The document provides a detailed description of various internal combustion engine components, including the cylinder block, piston, connecting rod, crankshaft, camshaft, and flywheel, along with their functions and materials used. It explains the importance of each part in engine operation, efficiency, and design specifications, such as piston clearance and piston ring functions. Additionally, it emphasizes the role of a flywheel in energy storage and controlling speed variations in the engine cycle.

1. I C Engine components

2. Cylinder Block:
• It is the main block of the engine.
• It contains cylinders accurately finished to
accommodate pistons
• The cylinder block houses crank, camshaft, piston
and other engine parts.
• In water cooled engines, the cylinder block is
provided with water jackets for the circulating
cooling water.
• The materials used for cylinder are grey cast iron,
aluminium alloys etc.,
• It is usually made of a single casting

3. Cylinder block of
motorcycle
Cylinder block of
Car

4. • Cylinder Head:
• The cylinder head is bolted to the cylinder
block by means of studs.
• The water jackets are provided for cooling
water circulation.
• The materials used for cylinder head are cast
iron, aluminium alloy etc.
• This is also generally made of single cast iron.

5. PISTON OF IC ENGINES

6. PISTONS

7. • Piston is one of the most important part in a reciprocating
engine in which it helps to convert the chemical energy
obtained by combustion of fuel into useful mechanical power.
• Piston is essentially a cylindrical plug that moves up and down
in the cylinder.
• It is equipped with piston rings to provide a good seal
between the cylinder wall and piston.
• The efficiency and economy of the engine primarily depends
on the working of piston.
• It must operate in the cylinder with minimum friction and
should be able to withstand a high explosive force developed
in the cylinder and also the very high temperature ranging
from 2000 to over 2800 during operation.
℃ ℃
• Some of the materials used for piston are cast iron,
aluminum alloy, chrome nickel alloy, nickel iron alloy
and cast steel.

8. • The piston should be as strong as possible, however its weight
should be minimized as far as possible in order to reduce the
inertia due to its reciprocating mass.
• The top of the piston is called head.
• Ring grooves are cut on the circumference of the upper
portion of the piston.
• The parts below the ring grooves is called skirt.
• The portion of the piston that separates the grooves are called
the lands.
• Some pistons have a groove in the top land called a heat dam
which reduces heat transfer to the rings.
• The piston bosses are the reinforced sections of the piston
designed to hold the piston pin or wrist pin.

10. -
Piston Clearance:
• Pistons are usually small in diameter than the bore of the cylinder.
• The space between the piston and the cylinder wall is called the piston
clearance. This clearance is essentially for the following reasons:
1) It provides a space for a film of lubricant between the piston and
cylinder wall to reduce friction.
2) It prevents piston seizure due to very high operating temperature, piston
and cylinder block expand the cylinder is cooled better than the piston,
hence sufficient clearance should be provided for the piston to expand,
fail in which the piston seizure will result.
3) If there is no clearance between the piston and cylinder, it will be
impossible for the piston to reciprocate in the cylinder.
4) The amount of piston clearance depends upon the size of the cylinder
bore and the metal used in the piston. It is generally 0.025 mm to 0.100
mm

11. PISTON WITH HORIZONTAL SLOT

13. PISTON RINGS
 A piston ring is a split ring that fits into a groove on the outer diameter
of a piston in a reciprocating engine such as an internal combustion
engine or steam engine.
The main functions of piston rings in reciprocating engines are:
1) Sealing the combustion chamber so that there is minimal loss of gases
to the crank case.
2) Improving heat transfer from the piston to the cylinder wall.
3) Maintaining the proper quantity of the oil between the piston and the
cylinder wall
4) Regulating engine oil consumption by scraping oil from the cylinder
walls back to the sump.
 Most piston rings are made of a very hard and somewhat brittle cast
iron.

14. Cylinder Liners
Piston Rings

15. PISTON RINGS

16. OIL RING

19. OIL RINGS

20. The piston head is often flat but may be shaped to suit the
combustion chamber. The combustion space can be controlled
by dishing or doming the piston crown and recess for the valve
heads can also be machined into the crown. The compression
ratio can be more accurately controlled by machining the
combustion chamber in the piston, but it means that most of the
heat of combustion has to be dissipated through the piston in
stead of the cylinder head.

21. Connecting Rod:
• It connects the piston and crank shaft.
• It transmits the force of explosion during power
stroke to the crankshaft.
• The connecting rod has bearings at both ends.
• The small end of the connecting has a solid or split
eye and contains a bush.
• This end is connected to the piston by means of a
gudgeon pin.
• The other end is called as big end of the connecting
rod.
• The connecting rods must withstand heavy thrusts.
• Hence it must have strength and rigidity.
• They are usually drop forged I sections.
• The materials used are plain carbon steel, aluminium
alloys, nickel alloy steels etc,

23. Crank Shaft :
• It is the main rotating shaft of the engine.
• Power is obtained from the crank shaft.
• The crank shaft is combination with connecting rod
converts reciprocating motion of the piston into rotary
motion.
• The crank shaft is held in position by the main bearings.
• There are two main bearings to support the crank shaft.
• The materials used for crank shaft are billet steel, carbon steel,
nickel chrome and other heat treated alloy steels.

24. Camshaft:
• Camshaft contains number of cams.
• It is used to convert rotary motion into linear or straight line
motion.
• It has so many cams as the number of valves in an engine.
• An additional cam is also provided to drive the fuel pump.
• A gear is provided in the cam shaft to drive the distributor or
oil pump.
• The opening and closing of the engine valves are controlled by
the cams provided on the cam shaft.

25. Flywheel

26. • A rotating mechanical device that is used to store rotational
energy.
• A flywheel is used in machines , serves as a reservoir which
stores energy during the period where the supply of energy is
more than the requirement.
• Conversely, a flywheel releases stored energy by applying
torque to a mechanical load, thereby decreasing the flywheel’s
rotational speed.
• In other words it can be defined as “it stores energy during
power stroke and delivers during idle strokes”.
• A little considerations will show that when the flywheel
absorbs energy, its speed increases and when it releases, the
speed decreases. Hence a flywheel does not maintain a
constant speed, it simply reduces the fluctuation of speed.
• The flywheel’s position is between the engine and clutch patch
to the starter.

27. Function of Flywheel
1. Flywheel absorbs energy, its speed increases and
when it releases energy, the speed decreases.
2. Hence a flywheel does not maintain a constant speed,
it simply reduces the fluctuation of speed.
3. In other words, a flywheel controls the speed
variations caused by the fluctuation of the engine
turning moment during each cycle of operation.

28. Application of Flywheel
1. Flywheel is used to maintain constant angular
velocity of the crankshaft in reciprocating Engine.
2. Flywheel is used to provide continuous energy in
systems where the energy source not continuous.
3. A flywheel is used to supply intermittent pulses of
energy at transfer rate that exceed the ability of its
energy source.
4. Flywheel is used in riveting machine to store energy
from the motor.
5. Flywheel is used to orient satellite instrument without
the use of thruster rocket.