Title Exp 1 Study of IC Engines components.pdf.pdf ✅

1 Experiment No. 1 Aim To study the various components of Internal Combustion Engine. Internal Combustion Engine (IC Engine) IC engines are those heat engines that burn their fuel inside the engine cylinder. Most of the engine used in motor vehicle is Reciprocating internal combustion engine. Since the burning of fuel taking place inside the closed chamber and the resulting heat energy converted to mechanical energy (reciprocating motion) it is named so. Construction Features and Functions of Engine Parts Following are the main components of Automotive Engine 1) Cylinder head It is a single piece casting, covered at top of the cylinder block. It consists of passages for oil and water circulation, accommodates valves, spark plugs/ injectors and heater plugs. Gasket is used between the cylinder head and cylinder block to avoid leakage. 2) Cylinder Block The cylinder block is usually made up of cast iron or aluminum, it consists of cylinder, and passages for the coolant and lubricating oil. It forms a part of foundation and main stationary body of the automobile
2 engine. In modern engine the cylinder block and crankcase form a single casting which gives rigid structure. 3) Crankcase The bottom of cylinder block is covered by crankcase. It acts as the base of the engine. It supports the crankshaft and camshaft with suitable bearings and provides arms for supporting the engine on the frame. The lower part of cylinder block and oil pan together called as crankcase. Usually, Cylinder block and upper half of the crankcase are cast as a single integral unit. Normally the casting is made up of ferrous alloy or semi-steel. 4) Oil Pan or Sump The bottom portion of crankcase is called the oil pan or sump. It is bolted to the lower flange of the main casting and made of pressed steel or aluminum. It serves as a reservoir for the storage, cooling and ventilation of engine lubricating oil. The oil in sump is recirculating between the pan and the working parts of the engine. 5) Piston It is cylindrical in shape reciprocates inside the cylinder, its functions are to compress the air /fuel mixture inside the combustion chamber, transmit the power developed during combustion to the crankshaft through the connecting rod without loss of gas from above or oil from below. 6) Piston Ring A piston ring is a metallic split ring that is attached to the outer diameter of a piston. The main functions of piston rings in 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. 7) Connecting Rod It is the connection between piston and the crankshaft. Its main function is to convert the reciprocating motion to rotary motion. It has small end and big end. Small end of the connecting rod is connected to the piston pin and big end to the crank pin. Connecting rod has I-beam cross section and is made of forged steel. It carries the power thrust from piston to the crank pin and hence it must be very strong, rigid and also as light as possible so as to have greater power and less vibration because reciprocating weight is less.
3 8) Crankshaft It transmits the torque to the flywheel by converting the reciprocating motion of the piston into rotary motion. It consists of crank pin, crank arm and balancing weights. The front end of shaft carries drives for cam shaft, vibration damper to control torsional vibration and the fan belt pulley. At the rear end flywheel is fitted. 9) Fly wheel It is a heavy steel wheel attached to the rear end of the crankshaft. The size varies depends on the number of the cylinder. The purpose of the fly wheel in engine is to keep the engine speed constant. It is also used as a part of clutch mechanism. Flywheel has teeth on its outer edge to mesh with starter motor for cranking. 10) Valves Inlet valve admits fuel and air to cylinder and burned gases escapes through exhaust valve. Also it acts as seal for combustion chamber while both valves are closed.
4 11) Camshaft It is a shaft on which cams are mounted. It is mounted either at cylinder block or in the cylinder head. The Cam shaft changes the rotary motion of the camshaft into linear motion of follower or lifter. Cam shaft function is to open and closing of valves.