flow meter cannot accurately detect the solid flow meter and solving the problem that the conventional detection device is complex.

In order to solve the problems, the method comprises the steps of firstly arranging a discharging device to provide powder with stable mass flow, enabling the powder to pass through a first conveying pipeline provided with a solid flow meter under the action of wind and then flow into a powder recovery device, and secondly adjusting the wind speed through an air supply device until the powder is not deposited in the first conveying pipeline, so that a stable pneumatic conveying state is formed; and comparing the mass flow of the powder detected by the solid flow meter with the discharging mass flow of the powder detected by the first data processor to judge the accuracy of the solid flow meter.

The invention provides a system and a method for detecting the accuracy of a solid flow meter, which have high detection precision and simple detection device, and the method comprises the following steps:

the invention designs a solid flowmeter accuracy detection system, which comprises a first material conveying pipeline, a solid flowmeter, a discharging device, an air supply device, a powder recovery device, a data collector and a data processor, wherein the first material conveying pipeline is connected with the solid flowmeter; a solid flow meter to be detected is arranged on the first material conveying pipeline;

along the powder material conveying direction, a feed inlet of the first material conveying pipeline is connected with a discharge outlet of a Venturi feeder, a feed inlet of the Venturi feeder is connected with a feed hopper through a second material conveying pipeline, and a discharging device is arranged on the feed hopper; the discharging device comprises a spiral discharger, a weighing hopper, a storage bin and a motor; the spiral discharger is arranged on the weighing device, the weighing hopper is connected with the spiral discharger, the storage bin is connected with the weighing hopper through a flexible connecting device, a quick feeding valve is arranged on the flexible connecting device, the motor is connected with the spiral discharger through a magnetic coupling, and the motor is connected with a motor controller. A magnetic coupling is adopted between a rotating shaft of the motor and a rotating shaft of the spiral discharger to realize non-contact transmission, so that the defect that the measurement of a weighing device is unstable due to the vibration of the motor can be overcome; the load bearing of the weighing device can be reduced, so that the weighing device with a small range can be adopted, the measurement precision is higher, and the accuracy of the powder discharging mass flow obtained by the first data processor is improved.

The air inlet of the venturi feeder is connected with the air supply device, the air supply device comprises a fan and an air pressure stabilizing tank which are sequentially connected through an air pipe, the outlet of the fan is connected with the inlet of the air pressure stabilizing tank, a fan valve is arranged between the outlet of the air pressure stabilizing tank and the air inlet of the venturi feeder, and the air pressure stabilizing tank is connected with an automatic exhaust valve through an air pipe; when the air blown by the fan passes through the narrow part of the Venturi pipe, the air pressure at the narrow part is reduced, and the adsorption effect is generated. Based on the principle, the venturi feeder is matched with the fan and the gas surge tank, so that the powder can form a pneumatic conveying state when certain air quantity is reached, and the detection accuracy of the solid flow meter is improved through the first conveying pipeline.

The data processor comprises a first data processor and a second data processor, the first data processor is connected with the weighing device, the powder mass measured by the weighing device in real time can be converted into the powder mass flow through the first data processor, the data collector is respectively connected with the first data processor and the solid flow meter to be detected, and the second data processor is connected with the data collector. The mass flow of the powder in the first material conveying pipeline detected by the solid flow meter and the powder discharging mass flow obtained by conversion of the first data processor are collected through the data collector and are processed through the second data processor together, so that the accuracy of the solid flow meter can be visually embodied.

The discharge port of the first material conveying pipeline is connected with the powder recovery device, so that the powder passing through the solid flow meter can be completely recovered and reused.

Therefore, the detection system designed by the invention has the advantages that on one hand, the magnetic coupling is adopted between the rotating shaft of the motor and the rotating shaft of the spiral discharger to realize non-contact transmission, so that the defect that the measurement of the weighing device is unstable due to the vibration of the motor is overcome, the bearing of the weighing device is lightened, the weighing device with a small range can be adopted, the detection accuracy of the mass flow rate of the discharged powder is improved, on the other hand, the powder forms a stable pneumatic conveying state in the first conveying pipeline by adjusting the air quantity, the detection accuracy of the solid flow meter is improved, the detection accuracy of the solid flow meter in the detection system is improved due to the synergistic effect of the two, and meanwhile, the accuracy of the solid flow meter can be directly obtained on.

Furthermore, the weighing hopper is provided with a material level meter, and the material level meter is respectively connected with the quick feeding valve, the alarm device and the motor controller.

Through set up a charge level indicator on the hopper of weighing, the powder height of hopper top position of weighing is kept away from in charge level indicator real-time supervision, when reaching the material level lower limit, the charge level indicator is simultaneously to quick feed valve, alarm device and motor controller signals, open quick feed valve and carry out the feed supplement, alarm device sends the warning jingle bell, powder can cause certain impact when falling into the hopper of weighing by gravity during owing to the feed supplement, the powder that can influence weighing device's accuracy and first data processor obtain arranges material mass flow, it is inaccurate to lead to the detection to the solid flow meter degree of accuracy, therefore the motor is closed in step, stop the detection to the solid flow meter degree of accuracy.

When the material level height in the weighing hopper reaches the upper limit of the material level, the material level meter sends signals to the quick feeding valve, the alarm device and the motor controller at the same time, the quick feeding valve is closed to stop feeding, the alarm device sends out a warning bell, the motor is synchronously started, and the detection on the accuracy of the solid flow meter is started.

Furthermore, the distance between the solid flowmeter to be detected and the Venturi feeder and the powder recovery device is 5-8 times of the diameter of the first material conveying pipeline. When the distance between the solid flow meter and the Venturi feeder is 5-8 times of the diameter of the first material conveying pipeline, the powder is uniformly distributed in the pipeline, and the mass flow can be calculated by combining the number and the state of the powder particles. When the distance between the solid flow meter and the powder recovery device is 5-8 times of the diameter of the first material conveying pipeline, the influence of disturbance on the solid flow meter caused by the cyclone of the rear powder recovery device on powder is avoided easily.

Furthermore, the invention designs that the feed opening of the spiral discharger extends downwards into the feed hopper, and the feed opening of the spiral discharger is in non-contact connection with the feed hopper so as to avoid influencing the weighing of the weighing device. The powder falling into the feed hopper flows under the adsorption action and the gravity action of the Venturi feeder.

Furthermore, the air pipe connecting the fan valve and the venturi feeder is provided with a gas flowmeter. The air flow meter can be used for measuring the air quantity in a pipeline in real time, and is favorable for quickly adjusting the fan valve to a proper opening degree.

Furthermore, the invention designs that a transparent window is arranged between the solid flow meter on the first material conveying pipeline and the powder recovery device. Whether powder in the first conveying pipeline has deposition phenomenon can be observed through setting up transparent window, and the amount of wind under the further assurance fan valve opening degree can make the powder satisfy the requirement that forms the air conveying state.

Furthermore, the powder recovery device comprises a cyclone dust collector, an electrostatic dust collector and a recovery hopper, wherein an inlet of the cyclone dust collector is connected with a discharge port of a first material conveying pipeline, a discharge port of the cyclone dust collector is connected with a first inlet of a discharge pipeline, an air outlet of the cyclone dust collector is connected with an inlet of the electrostatic dust collector, a discharge port of the electrostatic dust collector is connected with a second inlet of the discharge pipeline, and an outlet of the discharge pipeline is connected with the recovery hopper. The method is mainly used for completely recycling the powder.

The invention designs a method for detecting the accuracy of a solid flow meter, which utilizes the system for detecting the accuracy of the solid flow meter to set a discharging device to provide stable and accurately measurable powder discharging mass flow, wherein the powder discharging mass flow is set according to the range of the solid flow meter to be detected, so that powder flows through a first conveying pipeline provided with the solid flow meter under the action of wind provided by an air supply device, a powder recovery device recovers the powder flowing through the first conveying pipeline, and the air quantity of the air supply device is adjusted until the powder has no deposition phenomenon in the first conveying pipeline and is in a stable pneumatic conveying state; at this time, the powder can be determined to be in a flowing state in the first material conveying pipeline, and can be measured by the solid flow meter.

When the powder is in a stable pneumatic conveying state in the first conveying pipeline, the accuracy of the solid flowmeter to be detected is the percentage of the mass flow of the powder in the first conveying pipeline detected by the solid flowmeter at the moment and the powder discharging mass flow of the powder supplied by the discharging device measured by the first data processor. The powder can be completely measured by the solid flow meter when being in a stable pneumatic conveying state, so that the detection accuracy of the solid flow at the moment is the most accurate, and the powder discharge mass flow of the discharge device is compared and measured to obtain the accuracy of the accurate solid flow meter.

Furthermore, the height of the powder in the weighing hopper is detected through the material level meter, when the lower limit of the material level is reached, the material level meter simultaneously sends signals to the quick feeding valve, the alarm device and the motor controller, the quick feeding valve opens the supplementary material, the alarm device gives an alarm, and the motor controller controls the motor to close; when the material level height in the weighing hopper reaches the upper limit of the material level, the material level meter sends signals to the quick feed valve, the alarm device and the motor controller simultaneously, the quick feed valve is closed to stop feeding, the alarm device gives an alarm, and the motor controller controls the motor to start.

Furthermore, the mass flow of the powder discharging material designed by the invention can be adjusted according to the measuring range of the solid flowmeter, and meanwhile, the mass flow of the powder discharging material is kept stable and always accords with the set value after being changed. This application arranges material mass flow through motor controller adjustment powder many times, can detect solid flow meter's the degree of accuracy many times, and the accuracy that the average value, further improvement detected. In addition, the method is also suitable for detecting solid flow meters with different measuring ranges.

Furthermore, after the mass flow rate of the powder discharging is adjusted by the motor controller, the air quantity needs to be adjusted again until the powder is not deposited in the first material conveying pipeline and is in a new stable pneumatic conveying state, and then the accuracy of the solid flow meter is detected. Because the mass flow of the discharged powder is changed, the previous air volume cannot ensure that the powder is still in a stable pneumatic conveying state in the first conveying pipeline, and the air speed needs to be readjusted according to the newly adjusted mass flow of the discharged powder until the powder is not deposited in the first conveying pipeline, so that the powder in the first conveying pipeline can be ensured to be in the stable pneumatic conveying state.

Has the advantages that:

according to the technical scheme, the invention provides the accuracy detection system and method for the solid flowmeter, and the following beneficial effects can be achieved:

1. according to the invention, the discharging device which has constant powder discharging mass flow and can be accurately measured is arranged, the powder in the material conveying pipeline is ensured to be completely in a stable pneumatic conveying state, the mass flow of the powder in the first material conveying pipeline detected by the solid flow meter is compared and analyzed with the measured powder mass flow of the discharging device, and the detection precision of the accuracy of the solid flow meter is improved.

2. The invention adopts a Venturi feeder and a fan and a gas pressure stabilizing tank which are matched to exert the action on the powder flow together, and can ensure that the powder is completely in a stable pneumatic conveying state when enough air volume is ensured, thereby improving the detection accuracy of the solid flow meter.

3. The invention adopts the magnetic coupling to realize the non-contact transmission of the motor and the weighing device, and overcomes the defect of unstable measurement of the weighing device caused by the vibration of the motor; the load bearing of the weighing device can be reduced, so that the weighing device with a small range can be adopted, and the measurement precision of the powder discharging mass flow of the discharging device is further improved.

It should be understood that all combinations of the foregoing concepts and additional concepts described in greater detail below can be considered as part of the inventive subject matter of this disclosure unless such concepts are mutually inconsistent.

The foregoing and other aspects, embodiments and features of the present teachings can be more fully understood from the following description taken in conjunction with the accompanying drawings. Additional aspects of the present invention, such as features and/or advantages of exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of specific embodiments in accordance with the teachings of the present invention.

Drawings

The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic diagram of the system of the present invention.

Fig. 2 is a schematic view of the magnetic coupling of the present invention.

The meanings of the reference symbols in the figures are as follows: 1. a storage bin; 2. a fast feed valve; 3. a level gauge; 4. an alarm device; 5. a flexible connection device; 6. weighing a hopper; 7. a motor controller; 8. a spiral discharger; 9. a magnetic coupling; 10. an electric motor; 11. a feeding port; 12. a feed hopper; 13. a weighing device; 14. a gas flow meter; 15. a second delivery pipeline; 16. a first delivery conduit; 17. a solids flow meter; 18. a transparent window; 19. a cyclone dust collector; 20. an automatic exhaust valve; 21. a fan valve; 22. a venturi feeder; 23. an electrostatic precipitator; 24. a fan; 25. a gas surge tank; 26. a second data processor; 27. a data acquisition unit; 28. a first data processor; 29. a discharge conduit; 30. a recovery hopper; 31. a discharge device; 32. an air supply device; 33. a powder recovery device; 34. a drive shaft; 35. a driven shaft.

Detailed Description

In order to better understand the technical content of the present invention, specific embodiments are described below with reference to the accompanying drawings.

In this disclosure, aspects of the present invention are described with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. Embodiments of the present disclosure are not necessarily defined to include all aspects of the invention. It should be appreciated that the various concepts and embodiments described above, as well as those described in greater detail below, may be implemented in any of numerous ways, as the disclosed concepts and embodiments are not limited to any one implementation. In addition, some aspects of the present disclosure may be used alone, or in any suitable combination with other aspects of the present disclosure.

In order to solve the problem that the existing detection method of the solid flow meter 17 cannot accurately detect the solid flow meter and solve the problem that the existing detection device is complex, the method firstly arranges a discharging device 31 to provide stable powder for discharging mass flow, the powder passes through a first material conveying pipeline 16 provided with the solid flow meter 17 under the action of wind and then is recycled through a powder recycling device 33, and secondly, the wind speed is adjusted through a wind supply device 32 to enable the powder to form a stable pneumatic conveying state in the first material conveying pipeline 16; the powder mass flow detected by the solid flow meter 17 at this time is compared with the powder discharging mass flow provided by the discharging device 31 to judge the accuracy of the solid flow meter 17. The discharge device 31 of the invention creatively applies the magnetic coupling 9 to improve the measurement precision of the powder discharge mass flow of the discharge device 31; meanwhile, the powder can be measured by the solid flowmeter 17 when being in a stable pneumatic transmission state, so that the detection accuracy of the solid flowmeter 17 is the most accurate, the purpose of accurately measuring the accuracy of the solid flowmeter 17 is achieved, and meanwhile, the detection device in the application is simpler than the prior art.

In specific implementation, as shown in fig. 1, the invention designs an accuracy detection system for a solid flow meter 17, which comprises a first material conveying pipeline 16, the solid flow meter 17, a discharging device 31, an air supply device 32, a powder recovery device 33, a data acquisition device 27 and a data processor; a solid flow meter 17 to be detected is arranged on the first material conveying pipeline 16;

along the powder material conveying direction, the feed inlet of the first material conveying pipeline 16 is connected with the discharge outlet of a Venturi feeder 22, the feed inlet of the Venturi feeder 22 is connected with a feed hopper 12 through a second material conveying pipeline 15, and a discharging device 31 is arranged on the feed hopper 12; the discharging device 31 comprises a spiral discharger 8, a weighing hopper 6, a storage bin 1 and a motor 10; the spiral discharger 8 is arranged on the weighing device 13, the weighing hopper 6 is connected with the spiral discharger 8, the storage bin 1 is connected with the weighing hopper 6 through the soft connecting device 5, the weight of the storage bin 1 cannot be detected by the weighing device 13 due to the design of the soft connecting device 5, and the accuracy of detecting the mass flow of the powder fed by the discharging device 31 is improved; the quick feeding valve 2 is arranged on the soft connecting device 5, the motor 10 is connected with the spiral discharger 8 through the magnetic coupling 9, and the motor 10 is connected with the motor controller 7. The magnetic coupling 9 is adopted between the rotating shaft of the motor 10 and the rotating shaft of the spiral discharger 8 to realize non-contact transmission, as shown in fig. 2, a driving shaft 34 and a driven shaft 35 of the magnetic coupling 9 are arranged in a non-contact mode, the power of the motor 10 is transmitted to the driven shaft 35 from the driving shaft 34 by the magnetic coupling principle to drive the spiral discharger 8 to move, and the design overcomes the defect that the measurement of the weighing device 13 is unstable due to the vibration of the motor 10; the load bearing of the weighing device 13 can be reduced, so that the weighing device 13 with a small range can be adopted, the measurement precision is higher, and the accuracy of the powder discharging mass flow obtained by the first data processor 28 is improved.

The air inlet of the venturi feeder 22 is connected with the air supply device 32, the air supply device 32 comprises a fan 24 and a gas surge tank 25 which are sequentially connected through an air pipe, the outlet of the fan 24 is connected with the inlet of the gas surge tank 25, a fan valve 21 is arranged between the outlet of the gas surge tank 25 and the air inlet of the venturi feeder 22, and the gas surge tank 25 is connected with an automatic exhaust valve 20 through an air pipe; when the gas blown in by the blower 24 passes through the narrow part of the venturi tube, the pressure of the gas therein is reduced, thereby generating adsorption. Based on the principle, when the venturi feeder 22 is matched with the fan 24 and the gas surge tank 25 to reach a certain air quantity, the powder can form a pneumatic conveying state to pass through the first conveying pipeline 16, and the detection accuracy of the solid flow meter 17 is improved. The gas surge tank 25 serves as a safety device to control the pressure inside the system through the adjustment of the automatic exhaust valve 20; at the same time, by controlling the fan valve 21, the adjustability of the detection system can be increased.

The data processor comprises a first data processor 28 and a second data processor 26, the first data processor 28 is connected with the weighing device 13, the data collector 27 is respectively connected with the first data processor 28 and the solid flowmeter 17 to be detected, and the second data processor 26 is connected with the data collector 27. The powder mass measured by the weighing device 13 in real time can be converted into the powder mass flow through the first data processor 28; the mass flow of the powder in the first material conveying pipeline 16 detected by the solid flow meter 17 and the powder discharging mass flow obtained by conversion by the first data processor 28 are collected by the data collector 27 and are processed by the second data processor 26 together, so that the accuracy of the solid flow meter 17 can be visually embodied.

The discharge port of the first material conveying pipeline 16 is connected with a powder recovery device 33, so that the powder passing through the solid flow meter 17 can be completely recovered and reused.

Therefore, the detection system designed by the invention realizes non-contact transmission by adopting the magnetic coupling 9 between the rotating shaft of the motor 10 and the rotating shaft of the spiral discharger 8 on one hand, thereby overcoming the defect that the measurement of the weighing device 13 is unstable due to the vibration of the motor 10, reducing the load of the weighing device 13, thereby, the weighing device 13 with small measuring range can be adopted to improve the detection accuracy of the mass flow of the powder discharging material and the detection accuracy of the mass flow of the powder discharging material, on the other hand, the powder forms a stable pneumatic conveying state in the first conveying pipeline 16 by adjusting the air quantity, the detection accuracy of the solid flowmeter 17 is improved, the detection accuracy of the solid flowmeter 17 in the detection system is improved by the synergy of the two, meanwhile, the accuracy of the solid flow meter 17 can be directly obtained on line by connecting the data acquisition unit 27 and the data processor.

In specific implementation, the weighing hopper 6 is provided with the material level indicator 3, and the material level indicator 3 is respectively connected with the quick feeding valve 2, the alarm device 4 and the motor controller 7.

Through set up a charge level indicator 3 on weighing hopper 6, the powder height of 6 top positions of weighing hopper is kept away from to charge level indicator 3 real-time supervision, when reaching the material level lower limit, charge level indicator 3 is simultaneously to quick feed valve 2, alarm device 4 and motor controller 7 signals, open quick feed valve 2 and carry out the feed supplement, alarm device 4 sends the warning jingle bell, remind operating personnel to be about to stop the detection work, can cause certain impact when the powder falls into weighing hopper 6 by gravity during owing to the feed supplement, the powder row's material mass flow that accuracy and the first data processor 28 that can influence weighing device 13 obtained, lead to inaccurate to the detection of the solid flowmeter 17 degree of accuracy, consequently, synchronous motor 10 of closing, stop the detection to the solid flowmeter 17 degree of accuracy.

When the material level height in the weighing hopper 6 reaches the upper limit of the material level, the material level meter 3 simultaneously sends signals to the quick feed valve 2, the alarm device 4 and the motor controller 7, the quick feed valve 2 is closed to stop feeding, the alarm device 4 sends out a warning ring bell to remind an operator of about to start detection work, and the motor 10 is synchronously started to start detection of the accuracy of the solid flow meter 17.

In specific implementation, the distance between the solid flowmeter 17 to be detected and the Venturi feeder 22 and the powder recovery device 33 is 5-8 times of the diameter of the first material conveying pipeline 16. When the distance between the solid flow meter 17 and the Venturi feeder 22 is 5-8 times of the diameter of the first material conveying pipeline 16, the powder is uniformly distributed in the pipeline, and the mass flow can be calculated by combining the number and the state of the powder particles. When the distance between the solid flow meter 17 and the powder recovery device 33 is 5-8 times of the diameter of the first material conveying pipeline 16, the influence of the disturbance of the cyclone of the powder recovery device 33 on the solid flow meter 17 can be avoided.

In specific implementation, the discharge opening 11 of the spiral discharger 8 extends downwards into the feed hopper 12, and the discharge opening 11 of the spiral discharger 8 is in non-contact connection with the feed hopper 12, so that the weighing of the weighing device 13 is prevented from being influenced. The powder falling into the feed hopper 12 flows under the suction and gravity of the venturi feeder 22.

In specific implementation, the air pipe connecting the fan valve 21 and the venturi feeder 22 is provided with the gas flowmeter 14. The gas flowmeter 14 can be used for measuring the air quantity in the pipeline in real time, and is favorable for quickly adjusting the fan valve 21 to a proper opening degree.

In specific implementation, the invention is designed to arrange a transparent window 18 between the solid flow meter 17 on the first material conveying pipeline 16 and the powder recovery device 33. The transparent window 18 is arranged to observe whether the powder in the first material conveying pipeline 16 is deposited or not, so as to determine whether the air volume at the opening degree of the fan valve 21 meets the requirement of forming a pneumatic conveying state of the powder or not.

In specific implementation, the powder recovery device 33 provided by the invention comprises a cyclone 19, an electrostatic dust collector 23 and a recovery hopper 30, wherein an inlet of the cyclone 19 is connected with a discharge port of the first material conveying pipeline 16, a discharge port of the cyclone 19 is connected with a first inlet of the discharge pipeline 29, an air outlet of the cyclone 19 is connected with an inlet of the electrostatic dust collector 23, a discharge port of the electrostatic dust collector 23 is connected with a second inlet of the discharge pipeline 29, and an outlet of the discharge pipeline 29 is connected with the recovery hopper 30. The method is mainly used for completely recycling the powder.

In specific implementation, the invention designs a method for detecting the accuracy of a solid flow meter 17, and by using the system for detecting the accuracy of the solid flow meter 17, a discharging device 31 is set to provide a stable and accurately measurable powder discharging mass flow, the powder discharging mass flow is set according to the range of the solid flow meter 17 to be detected, so that powder flows through a first conveying pipeline 16 provided with the solid flow meter 17 under the action of air provided by an air supply device 32, a powder recovery device 33 recovers the powder flowing through the first conveying pipeline 16, and the air flow is adjusted until the powder has no deposition phenomenon in the first conveying pipeline 16 and is in a stable pneumatic conveying state; at this time, it is assumed that the powder is entirely in a flowing state in the first feed passage 16 and is entirely measured by the solid flow meter 17.

When the powder is in a stable pneumatic conveying state in the first conveying pipeline 16, the accuracy of the solid flow meter 17 to be detected is the percentage of the mass flow rate of the powder in the first conveying pipeline 16 detected by the solid flow meter 17 at this time to the powder discharging mass flow rate of the powder supplied by the discharging device 31 measured by the first data processor 28. Since all the powder can be measured by the solid flow meter 17 when the powder is in a stable pneumatic conveying state, the detection accuracy of the solid flow at this time is also the most accurate, and the accuracy of the solid flow meter 17 can be obtained by comparing and measuring the powder discharge mass flow with the powder discharge mass flow of the discharge device 31.

In specific implementation, the height of powder in a weighing hopper 6 is detected by a material level meter 3, when the lower limit of the material level is reached, the material level meter 3 simultaneously sends signals to a quick feed valve 2, an alarm device 4 and a motor controller 7, the quick feed valve 2 starts feeding, the alarm device 4 gives an alarm, and the motor controller 7 controls a motor 10 to be closed; when the material level height in the weighing hopper 6 reaches the upper limit of the material level, the material level meter 3 simultaneously sends signals to the quick feed valve 2, the alarm device 4 and the motor controller 7, the quick feed valve 2 is closed to stop feeding, the alarm device 4 gives an alarm, and the motor controller 7 controls the motor 10 to start.

In specific implementation, the mass flow rate of the powder discharging material designed by the invention can be adjusted according to the measuring range of the solid flowmeter 17, and meanwhile, the mass flow rate is kept stable and always accords with the set value after being changed. This application arranges material mass flow through motor controller 7 adjustment powder many times, can detect solid flowmeter 17's the degree of accuracy many times, and the degree of accuracy that the further improvement detected is averaged. The method is also suitable for detecting the solid flow meter 17 with different measuring ranges.

In specific implementation, after the mass flow rate of the powder discharging is adjusted by the motor controller 7, the air quantity needs to be adjusted again until the powder is not deposited in the first material conveying pipeline 16 and is in a new stable pneumatic conveying state, and then the accuracy of the solid flow meter 17 is detected. Since the mass flow rate of powder discharged material is changed, the previous air volume cannot ensure that the powder is still in a stable pneumatic conveying state in the first conveying pipeline 16, and the air speed needs to be readjusted according to the newly adjusted mass flow rate of powder discharged material until the powder is not deposited in the first conveying pipeline 16, so as to ensure that the powder in the first conveying pipeline 16 is in a stable pneumatic conveying state.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention should be determined by the appended claims.

Claims (10)

1. A solid flow meter accuracy detection system characterized by: the device comprises a first material conveying pipeline, a solid flow meter, a discharging device, an air supply device, a powder recovery device, a data acquisition unit and a data processor; a solid flow meter to be detected is arranged on the first material conveying pipeline;

along the powder material conveying direction, a feed inlet of the first material conveying pipeline is connected with a discharge outlet of a Venturi feeder, a feed inlet of the Venturi feeder is connected with a feed hopper through a second material conveying pipeline, and a discharging device is arranged on the feed hopper; the discharging device comprises a spiral discharger, a weighing hopper, a storage bin and a motor; the spiral discharger is arranged on the weighing device, the weighing hopper is connected with the spiral discharger, the storage bin is connected with the weighing hopper through a soft connecting device, a quick feeding valve is arranged on the soft connecting device, the motor is connected with the spiral discharger through a magnetic coupling, and the motor is connected with a motor controller;

the air inlet of the venturi feeder is connected with the air supply device, the air supply device comprises a fan and an air pressure stabilizing tank which are sequentially connected through an air pipe, the outlet of the fan is connected with the inlet of the air pressure stabilizing tank, a fan valve is arranged between the outlet of the air pressure stabilizing tank and the air inlet of the venturi feeder, and the air pressure stabilizing tank is connected with an automatic exhaust valve through an air pipe;

the data processor comprises a first data processor and a second data processor, the first data processor is connected with the weighing device, the data collector is respectively connected with the first data processor and the solid flowmeter to be detected, and the second data processor is connected with the data collector;

and the discharge port of the first material conveying pipeline is connected with a powder recovery device.

2. The solids flow meter accuracy detection system of claim 1, wherein: and a material level meter is arranged on the weighing hopper and is respectively connected with the quick feeding valve, the alarm device and the motor controller.

3. The solids flow meter accuracy detection system of claim 2, wherein: the distance between the solid flowmeter to be detected and the Venturi feeder and the distance between the solid flowmeter to be detected and the powder recovery device are both 5-8 times of the diameter of the first material conveying pipeline.

4. The solids flow meter accuracy detection system of claim 3, wherein: the feed opening of spiral discharger stretches into downwards in the feeder hopper, the feed opening of spiral discharger with the feeder hopper contactless is connected.

5. The solids flow meter accuracy detection system of claim 4, wherein: and a gas flowmeter is arranged on the air pipe connecting the fan valve and the venturi feeder.

6. The solids flow meter accuracy detection system of claim 5, wherein: the first material conveying pipeline is provided with a transparent window, and the transparent window is arranged between the solid flow meter and the powder recovery device.

7. The solids flow meter accuracy detection system of claims 1-6, wherein: the powder recovery device comprises a cyclone dust collector, an electrostatic dust collector and a recovery hopper, wherein an inlet of the cyclone dust collector is connected with a discharge port of a first material conveying pipeline, a discharge port of the cyclone dust collector is connected with a first inlet of a discharge pipeline, an air outlet of the cyclone dust collector is connected with an inlet of the electrostatic dust collector, a discharge port of the electrostatic dust collector is connected with a second inlet of the discharge pipeline, and an outlet of the discharge pipeline is connected with the recovery hopper.

8. A method for detecting the accuracy of a solid flow meter is characterized by comprising the following steps: comprising using the solids flow meter accuracy detection system of claim 7 above;

setting a discharging device to provide a stable and accurately measured powder discharging mass flow, wherein the powder discharging mass flow is set according to the range of a solid flowmeter to be detected, so that powder flows through a first conveying pipeline provided with the solid flowmeter under the action of wind;

adjusting the air quantity of the air supply device until the powder does not deposit in the first conveying pipeline and is in a stable pneumatic conveying state;

when the powder is in a stable pneumatic conveying state in the first conveying pipeline, the accuracy of the solid flowmeter to be detected is the percentage of the mass flow of the powder in the first conveying pipeline detected by the solid flowmeter at the moment and the powder discharging mass flow of the discharging device measured and calculated by the first data processor.

9. The method of detecting accuracy of a solid state flow meter of claim 8, wherein:

the height of powder in the weighing hopper is detected through the material level indicator, when the lower limit of the material level is reached, the material level indicator simultaneously sends signals to the quick feeding valve, the alarm device and the motor controller, the quick feeding valve starts feeding materials, the alarm device gives an alarm, and the motor controller controls the motor to be closed; when the material level height in the weighing hopper reaches the upper limit of the material level, the material level meter sends signals to the quick feed valve, the alarm device and the motor controller simultaneously, the quick feed valve is closed to stop feeding, the alarm device gives an alarm, and the motor controller controls the motor to start.

10. The method of detecting accuracy of a solid state flow meter of claim 9, wherein: after the mass flow of the discharged powder is adjusted through the motor controller, the air quantity is readjusted until no deposition phenomenon of the powder in the first material conveying pipeline is observed from the transparent window and the powder is in a new stable pneumatic conveying state, and then the accuracy of the solid flow meter is detected.

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