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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ELECTRICAL COMPARATORS AND ITS WORKING

Electrical Comparators are used as a means of detecting and amplifying small movements of a work contacting elements. An electrical comparator consists essentially of a pick-up head or transducer for converting a displacement into a corresponding change in current and a meter or recorder connected in the circuit to indicate the electrical change, calibrated to show in terms of displacement. Generally, an amplifier is needed to provide the requisite sensitivity and to match the characteristics of different parts of the circuit. Electrical comparators can be classified according to the electrical principle used in the pick-up head. Most of the comparators use either a differential transformer, an inductance bridge, a strain gauge or a capacitor as a means of detecting movement of the gauging element. There are different types of electrical comparators. One kind called an electrolimit gauge is used to check or measure the outside diameter of a roll. The object to be checked is place

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Advantages And Disadvantages Of Air Refrigeration System :

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Mechinopedia For Mechanical Engineers

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