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Exploring Flow Meter Technology

Exploring Flow Meter Technology

Flow meter technology plays a crucial role in various industries, providing accurate measurements of fluid flow rates. These devices, designed to measure the rate of flow of liquids or gases, come in various forms, each tailored to specific applications. But how do these work? Let's explore the inner workings of paddlewheel, turbine, ultrasonic, and oval gear flow meters, shedding light on their distinct features. 

Paddlewheel Flow Meters

Paddlewheel flow meters are mechanical meters with a freely rotating paddlewheel set in the path of a fluid stream. As the fluid pushes against the blades, the wheel rotates at a speed proportional to the flow rate. By measuring this rotational speed, the flow rate can be accurately determined. 

Paddlewheel flow meters are known for their simplicity, cost-effectiveness, and reliability, making them ideal for application where moderate accuracy is sufficient. 

  • Measure the flow of water, fuel, and other low viscosity liquids
  • Extremely versatile; suited for a huge variety of pipe sizes
  • Only one moving part; provides a reliable product with minimal maintenance costs
  • Exceptional measurement accuracy
Suits Pipe Sizes 1.5 - 100" (40 - 2500 mm)
Flow Range*  3 - 33 fps (1-10 m/s)
Accuracy* ± 1.5% of Reading
Temperature Range* -40°F to 300°F (-40°C to 150°C)
Operating Pressure* 1160 psi (80 bar)

* Ranges vary depending on meter, material, and size

View PADDLEWHEEL insertion flow meter

Turbine Flow Meters

Turbine flow meters use the mechanical energy of the fluid to rotate a "pinwheel" (rotor) in the flow stream. Blades on the rotor are angled to transform energy from the flow stream into rotational energy. The rotor shaft spins on bearings. When the fluid moves faster, the rotor spins proportionally faster. 

Turbine flow meters excel in applications requiring high accuracy and wide flow range capabilities.

  • Extremely versatile design accurately measures high and low viscosity fluids
  • High accuracy and repeatability measures every drop and saves waste in your process
Suits Pipe Sizes 1/2" - 4" (15 - 101 mm)
Flow Range* 3.8 - 1135 L/min
Accuracy* ± 1.5% - 5% of Reading
Temperature Range* -40°F to 250°F (-40°C to 121°C)
Operating Pressure* 150 psi (10.3 bar) - 300 psi (21 bar)

* Ranges vary depending on meter, material, and size

View TURBINE flow meters

Ultrasonic Flow Meters

Ultrasonic flow meters transmit and receive a burst of ultrasound between two transducers. Transit time is measured in both directions. By analyzing the time it takes for the pulses to travel upstream and downstream, the velocity of the fluid can be calculated with exceptional accuracy. Since there are no moving parts required to detect flow, it continues to measure accurately in low-flow situations. 

  • Easy installation
  • No moving, wearable parts; low-to-zero maintenance
  • Low total cost of ownership
  • High accuracy and repeatability, measures every drop and saves waste in your process
Suits Pipe Sizes 1 - 12" (25 - 305 mm)
Flow Range* 0.1 to 15 fps (0.03 to 4.6 m/s)
Accuracy* ± 2% of Reading
Temperature Range* -32°F to 140°F (0°C to 60°C)
Operating Pressure* 203 psi at 73°F (14 bar at 23°C)
150 psi at 140°F (10 bar at 60°C)

* Ranges vary depending on meter, material, and size

View ULTRASONIC flow meters 

Oval Gear Flow Meters

Oval gear flow meters are a type of Positive Displacement flow meter used to measure the volumetric flow of liquids. These meters directly measure the volume that passes through the meter rather than the velocity or some other physical characteristic of the liquid to calculate the volumetric flow rate, making them a volumetric meter. 

  • Accurate with clean, viscous fluids, unaffected by temperature changes
  • No flow conditioning required, they can be placed directly after pumps or valves with no effect on accuracy
  • Robust
  • High turndown rates
  • Low pressure drop 
  • Excellent for small volume additions
Suits Pipe Sizes 1/8 - 4" (4 - 100 mm)
Flow Range* 0.5 - 2500 L/hr
Accuracy* ± 0.5% - 1% of Reading
Temperature Range* -40°F to 300°F (-40°C to 150°C)
Operating Pressure* 50 psi (3.45 bar) - 1450 psi (100 bar)

 * Ranges vary depending on meter, material, and size

View OVAL GEAR flow meters 

Certifications/Approvals (check product page/datasheet to check which apply to the meter)

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