CN201237513Y - Integrated intelligent differential pressure type mass flowmeter - Google Patents
Integrated intelligent differential pressure type mass flowmeter Download PDFInfo
- Publication number
- CN201237513Y CN201237513Y CNU2008201477164U CN200820147716U CN201237513Y CN 201237513 Y CN201237513 Y CN 201237513Y CN U2008201477164 U CNU2008201477164 U CN U2008201477164U CN 200820147716 U CN200820147716 U CN 200820147716U CN 201237513 Y CN201237513 Y CN 201237513Y
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Abstract
The utility model belongs to the technical field of fluid flow measurement. The provided integrated intelligent differential pressure mass flow meter essentially comprises a double-cone throttling device, a compound sensor and a micro processor display output unit; the compound sensor comprises a measuring circuit essentially consisting of two high-precision pressure sensing elements and a signal processing unit; wherein, the double-cone throttling device and the measuring circuit essentially consisting of two pressure sensing elements (7) and (8) form a primary part which is used to collect parameters of fluid flow, pressure and the like; the signal processing unit of the compound sensor and the micro processor display output unit form a secondary part of the mass flow meter; the secondary part is also provided with a power supply unit (17); the signal processing unit is used to conduct conditioning and setting, amplification and A/D conversion to the signal collected by the primary part; the micro processor and the display output unit are used to carry out operation, display output and fault judgment to the converted digital signal.
Description
Technical field
The utility model belongs to fluid flux measurement technology, mainly proposes a kind of integrated intelligent differential pressure type quality flow meter.
Background technology
At present, industrial most widely used Flow Measuring System mainly is to join differential pressure transmitter, flow integrator based on conventional throttle devices such as orifice plate, nozzle, Venturi tubes.Their ubiquities to the front and back flow development length require high, crushing is big, precision is low, measurement range degree (range ratio) is little, outflow system is unstable, shortcomings such as easily contamination, maintenance be big before and after the throttling element when surveying dirty fluid, has seriously restricted its application in a lot of fields.
At above shortcoming, manufacturer has all carried out relevant improvement, research one after another with the fluid operating person both at home and abroad.At present, technological improvement mainly divides two aspects: the improvement of structural improvement and measuring system.For the former, multiple novel throttling element has been proposed both at home and abroad one after another, as annular orifice, internal cone type restriction device is V awl restriction device) etc., they have certain improvement to the shortcoming of conventional throttle device, but have some shortcomings, big as crushing, precision is low, measurement range degree (range ratio) is little etc.Improvement for measuring system:, the measurement pattern that the multiparameter mass flow transmitter combines with the conventional throttle device occurred at home and abroad.The multiparameter mass flow transmitter possesses the function of measuring differential pressure, pressure, temperature course parameter simultaneously, by perform calculations from static preset physical parameter values such as the configuration software that in microprocessor, is provided with and the density in the physical characteristic data storehouse, concentration, humidity outflow and show, output, collection process measuring instrument and flow totalizer meter and the whole body.Its appearance is a much progress of differential pressure type flow instrument, has reduced process measuring instrument quantity, and advanced technology and realized incorporate structure but also have the drawback of conventional throttle device still exists as the defective of pressure guiding pipe wire system.
The traditional measurement differential pressure is to adopt the differential capacitance type differential pressure transmitter mostly, its principle is: the pressurized membrance electrode is between two fixed electordes, constitute two capacitors, the pressure of diverse location is introduced to two of differential pressure transmitter and is subjected to pressuring film plate, increase another then corresponding reducing in the next capacitor volume of the effect of pressure, measurement result is exported by the differential type circuit.Fixed electorde is a metal cladding and making on the glass surface of recessed song.Diaphragm is subjected to the protection of concave surface and unlikely breaking during overload.The differential capacitance type pressure transducer is highly sensitive, the linearity good (differential capacitor of two electric capacity formations makes and eliminated many steps on calculating), but processing is difficulty (particularly being difficult to guarantee symmetry), and owing to be subjected to pressuring film plate to be necessary for metallic membrane, can not realize isolation to tested gas or liquid, therefore be unsuitable for be operated in be corrosive, in the fluid of impure or high temperature.And when measuring high temperature or Korrosionsmedium, must adopt long impulse pipeline cooling and isolation.Its measurement range degree (ratio that is limited to measurement lower limit in the measurement) is little, and 40:1 is generally only arranged, and surpasses this scope, and precision just sharply descends.And when it and restriction device conjunction measuring flow,, therefore cause the orientation degree of flow measurement narrower because flow presents quadratic relationship with differential pressure, it is very inapplicable to measure occasions at many degree on a large scale.It has advantage highly sensitive, that the linearity is good, has obtained widely using but it also has rangeability narrow simultaneously in various industrial occasions, to the processing request height, can not realize with measuring media isolatedly, can not the shortcoming of working under the environment such as burn into high temperature arranged.
Summary of the invention
The fundamental purpose that the utility model proposes a kind of integrated intelligent differential pressure type quality flow meter guarantees that still it has higher measuring accuracy when promptly being to make its measurement range degree with broad.
Another purpose of the present utility model is to guarantee measuring stability, and makes it can be used for measuring various dirty fluids.
The purpose of this utility model also be to overcome traditional differential pressure flowmeter to physical properties of fluids measurement requirement height such as density, shortcoming such as compensation way is single, stiff at present.
The utility model adopts following technical proposals to finish its invention task: a kind of integrated intelligent differential pressure type quality flow meter mainly comprises biconial restriction device, compound sensor and microprocessor and shows output unit; Compound sensor comprises metering circuit and the signal processing unit that mainly is made of two high-precision pressure sensing elements; Wherein, by the biconial restriction device and the metering circuit of mainly forming by two pressure sensors constitute once part, the process variables such as flow, pressure that are used for convection cell are collected; The secondary part that constitutes mass flowmeter by signal processing unit and microprocessor, the demonstration output unit of compound sensor, signal processing unit be used for the signal that collected of part once nursed one's health adjust, processing and amplifying and A/D conversion, microprocessor and show that output unit is used to realize to carrying out calculation process through the digital signal of conversion, showing functions such as output, fault judgement.
In the utility model, the biconial restriction device comprises measuring tube and is arranged on the interior biconial throttling element of measuring tube, the generation of flow signal is produced by the effect of damming of biconial throttling element convection cell, promptly when fluid flows through the biconial throttling element, be subjected to the tapering type throttling action of biconial throttling element limit wall, flow velocity can increase and static pressure can reduce, and by the pressure sensor that is directly installed on the table body pressure is measured.
One of them pressure sensor is arranged on the measuring tube of biconial restriction device and is positioned at the front portion of biconial throttling element; Another pressure sensor is arranged on the measuring tube of biconial restriction device and is positioned at and the corresponding position of right cylinder, biconial throttling element middle part.
Microprocessor has peripheral interface, in order to connect densimeter, densitometer and other rerum natura instrument.
In the utility model, once the biconial restriction device that adopted of part has Stability Analysis of Structures, not easy to wear, long-time stability good, signal accuracy is high and crushing is little characteristics, can produce high-quality flow signal.Compound sensor is made up of two high-precision pressure sensing elements that are installed in diverse location on the measuring channel and signal processing unit, has measuring accuracy height, compact conformation, can operate as normal under corrosion or the hot environment arranged, need not to isolate and realize integrated easily.The selected signal processing unit of secondary part can be nursed one's health the signal that compound sensor is gathered and adjust, processing and amplifying and A/D conversion, is converted into digital signal, so that carry out high-accuracy arithmetic.Microprocessor will utilize the software of systemic presupposition to carry out various computings by the digital signal of conversion, draw differential pressure value, static pressure equivalence; Just can draw mass rate by the differential pressure type mass flow mathematical model that is preset in the storer in the system software, deliver to display unit again, demonstrate various information, can also carry out self diagnosis instrument system.
The utlity model has following advantage:
1, utilizes brand-new differential pressure measurement principle, promptly utilize the compound sensor gaging pressure, and draw differential pressure, have compact conformation, can the advantage of operate as normal under corrosion or the hot environment arranged, overcome the little shortcoming of rangeability of traditional differential capacitance type differential pressure transmitter, keeping under the constant situation of precision, widened rangeability greatly, therefore make existing dirty, the durable advantage that bears dirty of integrated differential-pressure-type mass flowmeter, degree of accuracy height, rangeability are big again, have broken differential pressure flowmeter and have been not suitable for convention in Wide-range flow applications.Adopt two pressure transducers to carry out differential pressure measurement, the principle of employing is to measure the pressure of diverse location respectively by two pressure transducers, is converted into electric signal, delivers to microprocessor again and carries out additive operation and draw differential pressure.The advantage of this method is that its measurement range degree is very wide because pressure transducer is not because the difference of measuring principle has the influence of measurement range degree, so and during restricting element conjunction measuring flow, can reach very wide measurement range.In addition, pressure resistance type measuring principle according to pressure transducer, be that resistance value can change behind its sensing element pressurized, that uses at present mostly is ceramic pressure sensor greatly, has high temperature resistant, corrosion-resistant, shock proof advantage, when measuring the fluid of corrosivity, impure or high temperature, need not to isolate.But the shortcoming that adopts this method to measure differential pressure is that two pressure transducers are difficult to keep consistency of performance, as the zero drift size and Orientation, to such an extent as to influence the stability of circuit, thus cause error to increase.
The utility model adopts compound sensor and restriction device conjunction measuring flow, combines the advantage of traditional differential capacitance type differential pressure transmitter and pressure resistance type pressure unit, has overcome their shortcoming again.Its principle is with two ceramic pressure sensing elements, utilizes the Wheatstone bridge principle, is positioned in the middle of the circuit, forms a sensor.And there is reference voltage as a reference.In a single day the performance of each sensing element changes, and the entire circuit state will change, and changes to be sent in the microprocessor, after comparing with reference voltage, carries out corresponding compensation, to guarantee measuring accuracy.Because the ceramic pressure sensing element that adopted has high temperature resistantly, corrosion-resistant, shock proof advantage need not long impulse pipeline cooling when measuring high-temperature medium, also need not when measuring Korrosionsmedium to isolate, and has reduced the workload of construction and maintenance in addition.
2, on structure, throttling element, table body, pressure, differential pressure, three kinds of sensors of temperature, signal Processing arithmetic element, demonstration output unit are integrated in the flowmeter, compact conformation, volume are little, convenient for installation and maintenance simple, have realized real integrated.On function, it participates in computing to flow measurement, compensation operation, external parameter and combines, and can all multifactorly carry out online dynamics compensation operation to what influence the flow measurement precision, also can accept precise information from peripheral instrument, measure accurately, error is little, the reliability height.
3, the employing external world powers and carries battery powered mode, and the user can select as required flexibly, and is easy to use.
Description of drawings
Fig. 1 is a structural representation of the present utility model.
Fig. 2 is the model structural representation of another kind of band of the present utility model temperature compensation.
Fig. 3 is the front schematic view of gauge outfit in the utility model.
Fig. 4 is the side schematic view of gauge outfit in the utility model.
Fig. 5 is the preceding A of operating room-A sectional view of Fig. 4.
Fig. 6 is the back B of operating room-B sectional view of Fig. 4.
Fig. 7 is the circuit diagram of compound sensor metering circuit.
Among the figure, 1, measuring tube, 2, the biconial throttling element, 3, positive pressure tappings, 4, negative pressure tappings, 5,6, pressure measuring valve, 7 and 8, high-precision pressure sensor, 9, temperature sensors of high precision, 10, fairlead, 11, gauge outfit, 12, signal processing unit, 13, microprocessor, 14, show output unit, 15, LCD display, 16, keyboard, 17, power supply unit, 18, connection terminal, 19, battery, 20, support.
Embodiment
The embodiment that provides with reference to the accompanying drawings is illustrated the utility model:
As shown in Figure 1, the utility model is by once part and secondary are partly formed.Once part comprises biconial restriction device and compound sensor.Compound sensor comprises main by two high-precision pressure sensing elements 7 and 8 metering circuits that constitute and signal processing unit 12; Two high-precision pressure sensing elements 7 and 8 by pressure measuring valve 5 and 6 and be installed on the measuring tube 1 of biconial restriction device, are provided with positive pressure tappings 3 and negative pressure tappings 4 respectively on measuring tube 1; Wherein high-precision pressure sensing element 6 is connected with pressure measuring valve 5 on being installed in positive pressure tappings 3, high-precision pressure sensing element 7 be installed in negative pressure tappings on 4 pressure measuring valve 6 be connected.Wherein positive pressure tappings 3 is positioned at the position of the front portion of biconial throttling element 2 on the measuring tube 1, and negative pressure tappings 4 is positioned on the measuring tube 1 and the corresponding position of biconial throttling element 2 middle part right cylinders.Support 20 is arranged on measuring tube 1, and support 20 upper ends are fixed with gauge outfit 11,11 li signal processing unit 12, microprocessor 13, demonstration output units 14 that compound sensor is installed of gauge outfit.High-precision pressure sensing element 7 and 8, temperature sensor 9 are connected by the input end of the signal processing unit 12 of 11 li of fairlead 10 and gauge outfits.
The biconial restriction device comprises measuring tube 1 and biconial throttling element 2, has positive pressure tappings 3 and negative pressure tappings 4 on the measuring tube.The axis coaxle of the axis of measuring tube 1 and biconial throttling element 2, the axis normal of positive pressure tappings 3 and negative pressure tappings 4 and biconial throttling element 2.The cylindrical equal diameters of the maximum gauge of the front and back cone of biconial throttling element 2 and middle part, the tapering of precentrum is greater than the tapering of posterior pyramids.Positive pressure tappings 3 and the center line of negative pressure tappings 4 and the axis normal of measuring tube 1, positive pressure tappings 3 and negative pressure tappings 4 are equiped with pressure measuring valve 5 and pressure measuring valve 6 respectively.One end of pressure measuring valve is connected with the high-precision pressure sensing element, and the other end is installed on the pressure tappings.
In the utility model, the secondary part mainly is made up of microprocessor 13, demonstration output unit 14, also has power supply unit 17.Wherein microprocessor 13, show output unit 14 and once in the part signal processing unit 12 1 of compound sensor be located in the preceding operating room of gauge outfit 11, power supply unit 17 is positioned in the back operating room of gauge outfit 11.The input end of microprocessor 13 is connected with the signal processing unit of compound sensor 12, and output terminal is connected with demonstration output unit 14.Demonstration output unit 13 is made up of display module (LCD display 14) and load module 15.Power supply unit 17 in the back operating room is built-in with connection terminal 18 and battery 19, and connection terminal 18 can connect the external power power supply; Back operating room also is provided with other connection terminal and constitutes peripheral interface.
As shown in Figure 2, on measuring tube 1 biconial throttling element 2 rear portions the position temperature sensor 9 is installed, be used for when measurement gas or steam, carrying out temperature detection, its measured value is sent into and is carried out the temperature compensation computing in the microprocessor.Temperature sensor 9 is connected by the microprocessor of 11 li of spool 10 and gauge outfits.
When fluid flows through the measuring tube 1 of biconial restriction device, be subjected to the throttling action of biconial throttling element 2, fluid is forced in biconial throttling element 2 place's a fluid streams and shrinks, thereby fluid is quickened, static pressure reduces, dead ahead and mediate cylindrical place at biconial throttling element 2 produce pressure differential, utilize Bernoulli's theorem and mobile continuity equation just can record flow.
The utility model when work, the fluid measuring tube 1 of flowing through, high-precision pressure sensing element 7 is used for the pressure of test fluid, and high-precision pressure sensing element 8 is used to detect the pressure through the fluid after the throttling action.These two pressure signals are sent to the signal processing unit 12 of compound sensor, adjust through the conditioning of signal conditioning circuit, and the entering signal amplifier carries out processing and amplifying and A/D conversion again, is converted into the higher digital signal of precision.This digital signal is sent into 13 li of microprocessors again, draw force value, draw differential pressure value by the difference of trying to achieve two pressure again, utilize the differential pressure type mass flow mathematical model that is preset in the storer in the system software just can draw mass rate, deliver to again and show output unit 14, can be in information such as the differential pressure that demonstrates instantaneous delivery, integrated flux, fluid on the LCD display on 15, pressure, can also utilize the load module (being keypad 16) that shows output unit 14 to flow and be provided with in detail simultaneously.Signal processing unit is nursed one's health voltage signal and is adjusted, and carries out processing and amplifying and A/D conversion again, is converted to the higher digital signal of precision, for existing mature technology, does not do too much explanation at this.When flowmeter broke down, microprocessor 13 can also carry out self diagnosis to the various piece of instrument, and various failure codes realized self-diagnostic function showing on 15 on the LCD display.The output module that shows output unit 14 can output to the digital signal output of process variable with 4-20mA current signal and stack thereon on Displaying Meter or the industrial computer.Also can export digital both-way communication signal in addition, utilize long-range terminal console or handheld terminal that it is carried out configuration, parameter setting or modification.In addition, demonstration output unit 14 can also be accepted the signal of various peripherals, and as densitometer, densimeter etc., the accurate measured value that receives them participates in the middle of the flow computing, to improve operational precision.
When measuring media was gas or steam, the course of work was same as described above, just send into the signal of microprocessor many a temperature signal, participate in the temperature pressure compensation computing.
Metering circuit explanation in the compound sensor: as shown in Figure 7, in this circuit, two high-precision pressure sensing elements and two other resistance have been formed a Wheatstone bridge, and this electric bridge and other element have been formed a loop.Get under the condition in 5V direct current supply, when the pressure sensor pressurized, its resistance can change, thereby the entire circuit state is changed, this variation is used as millivolt signal, through signal condition, adjust, it is carried out delivering to after the filtering signal amplifier carry out processing and amplifying and A/D conversion, be converted into the higher digital signal of precision, this digital signal is sent into and is carried out related operation in the microprocessor.This circuit also has a voltage reference as a reference simultaneously, by the parameter reference with resistance 7,8 (being the high-precision pressure sensing element).When their performance changes, after contrasting, its voltage status and reference voltage send into microprocessor, can carry out corresponding operation processing, the measuring error that changes and brought with compensation performance.
Claims (5)
1, a kind of integrated intelligent differential pressure type quality flow meter is characterized in that: mainly comprise biconial restriction device, compound sensor and microprocessor display output unit; Compound sensor comprises metering circuit and the signal processing unit that mainly is made of two high-precision pressure sensing elements; Wherein, constitute once part by biconial restriction device and the metering circuit mainly be made up of two pressure sensors (7), (8), the process variable such as flow, pressure that is used for convection cell is collected; The secondary part that constitutes mass flowmeter by signal processing unit and microprocessor, the demonstration output unit of compound sensor, the secondary part also has power supply unit (17), signal processing unit be used for the signal that collected of part once nursed one's health adjust, processing and amplifying and A/D conversion, microprocessor and show that output unit is used to realize to carrying out calculation process through the digital signal of conversion, showing output, fault judgement.
2, integrated intelligent differential pressure type quality flow meter according to claim 1 is characterized in that: the front portion of biconial throttling element (2) is gone up and be positioned to the measuring tube (1) that one of them pressure sensor of described pressure sensor (7) is arranged on the biconial restriction device; The measuring tube (1) that another pressure sensor (8) is arranged on the biconial restriction device is gone up and is positioned at and the corresponding position of right cylinder, biconial throttling element middle part.
3, integrated intelligent differential pressure type quality flow meter according to claim 1 is characterized in that: the periphery that described microprocessor has in order to connect densimeter, densitometer and other rerum natura instrument is provided with interface.
4, integrated intelligent differential pressure type quality flow meter according to claim 1, it is characterized in that: once the biconial restriction device in the part comprises measuring tube (1) and biconial throttling element (2), the axis coaxle of the axis of measuring tube (1) and biconial throttling element (2); The cylindrical equal diameters of the maximum gauge of the front and back cone of biconial throttling element (2) and middle part, the tapering of precentrum is greater than the tapering of posterior pyramids; On measuring tube (1), be provided with positive pressure tappings (3) and negative pressure tappings (4), positive pressure tappings (3) and the center line of negative pressure tappings (4) and the axis normal of measuring tube (1), positive pressure tappings (3) and negative pressure tappings (4) are equiped with pressure measuring valve (5) and pressure measuring valve (6) respectively; One end of pressure measuring valve (5) is connected with high-precision pressure sensing element (7), and the other end is installed on the positive pressure tappings (3); One end of pressure measuring valve (6) is connected with high-precision pressure sensing element (8), and the other end is installed on the positive pressure tappings (4).
5, integrated intelligent differential pressure type quality flow meter according to claim 1, it is characterized in that: the microprocessor (13) in the secondary part, show output unit (14) and once the signal processing unit (12) of the compound sensor in partly be located in the preceding operating room of gauge outfit (11), power supply unit (17) is positioned in the back operating room of gauge outfit (11); The signal processing unit (12) of the input end of microprocessor (13) and compound sensor is connected, and output terminal is connected with demonstration output unit (14); Demonstration output unit (14) is made up of display module, LCD display and output module; Power supply unit in the back operating room (17) is built-in with battery (18) and connection terminal (19), and connection terminal (19) both can connect external power and carry out direct current 24V power supply, also can other peripherals received signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201477164U CN201237513Y (en) | 2008-06-30 | 2008-06-30 | Integrated intelligent differential pressure type mass flowmeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201477164U CN201237513Y (en) | 2008-06-30 | 2008-06-30 | Integrated intelligent differential pressure type mass flowmeter |
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| Publication Number | Publication Date |
|---|---|
| CN201237513Y true CN201237513Y (en) | 2009-05-13 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNU2008201477164U Expired - Fee Related CN201237513Y (en) | 2008-06-30 | 2008-06-30 | Integrated intelligent differential pressure type mass flowmeter |
Country Status (1)
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| CN (1) | CN201237513Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102003983A (en) * | 2010-12-09 | 2011-04-06 | 沈阳北星仪表制造有限公司 | Intelligent differential pressure balancing flowmeter |
| CN103822676A (en) * | 2014-03-07 | 2014-05-28 | 中国计量学院 | Gas-liquid two-phase flow measuring device adopting double-cone flow rate meter and assistant relevant ultrasonic flow rate meter |
-
2008
- 2008-06-30 CN CNU2008201477164U patent/CN201237513Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102003983A (en) * | 2010-12-09 | 2011-04-06 | 沈阳北星仪表制造有限公司 | Intelligent differential pressure balancing flowmeter |
| CN103822676A (en) * | 2014-03-07 | 2014-05-28 | 中国计量学院 | Gas-liquid two-phase flow measuring device adopting double-cone flow rate meter and assistant relevant ultrasonic flow rate meter |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090513 |