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Lubrication and Types of Lubrication

In this article, we will discuss the meaning of lubrication, what is a lubricant, the types of lubrication and finally, the functions of lubricants.

Lubrication is the application of a friction-reducing layer between moving surfaces in contact to lessen the friction and tear and wear. A fluid, solid, or plastic material may be utilised as the lubricant. Although this is a correct definition, lubrication does not do nearly as much as described. The lubrication of a surface may be accomplished using various chemicals. The most prevalent are grease and oil. Grease is made from oil or any thickening substitute to achieve consistency, but the oil essentially works and lubricates the machine. Oils might be synthetic, natural, or a mix of the three. Now let us move on to find out what is a lubricant.

Lubricants

If you are wondering what a lubricant is, here’s the answer. Lubricants comprising oil incorporate additives that increase, augment, or reduce the basic oil qualities, depending on how they are applied. The quantity of additives required varies according to the oil and the intended purpose. A dispersant, for example, might be added to motor oil. A lubricant’s principal functions are as follows:

  • Cut down on friction.

  • Reduce wear and tear.

  • Prevent rusting of the equipment.

  • Temperatures may be controlled (dissipate heat).

  • Contamination must be controlled.

  • Power may be transferred by transmission (hydraulics).

  • Make sure there’s no leakage.

Reduce friction and avoid wear might be used interchangeably to answer what is a lubricant and its functions. When it comes to friction and wear, the two terms are used interchangeably yet have different meanings. The differences are considerable. However, not all friction (like fluid friction) leads to wear, and not all wear (like cavitational erosion) causes friction (like cavitational erosion).

Lubrication and lubricants’ primary goal is to reduce friction and several additional advantages. Water and other corrosive chemicals can be protected from the surface by lubricating layers. They also play a key role in keeping systems clean by preventing contaminants from entering them. Using the lubricant, pollutants may be transported to filters and eliminated. They also help regulate temperature by absorbing heat and transferring it to an area with a lower temperature.

Types of Lubrication

Now that we know what is lubricant, let us discuss the types of lubrication. Boundary, mixed, and complete film lubrication are all examples of this. Lubricants and additives in oils serve as wear-prevention mechanisms in each kind.

  • Complete lubrication of film or Full-Film Lubrication

Hydrodynamic lubrication and elastohydrodynamic lubrication are two types of full-film lubrication. Lubrication happens when two surfaces moving against one other are separated by a layer of fluid.

When surfaces are moving in a rolling motion, elastohydrodynamic lubrication occurs in a similar way (relative to each other). The elastohydrodynamic film is thinner than a hydrodynamic film, subject to more pressure. Because the film deforms the rolling surface to lubricate it, it is termed “elastohydrodynamic”.

Irregularities may be found on even the most polished and smooth surfaces. At the microscopic level, they rise and fall, creating peaks and valleys. Peaks like this are known as asperities. The lubricating film must be thicker than the length of the asperities to meet full-film criteria. This method of lubrication and lubricants offers the best surface protection and is, thus, highly sought after.

  • Lubrication of the Boundaries

Boundary lubrication may occur when there are numerous starts and stops, and where stress loading conditions are prevalent, such as in automobiles. EP and AW additives may protect surfaces in the event that complete film thickness cannot be obtained because of speed, load, or other causes.

To protect the metal from wear, these chemicals adhere to the surface and create a layer that is sacrificed in the process. In a boundary lubrication situation, just the EP or AW layer serves as a barrier between the two surfaces. This is not ideal because of the high friction, heat, and other unwanted consequences.

  • Mixed Lubrication

When it comes to lubrication, mixed lubrication is a hybrid of boundary and hydrodynamic. A lubricating layer separates the majority of the surfaces, yet the asperities still come into touch. And here we return to the additives.

It will be simpler to define the functions of lubricants after you have a better knowledge of this process. It is a method of reducing friction, heat, wear, and energy consumption by either separating or shielding surfaces. These fluids might include oils, greases, gases, and more. The next time you do routine maintenance on your automobile, such as changing the oil or lubricating a bearing, remember that there is more going on than meets the eye.

Conclusion

Lubrication is essential to the performance and lifespan of any spinning machinery. Preventing early bearing failures and increasing machine uptime, productivity, and energy efficiency are all possible with the right lubrication system. Using lubricant helps solid items move in close proximity. It might be a solid, a liquid, or any other plastic material that is available. In order to keep the machine working smoothly and safely, the functions of lubricant are to produce a layer between the metal surfaces of the machine components. The primary goal of lubrication is to minimise friction. Boundary lubrication, mixed lubrication, and complete film lubrication are all forms of lubrication.

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Get answers to the most common queries related to the NEET UG Examination Preparation.

Using two different lubricants in the same engine is possible?

Ans. Although it is not suggested, some guidelines must be followed if various oils must be blended. To get the most...Read full

How does using a lubricant affect fuel efficiency?

Ans. Since you already know what lubricant is, it is time to understand its significant functions. To ensure that modern lubricants effectively red...Read full

What is the mechanism through which lubricants function?

Ans. Lubricants are designed to reduce friction when moving components as well as the active resistance of stationar...Read full

What is it that is used to lubricate?

Ans. Base oils (most typically petroleum fractions, also known as mineral oils) constitute 90 per cent of lubricants...Read full

What is the manufacturing process for lubricants?

Ans. Lubricating oil is derived from crude oil and refined further. After passing through a purification process kno...Read full