Few would dispute the prominent role that flow meters play in plant operations today. Here, we’ll look at how new diagnostics technology and data are enabling Coriolis flow meters to not only address their own performance but also track broader process issues and deliver improvements across plant operations. Central to this is the emergence of new diagnostics and the concept of localized intelligence, through which measurement challenges can be addressed at a local level.
Coriolis Flow Measurement: An Overview
Flow measurement is simply a quantification of the amount of fluid or gas passing through a channel medium, such as a pipe or a duct, with flow typically quantified by the flow meter as a volumetric flow rate (e.g., gal/min) or as a mass flow rate (e.g., lb/hr).
In the case of Coriolis flow meters, in the most common designs, the meter has two parallel flow tubes, and when the process fluid enters the sensor, it is split. During operation, a drive coil stimulates the tubes to oscillate in opposition at the natural resonant frequency. As the tubes oscillate, the voltage generated from each pickoff creates a sine wave – indicating the motion of one tube relative to the other. The time delay between the two sine waves is called delta-T, which is directly proportional to the mass flow rate: the greater the delta-T by the Coriolis force, the greater the mass flow rate.