2020-06-30
551
“ Thermal electrical plants.”
Hydroelectric stations deliver power from great rivers, but still about 80 per cent of the required electric power is produced in thermal electrical plants. These plants burn coal, gas, peat or shale to make steam.To understand how the energy of fuel is converted into electrical energy let us discuss the heat process and begin with the fuel.
Gas is delivered through gas pipelines. The coal (peat, shale) arrives in trains, and conveyors or cranes unload it for storage and bring it to the furnace. It is more effective to burn coal in the form of powder, therefore it is first crushed, pulverized and blown into furnaces. To attain complete combustion of the powder a large volume of air is needed, delivered by forced air fans, exhauster fans and smoke stacks. The steam boilers or steam generators supply the huge amount of high-pressure, high-temperature steam required to drive the high-power turbine-generators.
The kinetic energy of its steam acts against the blades of the turbine and rotates its shaft joined to the generators shaft.A centralized control desk with panels and many instruments and automatic control devices supervises and monitors the plant, with only a few operators.
Вопросы к тексту:
- Where are hydroelectric stations located?
- What does the kinetic energy of the steam do with the blades of the turbine?
- What does a centralized control desk to?
- Why are there only a few operators at such electrical plants?
Задание № 2. Переведите следующие слова и словосочетания:
to require, to convert, fuel, to deliver through pipelines, to supply, the generator shaft, a centralized control desk,to drive the high-power turbine generators, to monitor, to feed, fans, combustion, power input, raw materials, voltage transformer, high-pressure.
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Вариант №8
Задание№1. Переведите текст и письменно ответьте на вопросы к нему.
“ Freight cars”
Nearly all of us known more about passenger train cars and passenger trains that we know about freight train cars and freight trains, since we have all ridden on passenger trains while a great many of us have never had anything to do with shipping goods on freight cars. The cars on a freight train are known to be seldom alike, they are usually of many types and sizes, special kinds of freight requiring special kinds of cars. But nowadays one can see the so-called bulk trains, that is, trains consisting of wagons of one type only for regular transporting large quantities of goods from one place to another. All world railways have several classes of commonly used cars and there are usually several kinds of cars in each class.
One of the most widely used cars is the cars is the car for transporting coal from mines. This car is called an open-top car, for it has no roof. There are two types of open-top cars, the hopper and gondola car, the latter having a flat floor or bottom. The former, i.e. the hopper car, has a floor sloping downward from each end and in some cars from the sides also. The amount of freight to be carried depends upon the size of the floor space and the height of the sides and ends of the car to be used. Therefore we distinguish low-sided and high-sided wagons as well as low –capacity or high-capacity ones. Both hoppers and gondolas are used to carry stone, gravel, crushed rock and other bulky materials which may be exposed to weather.
A type of car that is not very old but has become very popular is the covered hopper car. It looks like a conventional hopper but it is roofed. To load or fill the car you use water-tight hatches in its roof and you empty or unload it through its hopper bottom. It is much cheaper to carry bulky materials that cannot be exposed to weather such as cement, dry powdered chemicals, etc., in these cars than to place them in bags and ship the bags in special cars.
Вопросы к тексту:
- For what are special types of cars required?
- What is the most widely used type of freight cars?
- For what are hoppers and gondolas used?
- What type of cars has become very popular?
Задание №2. Переведите следующие словосочетания на русский язык:
wheelbase, brakes, emergency, partition, for passing with safety, by making the trucks very strong, the absence of signaling, the danger of travelling, the car lighting and heating systems, the most uncomfortable car seats, the fastest way of transportation.
Вариант №9
Задание №1
