SEMI - PRESSURE LUBRICATION SYSTEM IN IC ENGINES :

It is also called as partial pressure lubrication system. This is a modification of splash lubrication system. This system is used if the bearing loads are heavy and splash lubrication is not sufficient. It is a combination of splash and pressure lubrication.

This system consists of oil pump, oil gallery , oil filter , oil pressure gauge and scoops attached to connecting rod big end. The pump pumps the oil to the main gallery. From the gallery, oil is forced under pressure to the engine parts to be lubricated. Scoops or dippers are attached to the big end of the connecting rod.

The lubricating oil is directed to the scoops through oil jets from gallery. The scoops splash this oil in all directions to lubricate the engine parts such as piston , cylinder walls etc.

Engine parts lubricated by splash :

'Piston, cylinder walls , cams , piston pin and rings , spring and guides of valve stems , oil pump drive gear

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Mechinopedia For Mechanical Engineers

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