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The greases are obtained by mechanical dispersion of soap in petroleum oil. Soap is obtained when fat alkali used soaps are classified as sodium soap (prepared using NaOH), calcium soap…

Liquid lubricants are classified on basis of original origin as Vegetable oil: these are obtained from plants. E.g. olive oil, palm oil, cottonseed oil etc Animal oil: these are obtained…

The application of solid lubricants are- They are used either in the form of dry powered or mixed with water or oil so that they may stick firmly to the…

The temperature on the moon is 1000C and -1500C during day and night time respectively. Oils and greases cannot withstand such temperature changes but graphite is unaffected within this temperature…

Solid lubricants generally have a laminar structure Structure of graphite Graphite has a layered lattice structure as shown in fig.3.5. The sp2 hybridized carbon atoms are arranged in flat parallel…

A solid lubricant is used in situations such as- Heavy machinery working at very loads and slow speeds. Where parts to be lubricated are not easily accessible. Where a liquid…

The difference between thick film and boundary film lubrication are as follows- Thick film Boundary film lubrication It is also known as film or hydrodynamic lubrication. It is also known…

The classification of the lubricants is they are classified on basis of their physical state as- Solid lubricants E.g.: Teflon, talc, graphite, molybdenum dissuade Semi-solid lubricants E.g.: greases, wax, Vaseline…

Operation conditions: High speed and extremely high temperature High pressure and extreme load When the moving or sliding surfaces are under very high pressure and speed, excessive frictional heat will…

Boundary film or thin film lubrication Operating conditions : This type of lubrication is applied when a continuous fluid-film cannot be maintained and direct metal to metal contact is possible…