Answer: The NOACK Volatility Test (ASTM D5800) determines evaporation tendencies of a lubricant (engine oil) in high temperature service. The more an engine oil vaporizes (or evaporates), the heavier the oil becomes. Heavier, more viscous oil circulates poorly, which affects fuel economy, oil consumption and emissions.
Similarly, what does Noack mean?
Yes NOACK is an extreme test for oil evaporation. To meet API SN standards no more than 15% may evaporate in the given time. Oil with a high NOACK will thicken faster in use.
Furthermore, what is the volatility of lubricating oil?
For example, engine oil volatility is a measure of the resistance of an oil to evaporation under high- temperature operating conditions. This is important for an engine lubricant because the loss of lower molecular weight components can significantly impact the viscosity.
What is oil viscosity index?
The viscosity index (VI) is an arbitrary, unit-less measure of a fluids change in viscosity relative to temperature change. It is mostly used to characterize the viscosity-temperature behavior of lubricating oils. The lower the VI, the more the viscosity is affected by changes in temperature.