Special text: Unusual railways Special text: Underground railways
Yüklə 471,05 Kb.
|
| NOTE
1. the stage-coaches—почтовые кареты (дилижансы) 2. flanged wheels —колеса с гребнем (круговым выступом, удерживающим колесо на рельсе) 3. sides ar.d ends—боковые и торцевые стенки вагона 4. the box car — крытый грузовой вагон 5. the gondola car—полувагон 6. the hopper car—вагон-хоппер (с разгрузочными люками в полу) 7. a double-deck car—двухъярусный вагон 8. four-wheel trucks —двухосные тележки вагона ESSENTIAL VOCABULARY
LESSON 10. THEME: IN SEARCH OF HIGHER SPEEDS I (1) The advance of transportation took a long time and scores of talented engineers did all in their power to develop the transportation system people have now at their disposal. But man never stops at what he has reached, and what seems fantastic today turns out to be quite realizable tomorrow. (2) Speed has always been a highly desirable goal for the engineers in their attempts to perfect the existing means of rail transport. This problem is of particular significance when it comes to developing a passenger transportation system. Railway history knows many examples when test runs of modified or newly designed trains resulted in speed records. They prove that the possibilities of high speeds have not yet been exhausted. (3) Were it possible to design a train running at the speeds of the aircraft, railways could successfully compete with aviation. At the same time, it is desirable that the new train should run over the existing tracks without requiring costly reconstruction or frequent renewals of the permanent way. (4) In this respect, the Soviet-made ER-200 train now operating on a commercial basis is worfii mentioning. This train meets the requirements of high speeds, safety and passenger comfort. A lot of preparatory work had to be done on the Oktyabrskaya Railway before the ER-200 was put into service. Running on some sections at 200 kph, the train covers a distance of 650 km between Moscow and Leningrad in 4 hours 39 minutes thus cutting the journey time by 4 hours compared with the previous schedules. (5) Many latest achievements of railway technology have been incorporated in the new Soviet express train. The stream-lined shape of the whole train cuts down air friction and allows higher speeds to be attained. The driving compartment being equipped with cab signalling, the driver has, at all times, signals displayed before him. The job of the locomotive driver has been greatly facilitated. Pushing a controller1 is all he must do to start or brake down the train. (6) The coaches the ER-200 is composed of are extremely comfortable, being supplied with air-conditioning, sound-proof windows and soft aircraft-like seats. The passengers who happen to travel by the new Soviet express have snack-bars at their disposal. Their journey is accompanied by background music. (7) Another high-speed train of interest is the British Advanced Passenger Train (APT). The remarkable feature of this 200 kph train is its ability to go round curves safely at speeds 40 per cent faster than those now acceptable for conventional trains and do it without causing discomfort to passengers. This ability was due to a special suspension of the train body. Another key feature of the APT was its ability to stop from 200 kph within a considerably shorter distance than that allowed for 160 kph trains. Besides, lightweight alloys were to help it travel faster and save a considerable amount of energy needed for its propulsion. However, numerous technical innovations incorporated in its design involved so many problems and risk that the British Railways authorities found it cheaper to take this train out of service, II (8) One more proposition for new nigh-speed ground, transport is contactless systems which show great promise fast regards speeds. These systems may be divided into two principal types: the air-cushion system and the magnetic suspension system. Both, of, them have one feature in common: 2 there is a thin film of air between the vehicle and the track which can be provided either by turbo-jet engines or by powerful magnets. (9) Serious investigations in these systems are being carried on in France, Britain, Japan, the USSR, the USA and Canada. But it is France that has succeeded in creating the world's first practical version of a train riding on an air cushion. The train being now operated commercially has already reached 186 mph. Successful as it is,3 the air-cushion train is unlikely to be 'acceptable in densely-populated areas because of noise and air pollution. (10) It is magnetically-suspended vehicles that seem to be more advantageous. These vehicles are suspended above the track by electromagnetic attraction or repulsion and propelled by electric motors of special design. There being no metal friction, very little power would be required for propulsion. Being silent in operation, the magnetically-suspended vehicles would be suitable forsuburban and city areas. Besides, they are pollution-free and thus have not undesirable effects on the environment. (11) It should be mentioned, however, that one of the main obstacles on the way to introducing contactless transport is that it needs a specially designed concrete track. (12) In this respect, the so-called Corridor system recently designed in the USA is more advantageous for high- speed intercity passenger service. The system is intended' for carrying several thousands of passengers in an hour between Boston and Washington and is based on a few simple calculations: (1) The maximum speed along the Corridor must be something about 400 mph. To attain this speed the train should be protected from ice and from the objects which might fall on its path. That's why the train should travel in a tube. (2) To eliminate air friction, most of the air should be pumped out of the tube. For heavy continuous traffic a pair of tubes would, be needed. (3) The air at atmospheric pressure should be admitted behind the train to accelerate it; a similar effect could-decelerate the train to a stop. (4) Each train would .he half a mile long and would run on conventional steel wheels. (13) Although very costly, the Corridor system is likely to offer a number of economic benefits in addition to numerous conveniences to travellers. Yüklə 471,05 Kb. Dostları ilə paylaş:
|