Friction is a force that resists one surface from sliding or rolling over another. Therefore, it can be said that friction only occurs when two surfaces are in relative motion the techniques for reducing friction are:
Surface Finish — The number, roughness and even the directional contact points of the asperities on the surfaces can dramatically affect the frictional coefficient. Temperature — Both ambient and operational temperature can affect friction. For example, temperature is a critical element in whether an anti-wear or extreme pressure additive will be effective in certain applications. Operational Load — Friction varies directly with load. A load exceeding the designed capacity will dramatically increase the frictional coefficient. Relative Speed — Increasing the speed beyond that which is safely specified will dramatically increase friction. Nature of the Relative Motion between the Surfaces — Sliding motion versus rolling motion can affect the coefficient of friction. Lubricant Characteristics — These characteristics are the base oil, the viscosity of the base oil and the additives combined with the base oil for the particular formulation.

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Use of ball-bearing or roller bearing
Use of correct combination of surfaces in contact
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