Flow Meter Calibration
What flow meter to calibrate or not?
What flow meter to calibrate or not dependent on the specific configuration of the process and how much influence a given measurement will have on such process performance.
Usually, routine calibration of flow meter part of secondary loop systems is redundant as any drift in the measurement will be corrected by the action of a primary loop or an operator that makes set point adjustment based on some other process measurement. This is also true for flow meter parts of any loop that acts as an intermediate means to a given process end. These loops are usually measured by some other provision and they are unlikely to require absolute flow measurement accuracy, it usually be sufficient that flow meter offer only stable, consistent performance in the short term.
On other hand, flow meters that are likely to require routine calibration include those relating to product quality and quantity, feedstock quality and quantity, energy/fuel quantity and critical process operating point.