Presentation On TRIBOLOGY BY VISHAL PRAKASH SAMUNDRE T

Presentation On: TRIBOLOGY BY, VISHAL PRAKASH SAMUNDRE T. Y. MECHANICAL ROLL NO: 56 GUIDED BY, MR. S C HISWANKAR

WHAT IS TRIBOLOGY? Ø Derived From the Greek word ‘tribos’ means rubbing or sliding. ØEnglish equivalent name is friction and wear or lubrication science. ØIt focuses on friction, wear and lubrication of interacting surfaces in relative motion. ØIt is applied to an operational analysis to problems of great economic significance.

NEED OF TRIBOLOGICAL STUDY Ø To minimize and eliminate losses. Ø Greater efficiency, performance, fewer breakdowns & savings. Ø Study various losses and analysis of losses. Ø Reduce losses by introducing a layer of lubrication. Ø Atomic and molecular observations on sliding surfaces.

VARIOUS TERM IN TRIBOLOGY Ø Wear & Various types of wear ØFriction ØLubrication & Various types of lubrication

WEAR Ø Abrasion, erosion, Cavitation are forms of wear. Ø Loss of material by the passage of hard particles over a surface known as Abrasive Wear. Ø Erosive wear is caused by the impact of particles against a solid surface. ØCavitation 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 ØForce that resists the sliding or rolling. ØNeeded for the satisfactory functioning of nuts and bolts, paper clips, and tongs, etc. Experimental facts characterize the friction of sliding solids: Ø The amount of friction is nearly independent of the area of contact. Ø Friction is proportional to the load or weight that presses the surfaces together.

LUBRICATION ØThin layers of gas, liquid and solid interposed between two surface. ØLayers of material separate contacting solid bodies. ØThe thicknesses of these films range from 1 - 100 [pal]. ØMain aim of lubrication is to reduce the wear and friction.

TYPES OF LUBRICATIONS ØHydrodynamic lubrication- Analysis of Gaseous or liquid films is usually termed ØSolid lubrication- Lubrication by solids is termed, Ex. Graphite ØElastohydrodynamic lubrication- Physical interaction between the contacting Bodies and the liquid lubricant. ØHydrostatic lubrication- Complete separation of sliding surfaces with negligible wear and very low friction. Applied to aerostatic and hybrid bearings.

TRIBOLOGICAL INSTRUMENTS TRIBOMETER ØMeasures tribological quantities, such as coefficient of friction, friction force, and wear volume. ØInvented By- Dutch scientist Musschenbroek.

TRIBOMETER

WORKING OF TRIBOMETER

ADVANTAGES ØHelps in reducing friction and wear. ØProper type of lubrication can be easily selected ØIncreased efficiency and life of a product or machine. ØBest 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.