Laminar Flow Meters

Laminar Flow Elements, or LFEs, follow the same principle of orifice plates and pitot tubes by creating a pressure drop proportional to flow rate for measuring gas flows, but in an inline flowmeter style. Fluke Mobox/Molbloc Calibrators are designed for calibration of gas flowmeters.

Flow meters measure the flow of fluids and report the results in a volume per time or mass per time such as gallons per minute or Kg/min. Since fluid properties vary so much from corrosive, high temperature, gas, liquid to steam, so do flowmeter technologies and materials. Let’s focus on a few of the technologies carried here at TEquipment.


This Flow Meter section of our website is dedicated to Laminar Flow Elements and Fluke Molbox / Molbloc Calibrators

Laminar Flow Elements (LFE's)

Laminar Flow Elements, or LFEs, follow the same principle of orifice plates and pitot tubes by creating a pressure drop proportional to flow rate for measuring gas flows, but in an inline flowmeter style. They are excellent for measuring low gas flow rates and inherently accurate and repeatable. Better turndowns of 20:1 or better are possible. Flow rate of gas mixtures can also be measured when the percentages of component gases and mixture properties are known.
 
LFEs are applicable in most clean and non-condensing gas flow applications. They excel in critical gas flow measurement applications and make excellent calibration standards because of their inherent accuracy, stable calibration, excellent response time and repeatability. LFEs are used to calibrate turbine meters, variable area meters, flow regulators, mass flow meters, and thermal anemometers to name a few. Gas flow measurement for demanding flow control is a common application.

Molbox/Molbloc Calibrators

Fluke Mobox/Molbloc Calibrators are designed for calibration of gas flowmeters. Molbox/Molbloc, originating with Hart Scientific, and now part of Fluke Calibration, has many proven years in the market and should be considered as a replacement to volumetric bell provers and piston provers for gas flow calibration.

Molbox/Molbloc is ideal for calibration of flowmeters such as

• Thermal Mass Flowmeters
• Variable Area FlowMeters (Rotameters)
• Turbine Meters

Molbox/Molbloc units are much smaller bench instruments that have no moving parts, no need for long straight runs, and provide results directly in mass flow units without needing corrections from volumetric to mass flow. For labs calibrating numbers of thermal mass flowmeters, work can be automated. Contact a TEquipment sales engineer and discuss your application and learn more with these application notes.

Flow Meter/Calibrator Selection Questions

Knowing as much as possible about your application will help in selecting the right technology and specific flow meter or flow calibrator model.

1. Flowing gas data 2. Readout instrument
3. Description of installation configuration
4. Line size
5. Line Material
6. Accuracy required