Crude petroleum, as it comes out of an oil well, cannot be used for industrial or automotive applications. First, it must be subjected to special treatments in specific plant, refineries, where a large variety of products are obtained.

From among these products, those used in making lubricants are what are called base oils, which can be of the following types:

Mineral oils: Obtained directly from petroleum. These are the most common.

Synthetic: Manufactured from bases which come from complex transformations or synthesis.

Semisynthetic: A mixture of the two.

So a lubricant oil is a product consisting of a base oil, generally derived from petroleum, and some additives (compounds added to the base oils, normally in small quantities, to give a finished lubricating oil with the desired quality for the type of application wanted).

The most important additives, in terms of their functions, are:

• Anti-oxidants.
• Anti-rust agents.
• Detergents.
• Dispersants.
• Viscosity index improvers.
• Anti-wear agents.
• Pour point depressants.

The most important physical and chemical characteristics of finished lubricants are:

• Colour.
• Viscosity.
• Viscosity index.
• Density.
• Flash point.
• Combustion point.
• Pour Point ºC
• Extreme pressure.
• Aeroemulsion.
• Deemulsification.
• TBN.

The quality and performance of lubricants is determined by the quality of the bases used, the improvements given by additives used and the physical and chemical characteristics of the finished lubricant.

For more information, consult our Glossary and FAQ sections.

In terms of the types of application, the most important oils are:

• Oils for 2 and 4-stroke engines
• Oils for transmissions and gear boxes.
• Industrial purpose oils.
• Marine oils.
• Lubricating greases (bearings).

Lubricants reduce friction between two surfaces in contact and moving relative to each other, as well as carrying out other vital funcitons for the operation of machinery:

Sealing, Refrigerating, Protecting, Cleaning.