various parts of an i.c. engine pdf
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The document describes various components of an internal combustion engine, including the cylinder, piston, crankshaft, and valves, detailing their functions and materials used in their construction. It emphasizes the importance of each part in facilitating the engine's operation and performance. Key components like the fuel injector, spark plug, and carburetor are also highlighted for their roles in fuel management and ignition.
various parts of an i.c. engine pdf
- 1. 23/01/2017 P.I.T. Submitted by: Submitted to: SUJIT KUMAR ABHISHEK SHARMA 1508131119 (LECTURER OF MECHANICAL MECH. IV (B) DEPARTMENT) 2ND GROUP
- 2. 23/01/2017 P.I.T. Experiment no. 1 Date: - 23/01/2017 Objective: - To study the different component of Internal Combustion Engine. Apparatus Required: - Model of Internal Combustion Engine
- 3. 23/01/2017 P.I.T. Theory: - COMPONENTS OF INTERNAL COMBUSTION ENGINE Engine Cylinder:- Cylinder is the main body of IC engine. Cylinder is a part in which the intake of fuel, compression of fuel and burning of fuel take place. The main function of cylinder is to guide the piston. It is in direct contact with the products of combustion so it must be cooled. For cooling of cylinder a water jacket (for liquid cooling used in most of cars) or fin (for air cooling used in most of bikes) are situated at the outer side of cylinder. At the upper end of cylinder, cylinder head and at the bottom end crank case is bolted. The upper side of cylinder is consists of a combustion chamber where fuel burns. To handle all this pressure(50 kg/ ) and temperature(more than 2000℃) generated by
- 4. 23/01/2017 P.I.T. combustion of fuel, cylinder material should have high compressive strength. So it is made by high grade cast iron. It is made by casting and usually cast in one piece. Cylinder Head: - The top end of cylinder is closed by means of removable cylinder head. There are two holes or ports at the cylinder head, one for intake of fuel and other for exhaust. Both the intake and exhaust ports are closed by the two valves known as inlet and exhaust valve. The inlet valve, exhaust valve, spark plug, injector etc. are bolted on the cylinder head. The main function of cylinder head is to seal the cylinder block and not to permit entry and exit of gases on cover head valve engine. Cylinder head is usually made by cast iron or aluminum. It is made by casting or forging and usually in one piece.
- 5. 23/01/2017 P.I.T. Piston: - Piston is considered as the heart of an I.C. Engine. It is fitted to each cylinder as a face to receive gas pressure and transmit the thrust to the connecting rod. It is the prime mover in the engine. The main function of piston is to give tight seal to the cylinder through bore and slide freely inside of cylinder. Piston should be light and sufficient strong to handle the gas pressure generated by combustion of fuel. So the piston is made by aluminum alloy and sometimes it is made by cast iron because light alloy piston expands more than cast iron so they need more clearances to the bore. Piston Rings: - A piston must be a fairly loose fit in the cylinder so it can move freely inside the cylinder. If the piston is too tight fit, it would expand as it got hot and might stick tight in the cylinder and if it is too loose it would leaks the vapor pressure. To provide a good sealing fit and less friction resistance between the piston and cylinder, pistons are equipped with piston rings. These rings are fitted in grooves which have been cut in the piston. They are split at one end so they can expand or slipped over the end of piston. A small two stroke engine has two piston rings to provide good sealing but in a four stroke engine has an extra ring which is known as oil ring. Piston rings are made of cast iron of fine grain and high elastic material which is not affected by the working heat. Sometimes it is made by alloy spring steel.
- 6. 23/01/2017 P.I.T. Connecting Rod: - Connecting rod connects the piston to crankshaft and transmits the motion and thrust of piston to crankshaft. It converts the reciprocating motion of the piston into rotary motion of crankshaft. There are two end of connecting rod one is known as big end and other as small end. Big end is connected to the crankshaft and the small end is connected to the piston by use of piston pin. The connecting rods are made of nickel, chrome, and chrome vanadium steels. For small engines the material may be aluminum.
- 7. 23/01/2017 P.I.T. Crank Shaft: - The crankshaft of an internal combustion engine receives the efforts or thrust supplied by piston to the connecting rod and converts the reciprocating motion of piston into rotary motion of crankshaft. The crankshaft mounts in bearing so it can rotate freely. The shape and size of crankshaft depends on the number and arrangement of cylinders. It is usually made by steel forging, but some makers use special types of cast-iron such as spheroidal graphitic or nickel alloy castings which are cheaper to produce and have good service life. Cam Shaft: - Camshaft is used in IC engine to control the opening and closing of valves at proper timing. For proper engine output inlet valve should open at the end of exhaust stroke and closed at the end of intake stroke. So to regulate its timing, a cam is use which is oval in shape and it exerts a pressure on the valve to open and release to close. It is driven by the timing belt which drives by crankshaft. It is placed at the top or at the bottom of cylinder. It takes driving force from crankshaft through gear train or chain and operates the inlet valve as well as exhaust valve with the help of cam followers, push rods and rocker arms.
- 8. 23/01/2017 P.I.T. Gudgeon Pin: - These are hardened steel parallel spindles fitted through the piston bosses and the small end bushes or eyes to allow the connecting rods to swivel. It connects the piston to connecting rod. It is made hollow for lightness. It is made of steel. Crank Case: - The main body of the engine to which the cylinder are attached and which contains the crankshaft and crankshaft bearing is called crankcase. It serves as the lubricating system too and sometime it is called oil sump. All the oil for lubrication is placed in it.
- 9. 23/01/2017 P.I.T. Fly wheel: - Fly wheel is a rotating mass used as an energy storing device. A flywheel is secured on the crankshaft. The main function of flywheel is to rotate the shaft during preparatory stroke. It also makes crankshaft rotation more uniform. It is done by storing excess energy during the power strokes, which is returned during other strokes.
- 10. 23/01/2017 P.I.T. Intake & Exhaust valves: - To control the inlet and exhaust of internal combustion engine, valves are used. The number of valves in an engine depends on the number of cylinders. Two valves are used for each cylinder one for inlet of air-fuel mixture inside the cylinder and other for exhaust of combustion gases. The valves are fitted in the port at the cylinder head by use of strong spring. This spring keep them closed. Both valves usually open inwards. Governor: - As the name indicates, it controls the speed of engine by controlling the fuel supply. It controls the speed of engine at a different load by regulating fuel supply in diesel engines. In petrol engines, supplying the mixture of air-petrol and controlling the speed at different load conditions.
- 11. 23/01/2017 P.I.T. Spark plug: - It is used in petrol engine only. The main function of a spark plug is to ignite the compressed air fuel mixture. It is fitted on cylinder head. The spark plug consists of a metal shell having two electrodes which are insulated from each other with an air gap. Carburetor: - It is a small but the important part of engine. It converts petrol in fine spray and mixes with air in proper ratio as per requirement of engine. The working life and performance of engine is mostly dependent on the carburetor.
- 12. 23/01/2017 P.I.T. Fuel Injector: - Injector is usually used in compression ignition engine. It sprays the fuel into combustion chamber at the end of compression stroke. It is fitted on cylinder head. Fuel injection is a system for mixing fuel with air in an internal combustion engine. It has become the primary fuel delivery system, which is used in automotive petrol engines. The primary difference between carburetors and fuel injection is that fuel injection atomizes the fuel by forcibly pumping it through a small nozzle under high pressure, while a carburetor relies on low pressure created by intake air rushing through it to add the fuel to the airstream. The fuel injector is only a nozzle and a valve: the power to inject the fuel comes from a pump or a pressure container farther back in the fuel supply. Fuel Pump: - It is an important part of fuel supply system, which supplies petrol to the carburetor by sucking from the fuel tank.
- 13. 23/01/2017 P.I.T. Manifold: - The main function of manifold is to supply the air fuel mixture and collects the exhaust gases equally form all cylinder. In an internal combustion engine two manifold are used, one for intake and other for exhaust. They are usually made by aluminum alloy. Pushrod: - Pushrod is used when the camshaft is situated at the bottom end of cylinder. It carries the camshaft motion to the valves which are situated at the cylinder head.
- 14. 23/01/2017 P.I.T. Engine bearing: - Everywhere there is rotary action in the engine, bearings need. Bearings are used to support the moving parts. The crankshaft is supported by bearing. The connecting rod big end is attached to the crank pin on the crank of the crankshaft by a bearing. A piston pin at the rod small end is used to attach the rod to the piston, also rides in bearings. The main function of bearings is to reduce friction between these moving parts. In an IC engine sliding and rolling types of bearing used. The sliding type bearing which are sometime called bush is use to attach the connecting rod to the piston and crankshaft. They are split in order to permit their assembly into the engine. The rolling and ball bearing is used to support crankshaft so it can rotate freely. The typical bearing half is made of steel or bronze back to which a lining of relatively soft bearing material is applied.