How to Calibrate a Flow Meter & Calibration Procedures

- Aug 27, 2019-

What is Flow Meter Calibration?

Flow meter calibration is the process of comparing the pre-set scale or metering of a flow meter to a standard scale of measurement and adjusting its metering to conform to the standard. Calibration is an essential aspect of instrumentation in a broad range of industries that require high-accuracy measurements with a negligible percentage of error e.g. in Oil & Gas, Petrochemical, and manufacturing.

Flow meters are calibrated by comparing and adjusting their metering to correspond with a predefined standard. Flow meter manufacturers typically calibrate their products in-house after production or send them to an independent calibration facility for adjustment.

Flow Meter Calibration vs. Recalibration

Flow meter calibration involves comparing the measurements of a flow meter in operation to that of a standard flow measurement device under the same conditions and adjusting the scale of the flow meter to be in close agreement with the standard.

Flow meter recalibration involves calibration of a flow meter which is already in use. Periodic recalibration is essential as flow meter readings will often go ‘out of phase’ over time due to variable conditions involved in industrial processes.

The main difference between the two procedures is that flow calibration is done before the meter is sent out for use while recalibration is done after the flow meter has been in operation for a while. Software tools can also be used to verify the accuracy of measurements after a flow meter has been calibrated.

How to Calibrate a Flow Meter

Liquid flow meter calibration can be done in several ways, but always involves comparison and adjustment of the flow meter under test to conform to a standard. In the U.S., calibration obtained from the National Institute of Standards and Technology (NIST) is the standard, while for most of Europe, the calibration standard originates from the Van Swinden Laboratory in the Netherlands.