Presentation On: TRIBOLOGY

BY, VISHAL PRAKASH SAMUNDRE

T.Y. MECHANICAL ROLL NO: 56

GUIDED BY, MR. S C HISWANKAR

MAHARASHTRA INSTITUTE OF TECHNOLOGY, AURANGABAD

WHAT IS TRIBOLOGY?

Derived From the Greek word ‘tribos’ means rubbing or sliding.

It focuses on friction, wear and lubrication of interacting surfaces in relative motion.

It is applied to an operational analysis to problems of great economic significance.

English equivalent name is friction and wear or lubrication science.

NEED OF TRIBOLOGICAL STUDY

To minimize and eliminate losses.

Greater efficiency, performance, fewer breakdowns & savings.

Study various losses and analysis of losses.

Reduce losses by introducing a layer of lubrication.

Atomic and molecular observations on sliding surfaces.

VARIOUS TERM IN TRIBOLOGY

Wear & Various types of wear

Friction

Lubrication & Various types of lubrication

WEAR

Abrasion, erosion, Cavitation are forms of wear.

Loss of material by the passage of hard particles over a surface known as Abrasive Wear.

Erosive wear is caused by the impact of particles against a solid surface.

Cavitation wear is caused by the localized impact of fluid against a surface or fast flowing fluids.

EROSIVE WEAR

CAVITATION WEAR

Cyclic formation and collapse of bubbles on a solid surface. Bubble formation is caused by the release of dissolved gas from the liquid, which has negative pressure.

FRICTION

Force that resists the sliding or rolling.

Needed for the satisfactory functioning of nuts and bolts, paper clips, and tongs, etc.

Experimental facts characterize the friction of sliding solids:

The amount of friction is nearly independent of the area of contact.

Friction is proportional to the load or weight that presses the surfaces together.

LUBRICATION

Thin layers of gas, liquid and solid interposed between two surface.

Layers of material separate contacting solid bodies.

The thicknesses of these films range from 1 - 100 [pal].

Main aim of lubrication is to reduce the wear and friction.

TYPES OF LUBRICATIONS

Hydrodynamic lubrication- Analysis of Gaseous or liquid films is usually termed

Solid lubrication- Lubrication by solids is termed, Ex. Graphite

Elastohydrodynamic lubrication- Physical interaction between the contacting Bodies and the liquid lubricant.Hydrostatic lubrication- Complete separation of sliding surfaces with negligible wear and very low friction. Applied to aerostatic and hybrid bearings.

TRIBOLOGICAL INSTRUMENTS

TRIBOMETER

Measures tribological quantities, such as coefficient of friction, friction force, and wear volume.

Invented By- Dutch scientist Musschenbroek.

TRIBOMETER

WORKING OF TRIBOMETER

ADVANTAGES

Helps in reducing friction and wear.

Proper type of lubrication can be easily selected

Increased efficiency and life of a product or machine.

Best utilization of a machine can be achieved.

CONCLUSION

The study of Tribology is important so as to increase the efficiency of any machine components or parts which has relative motion between them due to which friction and wear occurs in the machine or component. A tribological study has helped in various sectors like polymers, metals and gases.