Important Parts of a Steam Engine

Important Parts of a Steam Engine Points : Construction of Simple Steam Engine, Important Parts of a Steam Engine, Frame, Cylinder, Steam chest, D-slide valve, Inlet and exhaust parts, Piston, Piton rod, Cross -head, Connecting rod, Crank Shaft, Eccentric, Eccentric rod and valve rod, Fly Wheel, Governor All the parts of a steam engine may be broadly divided in to two group i.e. stationary parts and moving parts. Though a steam engine consists of innumerable parts, both stationary and moving, yet the following are important from the subject point of view:
1. Frame
2. Cylinder
3. Steam chest
4. D-slide valve
5. Inlet and exhaust parts
6. Piston
7. Piton rod
8. Cross -head
9. Connecting rod
10. Crank Shaft
11. Eccentric
12. Eccentric rod and valve rod
13. Fly Wheel
14. Governor 1. Frame It is a heavy cat iron part which supports all the stationary as well as moving parts and holds them in proper position. It, generally, rests on engine foundation. 2. Cylinder It is also a cast iron cylindrical hollow vessel, in which the piston moves to and for under the steam pressure. Both ends of the cylinder are closed and made steam tight. In small s team engine, the cylinder is made an integral part of the frame. 3. Steam chest It is casted as an integral part of the cylinder. It supplies steam 10 the cylinder with the movement of D. slide valve. 4. D-slide valve It moves in the steam chest with simple harmonic motion. Its function is to exhaust steam from the cylinder at proper moment. 5. Inlet and exhaust parts These are holes provided ill' the body of the cylinder for the movement of steam. The steam' is admitted from the steam chest alternately to either side of the cylinder through the inlet parts. The steam, after doing its work in the cylinder, is exhausted through the exhaust part. 6. Piston It is a cylindrical disc moving to and from in the cylinder because of the steam pressure. Its function is to convert heat energy of the steam into mechanical work. Piston rings, made from cast iron, are fitted in the grooves in the piston. Their purpose is to prevent the leakage of team. 7. Piton rod It is a circular rod, which is connected to the piston on one side and cross head to the other. Its main function is to transfer motion from the piston to the cross-head. 8. Cross -head It is a link between the piston rod and connecting rod and connecting is to guide motion of the piston rod and to prevent it from bending, 9. Connecting rod It is made of forged steel, whose one end is connected to the cross head and the other to the crank. Its function is to convert reciprocating motion of the piston (or cross head) into rotary motion of the crank. 10. Crank Shaft: It is the main shaft of the engine having a crank. The crank works on the lever principle and produces rotary motion of the shaft. The crankshaft is supported on main bearings of the engine. 11. Eccentric It is generally made of cost iron, and is fitted to the crankshaft. Its function is to provide reciprocating motion to the slide valve. 12. Eccentric rod and valve rod The eccentric rod is made of forged steel, whose one end is fixed to the eccentric and other to the valve rod. Its function is to convert rotary motion of the crankshaft into to and fro motion of the valve rod. The valve rod connects the eccentric rod and the D-slide valve. Its function is to provide simple harmonic motion to the D-slide valve. 13. Fly Wheel It is a heavy cast iron wheel, mounted on the crankshaft. Its function is to prevent the fluctuation of engine. It also prevents the jerks to the crankshaft. 14. Governor It is a device to keep the engine speed, more or less, uniform at all load condition. It is done either by controlling the quantity or pressure of the steam supplied to the engine,