Presented by:- ARAVIND P V MS S5 NO:-60 LUBRICATION SYSTEM Presented by:- ARAVIND P V MS S5 NO:-60

FUNCTIONS OF LUBRICATION Lubrication is a art of admitting a lubricant between two surfaces that are in contact and in relative motion. FUNCTIONS OF LUBRICATION To reduce friction and wear between the moving parts and thereby the energy loss. To provide a sealing action against high pressure gases in the cylinder. To cool the surfaces by carrying away the heat generated in engine components. To clean the surface by washing away carbon and metal particles caused by wear.

Different types of lubrication systems MIST LUBRICATION -> WET SUMP LUBRICATION SPLASH -> PRESSURE FEED -> DRY SUMP LUBRICATION ->

MIST LUBRICATION This system is used where crankcase lubrication is not possible It is not using nowadays mainly used in 2 stroke engine. In this the lubricating oil is mixed with fuel, the usual ratio is 3-6% The fuel oil mixture is vaporized goes via crankcase into cylinder. The mixture strikes the moving or mating parts and hence lubrication held's. Less in cost and simplicity are main advantages. Heavy exhaust smoke due to burning of lubricating oil. During closed throttle process as in the case of vehicle moving down the hill, the engine will suffer from insufficient lubrication as the supply of fuel is less. This is an important limitation of this system. <-

WET SUMP LUBRICATION SYSTEM SPLASH Mainly used in light duty engines The oil is drawn by a pump and delivered through a distributing pipe. The oil is thrown by a small projection called DIPPER at the big end of connecting rod. The oil is kept in crankcase and a certain level is maintained . The oil is forced through drilled holes and passages. The dipper provided at the big end drops in the oil and is splashed into the piston and other parts of engine which needs lubrication. Oil pockets are provided to catch the splashing oil, and from the pockets the oil will flow to the bearing surfaces through a drilled hole.

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PRESSURE FEED In which the oil is drawn in from the sump and forced to all the main bearings of the crankshaft through distributing channels. An oil hole is drilled in the crankshaft from the centre of each crankpin to the centre of an adjacent main journal, through which oil can pass from the main bearings to the crank pin bearing. Next the hole connects piston pin, and to connecting rod. Main components * Strainer * Pressure regulator * Filter * Breather A pressure relief valve is provided which automatically keeps the delivery pressure constant and can be set to an value.

Rotor type gear pump is using in this. Most of the oil from the pump goes directly to the engine bearings and remaining flows through cartridge filter which filters solid particles in oil. This helps to reduce contamination of dust and carbon particles. <-

DRY SUMP LUBRICATION The supply of oil is carried in an external tank. An oil pump draws oil from the supply tank and circulates it under pressure to the various bearings of the engine. In this the capacity of scavenging pump is always greater than oil pump. A filter with a bypass valve which always fits place between scavenge pump and the supply tank. A separate oil cooler with either water or air as the cooling medium, is usually provided in the dry sump system to remove heat from the oil.

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PROPERTIES OF GOOD LUBRICANTS Oiliness to ensure adherence to the bearings. Should not react with the lubricating surfaces. A low pour point to allow flow to allow flow of the lubricant at low temperatures to the oil pump. No tendency to form deposits by reacting with air water fuel or the products of combustion. Cleaning ability Non toxic and non inflammable Low cost Availability