A differential pressure flow meter uses a pressure-reducing orifice to create a difference between upstream and downstream pressure. According to Bernoulli's law, the volumetric flow is proportional to the pressure gradient.
This is the most common of all flow meters in water treatment plants and in the chemical, petrochemical and gas industries.
Diaphragm, venturi and nozzle are the three primary types of differential pressure flow meters. They are designed in accordance with recognized flow/pressure ratio standards (ISO 5167 in Europe). They use a differential pressure unit linked to an upstream and a downstream sensor. A signal transmitter and a calculator send the reading to a display or to a control mechanism.
The diaphragm version is the most common, but it cannot be used with turbid liquids because particles tend to accumulate at its base, leading to significant energy losses. Nozzle and venturi meters use a progressive constriction. The former has an abrupt exit point, while the latter uses a gradual configuration. They are better able to measure the flow of slurries and viscous liquids. Venturis are accurate, show little energy loss and reduced wear and dirt build-up. However, they are expensive and bulky.
Pitot tubes, target and U-bend flow meters use similar principles of operation.
Choice will depend on the nature of the fluid, available upstream and downstream space and energy loss.
- Standardized parameters
- Simple maintenance
- Energy loss
- Limited rangeability
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Differential pressure flow-meter TESTO
The digital manifold for service and maintenance incl. clamp probe, calibration protocol and batteries testo 550: just switch on, measure, and read off Large figures allow the values to be read off the display quickly and easily. Two temperature-compensated pressure...
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Differential pressure orifice flow-meter DN 25 - 1000 | Deltatop DO62C ENDRESS HAUSER
selectable according to the application - operational compact version - modular remote version optimized for minimum pressure loss, highest accuracy and maximum measuring dynamics...
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Differential pressure orifice flow-meter FPD500 ABB Measurement Products
Compact Orifice FlowMeter OriMaster is a Compact Orifice Flowmeter that combines a wafer-mounted orifice carrier, integral manifold and transmitter into a single, fully-codable, orifice-based flowmeter. OriMaster is supplied...
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Air-gas differential pressure flow-meter Fluke 922 FLUKE
Analyze airflow. Easily. The 922 Micromanometer. Today’s HVAC technicians want a simple solution for diagnosing ventilation issues. Differential pressure measurements only tell part of the story. Technicians also...
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Differential pressure flow-meter Spirax Sarco
Orifice plates are still the most widely used type of flowmeter today, offering;...
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Differential pressure orifice flow-meter OP/PE/TE series DWYER
The Series OP Orifice Plate Flowmeter is a complete orifice plate flow metering package. It incorporates a stainless steel orifice plate with a unique holder or carrier...
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Differential pressure flow-meter for gas, steam and liquid deltaflow DF8 systec Controls
deltaflow biogas flowmeter Biogas is a valuable source of energy in waste water plants and bio power plants. The precise and reliable flow measurement is a difficult application with very special requirements to the flow meter. Low pressure loss Insensitivity to particles and foam Free condensate drainage High accuracy short straight...
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Differential pressure flow-meter +/- 0.1 Pa, 0.001 in. H2O | Zephyr II GrayWolf Sensing Solutions
Differential pressure measurement is a crucial parameter for determining pollutant pathways for IAQ and worker exposure applications. It is also a key HVAC parameter in commercial and institutional buildings and in manufacturing plants, among many other important applications. Each Zephyr II instrument includes a built-in, auto-zeroing, micro-manometer and 'K'-type thermocouple input for measuring...
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Differential pressure orifice flow-meter F O Turbo-Lux 2 MECON GmbH
Orifice plate flowmeter F O Turbo-Lux 2 : The F O Turbo-Lux 2 orifice plate flowmeter consists of a differential pressure sensor for stationary installation, and a portable...
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Pitot tube differential pressure flow-meter VAP³® series Eastern Instruments
Eastern Instruments' VAP3® Pitots have a unique Velocity Averaging and Parallel Plate proprietary design. When inserted in air flow ducts, the VAP3® Pitots provide an accurate, differential pressure output allowing for precise air flow measurement or control of your process. VAP3® Pitots are designed for Superior Accuracy (SA) for clean air applications...
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Differential pressure mass flow-meter 0 - 20 Pa / 0 - 100 Pa | PascalSwitch Novasina AG
Differential pressure instrument PascalSwitch 20 / 100 - Long term stability and high accuracy - No detectable hysteresis - Resistant to overpressure up to 2 bar - 2 selectable alarm thresholds...
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Venturi differential pressure flow-meter MVR/FVR Arthur Grillo GmbH
The venturi tube MVR/FVR is a primary element for flow metering in tubings. The principle of the venturi tube allows for meterings with all media. The venturi tube described here is especially designed for air flow metering in ventilation channels. Mounting of the venturi tube in the installation has to be made using plug sockets with the...
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The material for throttling device is as followed without special requirements 1、Throttling element: 1Cr18Ni9Ti...
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Air-gas differential pressure flow-meter Flowtest ST TECORA
Compatible with the majority of Pitot...
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Venturi differential pressure flow-meter Golden Mountain Enterprise
ISO 5167-4 Standard Beta Ratio ß:0.3~0.75 Minimum Reommended...
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Near the activation basin the pressure loss at the membrane is determined by differential measurement. It is possible to design the measuring head to be fixed or maneuverable so that measurements can be taken in several places,...
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Venturi differential pressure flow-meter APLITEX, S.L.
CHARACTERISTICS Classic Venturi Tube for welding to pipe or mounting between flanges. Execution conform to DIN or ASA. Construction from welded sheet or forged bar. Consisting of a short cylindrical section,...
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Differential pressure flow-meter D-FL 100 DURAG
Volume Flow Measuring System D-FL 100 Measuring system to measure flow rate in dry emissions with a probe using the differential pressure principle Features Measurement...
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Differential pressure flow-meter 1120 Series Meriam Instrument
The Meriam Model 1120 Differential Pressure Unit is a proven and reliable sensing element used in all Meriam Bellows Gauges. It is available in ranges as low as 0-30" w.c. or as high as 0-500 PSI. The light weight and compact differential pressure unit incorporates a rupture-proof and leak-proof bellows...
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Differential pressure flow-meter max. 180 psig | 7000, 8000 series Clark
Use the 7000/8000 series flow meters for measuring the flow rate of liquids, gases, compressed air and steam in closed pipes. We also make indicating flow switches and flow transmitters for process indication and control. Meters feature a large easy to read analog dial with 270 degree pointer movement. Our flow meters are suited to a wide range...
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Differential pressure flow-meter PG 2 - 6 series Watts Water Technologies
Series PG-2, 3, 4, 5, and 6 Differential Pressure Meters are kits designed to measure differential pressures on flow measurement valves and flow...
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Differential pressure flow-meter max. 350 °C, 20 - 1000 l/min | DFM4 Series SINGLE Temperiertechnik
DFM4 series Flow Meters SINGLE’s DFM4 flow meter provides reliable monitoring and alarm functions for optimizing temperature control processes in plastics processing, chemical and...
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• Flow measurement of mineral oils such as heating or propellant fuels • In burners, on board ships, land vehicles and fixed installations • Marine and metrological...
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Differential pressure flow-meter max. 180 psig | 7000, 8000 series Clark
Use the 7000/8000 series flow meters for measuring the flow rate of liquids, gases, compressed air and steam in closed pipes. We also make indicating flow switches and flow transmitters for process indication and control. Meters feature a large easy to read analog dial with 270 degree pointer movement. Our flow meters are suited to a wide range...
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Differential pressure orifice flow-meter 2 - 12" | 3051SFC Rosemount
Rosemount Conditioning Orifice Flowmeter technology provides unprecedented performance with minimal straight-run piping. Orifice metering is now more flexible and better than ever before. Rosemount Conditioning Orifice...
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Differential pressure orifice flow-meter Z6 Asa
MODEL Z6 Among the advantages of kinetic Asameters for water there are: - low cost like no other variable area flowmeter - the scale linearity that grants good measurements even at low flowrates - an excellent accuracy of measurement, granted...
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Differential pressure orifice flow-meter 10 - 50 bar | M3 series Eletta Flow AB
M3 - Flow Meter measuring Gas, Liquid flow and DP: M3-series from Eletta is a unique product. Three modes in one instrument: Gas, Liquid and Differential Pressure. The well-documented differential pressure measuring principle with exchangeable orifice-plates is...
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Differential pressure orifice flow-meter pr62, pr25 TECFLUID
Measurement of Flow from an Orifice Plate • Measurement of full flow, indirectly with an orifice plate and VA flowmeter. • Construction in all PVC,...
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V-cone differential pressure flow-meter McCrometer
The V-Cone Flow Meter is an advanced differential pressure instrument, which is ideal for use with liquid, steam or gas media in rugged conditions where accuracy, low maintenance and cost are important. With its DP built-in flow conditioning design,...
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Differential pressure flow-meter for gas, steam and liquid HDM-250 Shortridge Instruments, Inc
HYDRODATA MULTIMETER HDM-250 The HydroData Multimeter is accurate across an extremely broad range of fluid gage pressures and differential pressures. The high pressures existing at pumps, chillers, cooling towers, and high rise building conditions can be...
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Air-gas differential pressure flow-meter max. 2 psi | Model 269 SETRA
Overview Designed for high performance applications such as those found in critical medical and pharmaceutical environments. This unit is offered in a din rail or base mount version and features easy to access pressure ports and electrical connections. Pressure ranges are available in ranges as low...
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Air-gas differential pressure flow-meter MF-PD ver 3 Micatrone AB
Micaflex Air Flow transmitter type MF-FD Differential pressure transmitter with flow linear output MF-FD ver 3 is a flow linear differential pressure transmitter...
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Differential pressure fuel flow-meter 0 - 10 g/s | FX-1110 Onosokki
The FX Series gravity flow detectors employ a precision differential pressure transducer to detect liquid level variations in a measuring cylinder....
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Venturi differential pressure flow-meter PRESO
Preso manufactures 3 types of Venturi flow meters, to meet a variety of application and budgetary requirements, inlcuding classical,...
