Английский язык. Арланова Т.Л - 4 стр.

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4
Diesels or Electrics?
The diesel and electric locomotives have some common features. As well
as the electrics (electric locomotives), the diesels(diesel locomotives) are
always ready for service because the diesel engine can be started within a
minute or two in any weather and can be in operation for perhaps a week
without visiting a depot. As well as the electrics, the diesels are capable of
developing a high tractive effort at low speeds and, therefore,can start and
accelerate heavy trains. These features allow the diesel locos to be used for
heavy mainline service.
On the other hand, the diesel locomotive is more expensive to build and
maintain than the electric of equal power since the diesel locomotive carries a
power plant on itself. In addition, the diesel engine is an air pollutant prime
mover, so the diesel traction should not be recommended for use on
suburban lines round large cities. Noise and vibration are also considered the
drawbacks of the diesel locomotive. Another disadvantage of the diesel
locomotive is that the diesel engine runs on organic fuel the supplies of which
are not inexhaustible. Diesel traction is normally employed today on non-
electrified trunk lines and on lines where traffic is not dense enough to justify
electrification.
The history of railway traction is abundant in types of energy used for
starting trains. In the second half of the 20
th
century aerospace engineers
designed turbotrains the operation of which was based on the technology of
flight. The new American turbotrain had an aircraft-type gas-turbine engine
and developed a speed of 157 miles/h on standard jointed rail tracks. In
France turbotrains began running between Paris and Cherbourg in 1971.
Each power car of the train carrying a pair of gas turbines contained a
driver’s cab which had been specially designed to give the maximum driving
efficiency and control. On Paris-Lyon route gas-turbine locomotives
developed a maximum speed of 300 km/h. British Advanced Passenger Train
(APT) consisted of two aerodynamically-styled power cars each fitted with
four 300-h.p.
Exercise 4. a) Make a list of advantages of diesel locomotives. Use the text
to help you:
1 can start heavy trains
2 _________________
3 _________________
4 _________________
b) Make a list of disadvantages of diesel locomotives. Use the text to help
you:

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