LUBRICATION of IC engines and Cooling of IC engines

lubrication of IC engines

1. BY: SHANTANU TRIPATHY SHASHANK DEWANGAN SOUMEN MANDAL SYED HANEEN THALJAI PRATAP DEWANGAN LUBRICATION SYSTEM

2. FUNCTIONS OF LUBRICATING SYSTEM

3. PROPERTIES OF LUBRICATING OIL Viscosity :  A lubricant’s “internal resistance to flow.”  Higher viscosity lubricants are thick and don’t flow, while lower viscosity lubricants have a closer consistency to water and do flow.  The image below demonstrates the viscosity of four different oils.  The ball sinks faster in the thinner, low viscosity oil while it sinks slower in the higher viscosity blends . 2. Viscosity Index:  The rate of change in viscosity with changes in temperature.  In other words, how much viscosity changes as temperature changes.

4. 3. Oxidation Stability:  Oxidation is a reaction that occurs when oxygen is combined with lubricating oil. Variables such as high temperatures, water and acids will accelerate the rate of oxidation. The life of a lubricant is reduced as temperatures increase, leading to varnish and sludge. 4. Pour Point:  The lowest temperature at which a lubricant will flow or pour like a liquid.  This can differ depending on test conditions.  5. Demulsibility :  The ability of a lubricant to separate from water. 6. Flash Point:  The temperature at which a lubricant will ignite when heated and mixed with air, but a flame is not sustained

5. WET SUMP

6. In a typical Wet Sump system, oil is stored in the bottom of the pan and distributed throughout the engine by an internally-mounted pump. An oil pump pickup, mounted to the pump, extends to within a quarter inch of the pan’s bottom to "pickup" the oil. Although a Wet Sump system is essentially the same system used in production cars, it can be enhanced significantly with components that improve oil control and increase power. For performance street and racing applications, these components include high capacity pans, extended oil pump pickups, racing oil pumps, windage trays, oil control kits, racing oil filters and other components. In some racing applications an external oil pump is used, allowing the windage tray or screen to run the pan’s full length.

7. DRY SUMP

8. Unlike a wet sump system where oil is stored in the pan, a Dry Sump Oiling System stores oil in a separate tank — leaving the pan essentially "dry." An externally mounted pump, generally with three or four stages, is used to "scavenge" or remove oil from the pan, deliver it to the storage tank, and send it back through the engine. In a typical setup, all but one of the stages is used to scavenge oil from the pan. A single pressure stage is normally used to return oil from the tank to the engine. The primary advantage of a Dry Sump System is its ability to make more power. With very little oil in the pan, the rotating assembly is not burdened with the weight of excess oil (a phenomenon commonly referred to as " windage ").

9. MIST LUBRICATION SYSTEM

10. Mist lubrication system is a very simple type of lubrication. In this system, the small quantity of lubricating oil (usually 2 to 3%) is mixed with the fuel (preferably gasoline). The oil and fuel mixture is introduced through the carburetor. The gasoline vaporized and oil in the form of mist enters the cylinder via the crank base. The droplets of oil strike the crank base. The droplets of oil strike the crank base, lubricate the main and connecting rod bearings and the rest of the oil lubricates the piston, piston rings and cylinder