A lubricant is fundamentally a substance which helps to reduce the friction between two or more surfaces which are in direct contact with each other. The primary purpose of a lubricant is to reduce the friction thereby reducing the amount of heat generated due to friction. A lubricant also helps to reduce the amount of foreign particles or impurities which cause decrease in efficiency of the system containing moving parts. Lubricity is a property which reduces friction with the help of a lubricant. Lubricants are also used for many purposes like the pan in a kitchen to prevent the sticking of foods to the pan, lubricants in our joints made artificially, personal lubrications and much more.
The use of lubricants has known to the world even from thousands of years ago. While in the construction of pyramids, building stones were made to place on the oil soaked lumber. Even animal oil is used as a lubricant from many years ago. The usage of lubrication impacts the industrial revolution drastically which made them use metal-based machinery with a piece of mind.
A good lubricant must possess very high boiling point and very low freezing point. So if we use them in the automobile, it should not freeze when the temperature is low and it should not evaporate when the temperature goes high while running the engine. If the lubricant solidifies or evaporates, the working of automobile shows many errors. It must have high viscosity with hydraulic and thermal stability. It must have very high resistance to oxidation. The important feature that a lubricant must possess is that it must resist corrosion. A good lubricant must protect the system or automobile again wearing whatever may be the pressure and the temperature conditions. The lubricant in the cylinder of an automobile is used not only for heat transfer, debris removal but also for the seal of gasses. It helps to take place a complete combustion, complete exhaustion of gasses in the cylinder.
There are many types of lubricants. They are as follows-
1. Animal oil – Oils extracted from the animals are known as animal oil. Even animal oil is also a type of lubricant. Sperm oil, goose grease comes under animal oil. Sometimes animal oils is also used for food purposes.
2. Vegetable oil – Oils extracted from vegetables and plants are known as vegetable oils. Many people refer to vegetable oils as healthy but they are not really healthy. Animal oils and vegetable oils are not suitable for lubrication in automobiles but not good.
3 Mineral oil – Petroleum, gasoline, diesel, molybdenum sulfide comes under mineral oils. Nowadays, there are many techniques to purify or distil mineral oils and can be condensed without decomposition. So there will be less wastage of mineral oil.
4. Solid lubricants – Molybdenum disulfide comes under solid lubricants. They can be used to directly transmit power in suspensions.
A lubricant can be chosen based on their usage and is mainly classified further into three types. They are
1. Water based lubricant
2. Silicone based lubricant
3. oil based lubricant
The composition is different for different types and will be used according to their work capabilities.
