Viscosity index is a change in viscosity with temperature: Viscosity decreases rapidly with increasing temperature
- Ex: Parafinique mineral oil, viscosity decreased 7 times when increasing T from 60 to 120 degrees C.
- The decrease in viscosity as the temperature increases depends on the chemical structure of the oil.
|VISCOUS TYPE||VISCOSITY INDEX (VI)||APPLICATION RANGE|
|High quality synthetic oil||300||Used for aviation and space industry|
|Synthetic oil||200||Used for high-end engines, high-end hydraulics, gearboxes, bearing large loads and friction in formula races.|
|Paraffin mineral oil with improved additives VI||140||Used for high-end engines, high-end hydraulic.|
|Paraffin mineral oil||100||Used for motors, hydraulics, common gears.|
|Napthen oil||50||Used for air conditioning, transformers, technology oil …|
|Aromatic oil||0||Used to plasticize rubber|