Lubrication can be a daunting obstacle to someone unfamiliar with its basic concepts. Even someone with experience can be confused by the technology of current machinery combined with the multitude of lubricants available on the market today. Reviewing a few of the basic principles of lubrication can make it easier to see why proper lubrication is necessary in every application.

Webster defines friction as the “rubbing of one body against another,” and as “resistance to relative motion between two bodies in contact.” Friction can be beneficial. As we overcome this resistance to motion between two objects in contact, heat is generated. This heat is what warms our hands or starts a fire. Friction is also the principle behind the braking systems we find on our automobiles. In fact, once we were able to get a car moving, there would be nothing to stop it without friction except the effects of gravity or other objects.

However, friction can also be our enemy when heat generated as the result of friction causes damage. With the contact of two moving parts friction and wear occur in these areas of contact. Thus, it leads to material failures, overheating and the formation of wear deposits.

Although there are many ways to reduce friction, the most common way is through the use of a fluid or semi-fluid material. The key characteristic of such materials is that they are not readily compressible. Fluid and semi-fluid materials allow us to minimize component contact or eliminate contact altogether such fluids are commonly referred to as lubricants.

There are three types of lubrication or lubrication situations that can exist between two surfaces separated by a lubricant. Whether or not these situations occur is dependent upon the ability of the lubricant to provide adequate protection to the moving surfaces. When a fluid lubricant is present between two rolling and/or sliding surfaces, a thicker pressurized film can be generated by the movement of the surfaces (at their respective velocities). The non-compressible nature of this film separates the surfaces and prevents any metal-to-metal contact.

Though the ability to minimize friction is the number one function of a lubricant, there are other major functions that must be considered.

Lubricants are generally composed of two groups of materials. The first is a base or stock fluid a fluid that makes up 75 to 95 percent of the finished product. The most commonly used stocks today are derived from petroleum crude oil. These stocks are also referred to as mineral or synthetic oils.

As time goes on; the lubrication needs of equipment continue to change. As equipment becomes more sophisticated the demands placed upon the required lubricants become more severe. What may have been a preferred lubricant in the past is likely to be totally unacceptable today. The automotive industry is an excellent example of how demands on equipment have changed. The engines used in today’s cars require significantly more from motor oil than they did only a few years ago. For improved fuel economy, most cars are now using lighter oils, yet the same cars have engines that produce more power per cubic inch of displacement than ever before.

To achieve this power level, designers add turbo chargers that further expose the oils to higher temperatures and greater stress. Requirements for cleaner exhaust emissions contributed to higher levels of contaminants in the oil and also increased the oil’s operating temperature. By reducing the aerodynamic drag of new vehicles, designers inadvertently minimized the amount of air that flows over hot engines and drive trains that cause operating temperatures to increase still further. Even with all of these changes, designers are still requiring lubricants to last longer than they ever did before, so the demand for synthetic lubricants continues to increase.

Although the engineering of each synthetic lubricant varies depending on the particular base stock, synthetics are generally made through a reaction process. This reaction process significantly improves the consistency of the stock and its molecular uniformity. Mineral stocks, on the other hand, are obtained through a process of distillation. Distillation slightly limits the molecular diversity that may exist within the stock but, does not completely eliminate nonessential molecular structures. This is important because unnecessary molecular structures produce variations in the stock’s performance.

The ideal lubricant’s chemical composition is one in which the molecular construction is identical throughout, such as in a synthetic base stock. Because of the way synthetic stocks are produced, they are molecularly uniform and contain significantly fewer undesirable materials than a mineral base stock. Molecular uniformity also affects the properties that each type of lubricant possesses. The properties of mineral oils tend to vary due to inconsistencies in the crude from which they are obtained. The properties and performance features of synthetics, on the other hand, are very predictable. Once again, this is due to their molecular uniformity. AMSOIL synthetic lubricants are formulated to take advantage of the superior properties of synthetic base stocks. They provide excellent lubrication and wear protection and have been designed to resist the chemical breakdown processes that limit the service life of conventional mineral-based oils.