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Lubricants


Lubricants:-

                       Those substance which is applied between two moving or sliding surface in order to reduce the frictional resistance called lubricant.

Function of Lubricant:-

       I.            It reduce the frictional forces between two rubbing surfaces.

    II.            It reduces the cost of maintenance of the machines and tools.

 III.            It acts as a cleaning agent to wash off the solid carbon.

 IV.            It acts as a seal and prevents the entry of moisture i.e leakage of gases under high pressure.

    V.            The Lubricant prevents rusting and corrosion.

 VI.            It act as a Coolant.

Lubrication:-

                            The process of reducing frictional resistance between moving surface using lubricants in between them is called Lubrication.

Friction:-

                    Due to mutual rubbing of one part against another, a resistance is developed which tends to retards the motion and produces heat energy, the resistance so developed is termed as friction.

A number of irregularities exist or the surfaces in the form of peaks and valleys called asperities. Peaks and valleys get interlocked and increase the friction. If we fill Lubricant in empty surface of valley then Lubricant make those surface smoother and reduces the friction.

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