HOW TO CALIBRATE A FLOW METER

HOW TO CALIBRATE A FLOW METER

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Flow Meter Calibration

1. How to Calibrate a Flowmeter ?

A flowmeter is a device that is used to measure the rate of flow of gaseous or liquid substances and then indicate the flow reading to the instrument using an analogue or digital output. It provides crucial measurement data to industry types, from maritime to Oil & Gas. The flow rate is defined as the average velocity at which a gas or fluid moves through the pipe or closed tubular channel. To ensure the flow meter indicates a precise and accurate reading, it must be calibrated on a right time intervals.

2. What is Flow Meter Calibration?

Calibration is that the process of checking an instrument to see it's accurate. Flowmeter calibration is that the same process where the measurement is flow. Calibration of a flowmeter is often achieved in one among several ways, but generally involves the comparison of the flowmeter against a reference standard of upper accuracy. Calibration is an important a part of an instrumentation system to make sure a line of traceability of the measurement system is maintained.

To know the flowmeter performance over a period of your time, flowmeter calibration should be conducted on “Timely” basis so meter drift analysis is often assessed. With further customer agreement, an extra adjustment of the flow meter reading maybe performed to minimise the flowmeter errors.

3. Flowmeter Calibration Procedures In these discussions, we'll describe the varied flowmeter methods and procedures related to liquid flowmeters. Liquid flow meter calibration are often wiped out several ways, but always involves the comparison against a typical, this maybe a primary or secondary reference standard, depending upon the accuracy required. The three principles for fluid flowmeter calibration use Gravimetric, Volume or Transfer standard calibration methods. i. Gravimetric Calibration Gravimetric calibration is one among the foremost accurate methods for flowmeter calibration both for volumetric and mass based flow calibration and is classed as a primary standard calibration.

The gravimetric method is right for liquid flowmeter calibrations on oil and water based flowmeters where they will be sent to an external calibration laboratory. The flowmeter calibration procedure involves the diversion of the fluid onto a mass comparator over a given timescale, where the essential mass flow measurement springs by mass over time calculation. This is often an easy process often mentioned because the bucket and stopwatch method. Albeit this is often an easy procedural method, to realize measurement accuracies suitable for the calibration for top accuracy and transfer standard reference meters a big effort is required to know and minimise the measurement uncertainty contributors. To achieve a volume based flow measurement the fluid density must be measured. ii. Piston Prover Calibration Piston prover flow meter calibration also can achieve high accuracy results accurate results and is out there to a wider customer base thanks to the better portability of the piston provers. The quantity flow springs from the quantity of fluid displaced by the piston multiplied by the piston travel length over the measured period of time.

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Flow Meter Calibration

iii. Transfer Standard Master Meter Calibration A transfer standard calibration uses a reference grade or master flowmeter and compares the reference flow against the flowmeter under test whist operating at equivalent conditions. It’s important to know any differences within the operating conditions because of the location of another meter within the test line and any changes to temperature or pressure within the fluid. Reference meters should even be of highest quality and performance and have an in depth history of performance.

Master flowmeters are almost often calibrated to an accredited ISO 17025 standard.

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Flow Meter Calibration