INTRODUCTION
A Coriolis mass flow meter is a meter that can be used to measure liquids and gases. It directly measures mass and density and these can be used to calculate actual volume flow in liquids. With gas applications the mass can be converted back to standard conditions with some simple math and a verification of the gas composition. Coriolis meters have been around for over 30 years and as time passes are becoming more accepted in industry where a more precise measurement is needed.
This paper will review Coriolis mass flowmeter technology and applications with reference to measurement of liquids and gases, as well as challenges and best practices.
CORIOLIS FLOWMETER PRINCIPLES OF OPERATION
The Coriolis mass flowmeter is a multivariable device that directly measures the mass of the flowing liquids and gases. The meter also measures the density of liquid and the temperature of the sensor tube. The mass flow and density can be used to calculate the gross volume of liquids.
For gas measurement, the mass flow is divided by the weight of the gas being measured at standard conditions. The low density of gas combined with the accuracy of the Coriolis meters density measurement makes using the density unreliable. The temperature measurement is primarily for correcting for the tensile strength of the tubes but can give a rough approximation of the temperature of the fluid. This temperature is not adequate for custody measurements. Coriolis meters are bi-directional.