Zahn cup

A Zahn cup is a viscosity measurement device used in the paint industry.

On paint standard specifications, one denotes viscosity in this manner: efflux time, Zahn cup number.

One can convert efflux time to kinematic viscosity by using an equation for each cup specification number, where t is the efflux time and ν is the kinematic viscosity in centistokes.

Note the above equations are for a Brookfield series of Zahn cups.

[1] Ascott Zahn Cups are based on measuring the Flow of liquid in seconds.