Constituents Of Engine Oils
Functions of Engine Oil
The functions of engine oil are as follows-
Grades Of Engine Oil
Society of Automotive Engineers (SAE) has developed numerical coding system to grade the engine oils according to their viscosity. SAE viscosity index includes the following numbers: 0, 5, 10, 15, 20, 25, 30, 40, 50 and 60. Lower numbers means lower viscosity and a higher number means a higher viscosity.
Monograde Engine Oil
Multi Grade Engine Oil
Why Do We Need Multi Grade Oils?
The engine oil has to encounter different temperature conditions as the engine operates. When the vehicle is parked or during winters, its temperature falls to a very low level. During running condition the engine produces huge amount of heat. This heat is carried away by the engine oil, increasing its temperature. At low temperatures the engine oil remains thick and viscous. When heated it becomes thinner.
During winters or generally at the time of starting, the oil remain cool. At low temperature the viscosity of the oil decreases making it highly viscous. The highly viscous oil do not flow easily. It is also very difficult to pump it, all along the engine. It puts huge load on pump and may also cause oil filters to choked. At the time of starting, the engine oil need to be pumped quickly to all the components. This is not possible with highly viscous oil. Hence, at low temperatures the engine oil need to maintain a lower viscosity.
At higher temperatures the viscosity of the oil decreases and it becomes thinner. If the the viscosity drops below the optimum levels, the chances are high that thin oil layer can not prevent metal to metal contact. This may increase the rate of wear and tear of engine components. So, at higher temperatures the engine oil must have sufficient viscosity to form a thick lubricating layer around the components.
To cater to these requirements we need an engine oil which neither become too viscous at low temperatures nor becomes too thin at high temperatures. This problem is solved by multi grade engine oils. These oils contain different additives which helps them in maintaining optimum viscosity at all operating temperatures. These additives are polymeric compounds called viscosity modifiers.
Naming of engine oil
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5W30 oil |
These were some basic information regarding engine oil. Looking at the importance of engine oil we must always use the quality oil specified by the automobile companies. Always use the recommended grade of engine oil so as to improve the performance of your vehicle.All engines require some form of lubrication and this is provided by the engine oil. This oil is required to carry out numerous different tasks when the engine is in operation, the primary function is to lubricate all the components by reducing friction and preventing or reducing metal to metal contact. The oil stops two surfaces from touching each other by forming a thin lubricating layer on mating