Piston flow meters are ideal for low viscosity fluids due to the tight tolerances & fits they use.
However, due to these tight fits, clean fluid must be used (or filters put in place) as a particle getting trapped can actually block flow. They operate by a piston moving within a chamber of known volume.
When fluid passes into this chamber, the piston displaces an exact volume of liquid. Piston meters are great for low volume flow measurements.
Piston Flow Meters
Piston Flow Meters offer the highest accuracy and measure the lowest flow rates of any meter. These precision meters are suitable for all low viscosity liquids.
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