What is Lubrication: Lubrication is a process or technique when a component is having been made smooth and slippery by the application of Lubricant.
What is Lubricant: A lubricant is a substance which applies between two moving surfaces to reduce friction between them. E.g. Motor oil, Greases, Graphite, Glasses.
Three different types of lubricant and the purpose they serve:
Glasses: Glass is used as a Lubricant for having high viscosity. Usually glass is solid but in high temperature it becomes viscous. Viscosity is a function of temperature but not of pressure which depends on the type of glasses. In addition having poor heat conductivity makes glass useful. Glass works as a thermal bar between hot components. Usually glasses use as lubricant in application of hot extrusion and shaping.
Graphite: Graphite can be used as a lubricant either in its dry or liquid form. It works effectively specially in elevated temperature. Graphite can be applied to a component either by rubbing on it or evaporated to the components surface. Although graphite is a great lubricant but the downside of using graphite is, its needs to be used more often in the moving surface where the friction happen.
Both Glass and graphite is a kind of Solid lubricant. Solid lubricant is widely used rather than oil; even though oil reduces friction due to their fluidity and viscosity while solid lubricants have neither of these properties, but they are still capable of reducing friction and wear. Solid lubricants work in situations where liquid lubricators have no practical value. For instance, solid lubricants may be sprayed on the outer hull of a boat to avoid water contact.
Greases: Greases are solid or semisolid lubricants and generally consist of soaps, mineral oil, and various additives. Greases mostly used in roller bearing and low velocity applications due to high viscosity and sticky property to