Technical Information; Fluid Viscosity - WEBTEC CTR Manuel Utilisateur

Technical information

All flow meters are calibrated at 21 cSt as standard. Special calibration is available over a custom flow range or at a
different viscosity, please contact sales to discuss your application.

Fluid viscosity

The performance of a turbine flow meter can be affected by the viscosity of the fluid measured. Our turbine flow meters
are calibrated at between 18 and 26 cSt as standard (a mean viscosity of 21 cSt), which is the typical kinematic viscosity
for a hydraulic fluid operating at 50 °C. The kinematic viscosity of all hydraulic fluids is related to the fluid temperature and
the table below shows the affect of temperature on the kinematic viscosity of a range of typical grades of hydraulic oil.
The shaded area of the table shows the range of viscosities that can be measured by a flow meter with standard
calibration with minimal effect on the accuracy (less that ± 1% FS).
Flow meters can be specially calibrated at a different viscosity to the standard or we can advise on the expected error
when the flow meter is used at other viscosities, please contact sales for further information.
10
Pressure Drop Chart
Hydraulic Oil Viscosity 21 Centistokes (fully open load valve)
10.0
5.0
1.0
0.5
5 10
CT/LT600R,CT750R,CT/LT800R
CT/LT300R,CT/LT400R
50 100 500
Flow (lpm)
Note
1 UK gallon = 4.546 litres
1 US gallon = 3.785 litres
1000