Basic construction of a diesel engine

The power of a diesel engine originates in the cylinder. Oil fuel is sprayed into the cylinder by the fuel-injection pump. There it meets the air which was compressed by the piston while the piston was being pushed upward in the cylinder. The oil burns producing heat and more pressure. The hot confined gases press the piston downward with greater force than was used to push it upward. The piston pushes on the connecting rod which connects the piston to the crank on the crankshaft. The force on the crank makes the crankshaft turn in its bearings, and the rotating crankshaft supplies power to the machinery the engine drives. This is the way in which the diesel engine changes the heat energy of oil into mechanical power. These operations are performed by the following essential parts: 1. A piston sliding in a cylinder. The piston has two jobs: first, to compress the air change, second, to receive the pressure of the gases while they are burning and expanding. Each piston is fitted with piston rings. Generally rings above the piston pin seal the combustion chamber, and those below the piston pin, the oil rings, control the amount of oil on the cylinder walls. Piston rings also assist in the transfer of heat from the piston to the cylinder walls. 2.A cylinder head which closes the top end of the cylinder so as to make a confined space in which to compress the air and to confine the gases while they are burning and expanding. 3.Valves or ports to admit the air and to discharge the spent or exhaust gases. 4. A connecting rod to transmit force in either directions from the piston to the crank on the crankshaft. 5. A crankshaft and the main bearings which support the crankshaft and permit it to rotate. 6. A supporting structure to hold the cylinders, crankshaft and main bearings in firm relation to each other. This structure is usually made up of two parts, called frame and bedplate. 7. A fuel-injection pump to force the oil into the cylinder, also fuel-injection nozzle to break up the oil into a fine spray as it enters the cylinder. 8. A camshaft, driven by the crankshaft, to operate the fuel-injection pump and also to open valves. 9. A flywheel to store up surplus energy on the power (firing) stroke and to return that energy when the piston is being pushed upward on the compression stroke. 10. A governor or a throttle to regulate the amount of fuel supplied at each stroke, and thus control the engine speed and power. 11. Miscellaneous parts, such as piping to supply air and remove exhaust gases, lubricating system to lubricate the moving parts, water jacket to cool the cylinder. 12. A blower-in a two-stroke cycle engine.

Answer these questions:

a)

1. Каковы особенности создания механической энергии в дизельном двигателе?

2. Как называется основные части дизельного двигателя?

b)

1. Where does the power of a diesel engine originate?

2. What is the process of power originating in the cylinder of a diesel engine?

3. What are the essential parts of a diesel engine?

Read Text 4 and translate it into Russian. Make up your own Vocabulary. Try to memorize the main terms.

Text 4