What Type Of Flow Meter Is Best For Your Application?
We would love for there to be a one size fits all scenario in instrumentation, however that is not the nature of the science. There are no “universal” flow meters which are suitable for all applications. They are a technical device that is influenced by many different variables. To select the proper technology for an application requires writing a flow specification which covers the use of the meter. There are positives and negatives with each meter type in context of your application, so knowing the critical specifications will be important. The process of choosing the right fit of meter for your needs is about knowing the specifications, to avoid problems down the meter line at a future stage, we recommend not applying guess work.
Some types of flow meters can immediately be eliminated from your selection process as they will not be able to work with your chosen application. For example, electromagnetic flowmeters do not work with hydrocarbons.
There are two basic types of liquid measurement and they are:
So a flow meter is either a volumetric meter or what we call a mass flow meter. Which of these categories best suit your needs depends on the application and also the purpose of your measurement.
Gas – Coriolis Mass, Thermal Mass, Ultrasonic, Variable Area, Variable Differential Pressure, Positive Displacement, Turbine
Liquid – Coriolis Mass, Thermal Mass, Ultrasonic, Variable Differential Pressure, Positive Displacement, Turbine, Electromagnetic
Slurry – Coriolis Mass, some subsets of Variable Differential Pressure, Electromagnetic, Ultrasonic
Vapour – Vortex, Ultrasonic, Diaphragm, Floating Element
Important Questions To Ask
- What Gas or Liquid will be measured?
- Minimum and maximum flow rates.
- What are the accuracy requirements?
- The fluid temperature and viscosity.
- Fluid compatibility with the materials of construction
- The maximum pressure at the location.
- What pressure drop is allowable?
- Straight length requirements?
- Will the meter be mounted in a hazardous location?
- Is the fluid flow continuous or intermittent?
- What type of output signal or readout do you need?