Difference between cSt and mm²/s for base oil viscosity

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sid_raptor
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hi all
can someone explain me the units of Base oil viscosity of grease?
for example is there a difference between grease rated at 200cSt and 200 mm2/s
if so then what is the meaning of cSt and what does it stand for?

thanks
 

Discussion

They are the same units for kinematic viscosity. The unit of viscosity in the centimeter-gram-second system was called the Stokes (after the physicist who first studied it, discovered Stokes' Law, etc).

1 Stokes = 1 cm2/sec
1 centistoke = 1/100 Stokes = 1 mm2/sec

The SI unit for kinematic viscosity doesn't have any special name.

FWIW the kinematic viscosity of water at about 20C is 1 mm^2/sec, which may explain why values are usually given in mm^2/sec not m^2/sec (which is the basic SI unit).
 
so cSt is centistokes then? lol why did i not think of that!
thanks for your help mate! much appreciated!