Tribology :Tribology Science and engineering of interactive surface in relative motion. Presented by: Mukut ch. Medhi Somnath Dey Dhiru Kamal Deka Md Shaifuddin Dept. of Mechanical Engineering Tezpur University


Tribology :Tribology Tribology (origin in 1960’s) Tribology= tribos+logos Rub Principle or logic


Brown’s first law of applied Tribology :Brown’s first law of applied Tribology IF IT'S RUNNING IT'S WEARING !!! IF IT'S NOT RUNNING IT'S PROBABLY WORN!


Tribology :Tribology Two bodies in relative motion . Results Friction Static friction Frictional heat, resistance against movement (friction force), loss of energy. Wear Material loss degradation of surface, decreasing functionality.


Examples of Tribology :Examples of Tribology Industrial Tribology Machine parts/engines Lubrication Oil Grease Friction and wear Decreasing performance


Wear Definition :Wear Definition Most wear is an combination of several mechanisms


Wear Mechanisms :Wear Mechanisms Adhesive Low contact pressures Augmented asperities Abrasive High contact pressures Wear tracks


Friction :Friction Origin of friction Deforming of the surface : deformation energy Adhesion of two bodies: non-linear adhesion hysteresis Atomic adhesion model Van Der Waals Capillary forces Electron interactions Dynamic friction –static friction


Lubrication :Lubrication Lubrication is the process, or technique employed to reduce wear of one or both surfaces in close proximity, and moving relative to each another, by interposing a substance called lubricant.


Types of lubricants :Types of lubricants Liquid lubricants Lubrication with oil Cooling and removal of debris Protection against metal-metal contact Hydrodynamic lubrication Lowering friction=lowering energy input into the surface. Lubrication with grease Oil in wax Low cooling effect/no hydrodynamic lubrication Alternative when oil lubrication is impossible


Types of lubricants :Types of lubricants Solid lubricants and self-lubricating materials Plastics, PTFE, MoS2, , Graphite


Important properties of lubricants :Important properties of lubricants Wide range of viscosity Little change in viscosity with temperature Chemical stability Sufficient specific heat to carry away frictional heat Low cost Easily available


Bearings :Bearings It is mechanical element that permits relative motion between two parts such as shaft and housing. Ball Bearing


Classification :Classification Depending on type of friction Sliding contact bearing Rolling contact bearing Depending on type of force Radial Thrust


Rolling and sliding contact bearing :Rolling and sliding contact bearing Rolling contact bearing and sliding contact bearing


Radial and thrust bearing :Radial and thrust bearing


Rolling contact bearing :Rolling contact bearing Deep groove ball bearing Cylindrical roller bearing Angular contact bearing Self aligning bearing Taper roller bearing Thrust roller bearing


Rolling bearing :Rolling bearing


Different types of bearings :Propeller bearing Water lubricated polymer bearing Water lubricated bearing Different types of bearings


Application :Application Industrial Process Tribology in biological science Tribology in engines


Industrial process :Industrial process Rolling-Sheet metal Wire drawing Tube expansion Deep drawing


Rolling-Sheet metal :Rolling-Sheet metal


Rolling-Sheet metal :Rolling-Sheet metal


Wire drawing :Wire drawing


Tube expansion :Tube expansion


Deep drawing :Deep drawing


Tribology in biological science :Tribology in biological science


Tribology in engines :Tribology in engines Lubrication of engine


Lubrication of engine :Lubrication of engine Valve train Sump1 Sump2 Piston assembly Crank shaft


Degradation of lubricant :Degradation of lubricant Piston Assembly Sump Sump Piston


Piston Assembly :Piston Assembly


Extraction of Oil from Top Piston Ring :Extraction of Oil from Top Piston Ring


Solutions to tribological problem :Solutions to tribological problem Trial and error method Material selection Parameter selection Lubricant Simulation method Selection of simulation Material selection Parameter selection Field data


Conclusions :Conclusions Tribology is a multi-disciplinary science that is based onto experience and common sense. Boiler feed pumps: 49% of the failures causing outages were because of tribological components. Friction, wear and failure of tribological components are costing industry billions of dollars


Reference :Reference www.falexint.com www.wikipedia.org lqme.sjtu.edu.cn www.TRIBOLOGY-ABC.com Design of machine elements- V.B BHANDARI Fundamentals of Tribology-Basu, Sengupta, Ahuja


Thank You :Thank You Question’s ?....