Main components of I.C. Engines

Main components of I.C. Engines Points : Main components of I.C. Engines, Cylinder, Cylinder head, Piston, Piston Ring, Connecting Rod, Crank shaft, Crank Case, Fly wheel As a matter of fact, an IC. Engine consists of hundreds of different parts, which are important for its proper working. The description of all these pails is beyond the scope of this book. However, the main components which are important are described below.
1. Cylinder
2. Cylinder head
3. Piston
4. Piston Ring
5. Connecting Rod
6. Crank shaft
7. Crank Case
8. Fly wheel 1. Cylinder It is one of the most important part of the engine, in which the piton moves to-and-fro in order to develop power. Generally, the engine cylinder has to withstand a high pressure (more than 50 Kg/Cm²) and temperature (more than 2000°C). Thus the materials for an engine cylinder should be suck that it can retain sufficient strength at such a high pressure and temperature. For ordinary engines the cylinder is made of ordinary cat iron. But for heavy duty engines it is made of steel alloys or aluminum alloys, in case of multiple cylinder engines, the cylinders are cast in one block known a cylinder block. Some limes, a liner or sleeve is inserted into the cylinder, which can be replaced when worn out. As the material required for liner is comparatively small, ii can be made of alloy cast iron having long life and sufficient resistance to rapid wear and tear to the fast moving.

2. Cylinder head It is fitted on one end of the cylinder, and acts as a lover to close the cylinder bore. (Generally, the cylinder head contains inlet and exit valves for admitting fresh charge and exhausting the burnt gases. in petrol engines, the cylinder brad also contains a spark plug for igniting the fuel air mixture, towards the end of compression stroke. But in diesel engines, the cylinder head contains nozzle (i.e. fuel valve) for injecting the cylinder. The cylinder head is, usually, cast as one piece and bolted to one end of the cylinder. Generally, the cylinder block and cylinder head are made from the same material. A copper or asbestos gasket is provided between the engine cylinders anti cylinder head to make it airtight joint.

3. Piston It is considered as the heart of an I.C. engine, whose match functions to transmit the force exerted by the burning of charge to the connecting rod. The pistons are generally made of aluminum, .alloys which are light in weight. They have good heat conducting properly and also greater strength at higher temperature.

4. Piston Ring These are circulars rings and made of special steel alloys which retains elastic properties even at high temperatures. The piston rings are housed in the circumferential groves provided on the other surface of piston. Generally, there are two sets of rings mounted on the piston. The function of the upper rings is to provide air tight seal t prevent leakage of (he burnt gases into the lower portion. Similarly, the functions of the lower rings is to provide effective seal to prevent leakage of the oil in to the engine cylinder.

5. Connecting Rod It is a link between the piston and crank shaft, whose main function is to transmit force from the piston to the crankshaft. Moreover, in converts reciprocating motion of the piston into circular motion of the crankshaft, in the working stroke. The upper (i.e. smaller) end of the connecting rod is fitted to the piston and the lower (i.e. bigger) end to crank. The special steel alloys or aluminum alloys are used for the manufacture of connecting rod. Special care is required for the design and manufacture of connecting rod as it is subjected to alternatively compressive and tensile stresses as well are bending stresses.

6. Crank shaft It is considered as the backbone of an I.C. engine whose function is to convert the reciprocating motion of the piston into rotary motion with the help of connecting rod, This shaft contains one or more eccentric portions called cranks. That part of the crank, to which bigger end of the connecting rod is fitted is called crank pin. It has been experienced that too many main bearings create difficulty of correct alignment. Special steel alloys are used for the manufacture of crankshaft. A special care is required for the design and manufacture of crankshaft.

7. Crank Case It is a cast iron, case, which holds the cylinder and crankshaft of an I,C. engine. It also serves as a pump for the lubricating oil. The lower portion of the crank case is known as bed plate, which is fixed with the help of bolts.

8. Fly wheel It is a big wheel, mounted on the crankshaft, whose function is to maintain its speed fairly constant. It is done by storing excess energy during the power strokes, which is returned during other strokes.