LUBRICATION SYSTEM IN IC ENGINES AND PURPOSES :

In an IC Engine, moving parts rub against each other causing frictional force. Due to the frictional force, heat is generated and the engine parts wear easily. Power is also lost due to friction. To reduce the power loss and also wear and tear of the moving parts, a foreign substance called lubricant is introduced in between rubbing surfaces. The lubricant keeps the mating surfaces apart. Lubricant may be solid (graphite) , or semi-solid (grease) or liquids (oil) . The liquid lubricant is generally used is mineral oil. This is obtained by refining petroleum. Grease is also used to lubricate certain parts of the engine.

PURPOSES OF LUBRICATION (OR) FUNCTIONS OF LUBRICATION :

a) It reduces friction between moving parts.

b) It reduces wear and tear of the moving parts.

c) It minimizes power loss due to the friction.

d) It provides cooling effect - During Circulation, It carries that from the hot moving parts and delivers it to the surrounding through crankcase.

e) It provides cushion effect - It serves as a cushion against the shocks of the engine.

f) It provides cleaning action - Impurities such as carbon particles are dissolved during its circulation.

g) It provides a scaling action - It helps the piston rings to provide an effective seal against high pressure gases in the cylinder from leaking out.

h) It reduces Noise.

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ELECTRICAL COMPARATORS AND ITS WORKING

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Mechinopedia For Mechanical Engineers

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