Application Cautions for Coriolis Mass Flowmeters

If the pressure drop is acceptable, operate a Coriolis mass flowmeter in the upper part of its flow range because operation at low flow rates can degrade accuracy. Note that high viscosity fluids increase the pressure drop across the flowmeter so size of the flowmeter may increase due to accommodate pressure drop constraints, in turn causing flowmeter operation in the lower part of its range and degraded accuracy. Note that even though the flowmeter specification may be (say) 0.1% of rate, the flow measurement accuracy in a particular application could be as high as (say) 2% of rate or worse.

For liquid flows, make sure that the flowmeter is completely full of liquid and contains no gas or bubbles. Conversely, for gas applications, be sure that the flowmeter is completely full of gas and contains no liquid. 

Be especially careful when measuring gas/vapor flow with Coriolis mass flowmeters due to the pressure drops that can occur due to entrance and exit affects. Pay special attention to the piping installation because pipe vibration can cause problems during operation.