What is Lubricating Oil ?

Lubricating oil is produced by vacuum distillation of the heavy residue from the primary distillation of crude oil. It is separated into a number of fractions which we can call light, medium and heavy. These fractions are the base oils or feed stocks, for the production of finished lubricating oils. Base oils in certain cases can be used as lubricants without further treatment. If required for special applications they should need further treatment to improve their properties, as may be blended together to give lubricating oils of different viscosities. With the advent of more complicated machinery, the need for specialized and more improved lubrication became apparent, and with the growth of Petroleum Technology, its fulfilment became possible through crude selection, treatment and the use of chemical additives. These additives when added to base oil, either enhance an existing property of the oil or confer additional properties not to be found in the original base oil.


    1. Reducing friction and wear.

    2. Cooling of system.

    3. Cleaning.

    4. Protect the system against corrosion.

    5. Sealing the clearance between moving parts