There are basically two types of lubricants: petroleum-based and synthetic. Each of these is suited for particular purposes and conditions. The different types are also subject to varying levels of oxidation and degradation, and are compatible with only certain types of machinery components, demands, and environments.
Everyone who owns an automobile knows that the engine oil has to be changed regularly to provide longer engine life. The motor oil in an automobile’s engine is commonly a petroleum-based lubricant. Though it contains the same hydrocarbon base as the gasoline used to power the automobile, the formulations are quite different. The hydrocarbon- or petroleum-based lubricating motor oil is designed to protect the various moving parts of the engine, while gasoline, which is also a petroleum product, is formulated to produce the explosive heat needed to power the engine.
Lubricants may be liquid, such as motor oil and hydraulic oil; they may be semi-solid or solid, such as grease or Teflon® tape, or they may be dry, or powdered, such as dry graphite or molybdenum disulfide. All lubricating materials for mechanized equipment are designed to form some sort of protective coating between moving parts of machinery to protect these parts from undue wear, contamination, and oxidation.
Synthetic lubricants have precisely engineered chemical reactions on particular components. These reactions are created by specifically applying varying amounts of heat and pressure to the components. Synthetic motor oil is gaining popularity for automobile owners who use it in place of petroleum-based motor oil. This type is also used more extensively in industry because, though costlier to use originally, they are better suited to the demands of modern engine and machine technology. Because synthetic motor and machinery oils don’t have to be changed as frequently, consumers actually save in the long run.
There are also petroleum-based and synthetic hydraulic lubricants, also known as hydraulic oils, that are formulated to be lighter and more free-flowing. They are used not only for lubrication, but for the actual operation of hydraulic machinery. Hydraulic oils must be able to flow freely through the pumps that compress the oil for the operation of the machinery, and at the same time, must have the film-forming additives to lubricate the moving parts of the pumping equipment.
Though most modern lubricants are petroleum-based, synthetic bases like vegetable oil, silicones, esters and fluorocarbons are gaining increased popularity for this purpose. The base of a particular lubricating fluid is the primary determinant as to whether it is petroleum-based or synthetic oil.