Flow Measurement · Glossary

What is K Factor?

Symbol: Kpulses per litre, m³ or gallonFlow Measurement

K factor is the number of pulses a flow meter sends for each unit volume of fluid passing through it.

K Factor Explained

Turbine, vortex, positive displacement and many other pulse output meters have a K factor printed on the tag or calibration certificate. The receiving counter divides pulses by K to get volume.

K is found by calibration and may vary slightly with flow rate and viscosity. A meter factor from proving corrects it in service.

K Factor Formula

Q = f ÷ K and Volume = N ÷ K

f	pulse frequency (Hz)
N	counted pulses
K	pulses per unit volume

Example: K = 50 pulses/L at 250 Hz gives 5 L/s, which is 18 m³/h.

Calculators for K Factor

CalculatorK Factor CalculatorFree online calculator with formula and worked example.CalculatorMeter Factor CalculatorFree online calculator with formula and worked example.CalculatorFlow Totalizer CalculatorFree online calculator with formula and worked example.

Free Downloads

Free downloadFlow Measurement Formulas Cheat SheetFree printable PDF cheat sheet.

Frequently Asked Questions

What is K Factor?

K factor is the number of pulses a flow meter sends for each unit volume of fluid passing through it.

Is K factor the same as meter factor?

No. K factor converts pulses to volume. Meter factor is a correction found by proving that adjusts the indicated volume.

Does a pitot tube have a K factor?

Averaging pitot tubes use a flow coefficient also called K, but it is a different quantity from a pulse K factor.

Learn more on the blog

Types of flow meters

A practical guide on instrumentationblog.in with more detail on K factor and how it is applied on real plants.

Read Full Article

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