Text c Basic Oxygen Process

The oldest process for making steel in large quantities, the Bessemer process, made use of a tall, pear-shaped furnace, called a Bessemer converter that could be tilted sideways for charging and pouring. Great quantities of air were blown through the molten metal; its oxygen united chemically with the impurities and carried them off.

In the basic oxygen process, steel is also refined in a pear-shaped furnace that tilts sideways for charging and pouring. Air, however, has been replaced by a high-pressure stream of nearly pure oxygen. After the furnace has been charged and turned upright, an oxygen lance is lowered into it. The water-cooled tip of the lance is usually about 2 m above the charge although this distance can be varied according to requirements. Thousands of cubic meters of oxygen are blown into the furnace at supersonic speed. The oxygen combines with carbon and other unwanted elements and starts a high-temperature churning reaction that rapidly burns out impurities from the pig iron and converts it into steel. The refining process takes 50 min or less; approximately 275 metric tons of steel can be made in an hour.

Exercise 1

Ответьте на следующие вопросы:

1. What is the oldest process for making steel in large quantities?

2. Can you describe the Bessemer converter?

3. What is the function of the air Bessemer process?

4. Has air been replaced in basic oxygen process by hydrogen or other material?

5. What is lowered into the furnace after the furnace is charged and ready to start operation?

6. What is the approximate distance of the water-cooled tip of the lance above the charge?

7. Does the refining process take more than two hour to finish the Bessemer process?

8. What volume of steel can be made in an hour time in Bessemer converter?

Exercise 2

Заполните пропуски недостающими по смыслу словами, используя текст:

1. The Bessemer process is the oldest process for making … in large quantities.

2. A tall, pear-shaped furnace is called a Bessemer … .

3. The Bessemer converter can be … sideways for charging and …

4. Great quantities of … have to be blown through the molten metal during the Bessemer process.

5. In Bessemer process oxygen unites chemically with the … and carries them off.

6. In the basic … … steel is also refined in a pear-shaped furnace that tilts sideways for charging and pouring.

7. After the furnace is charged and turned upright, an oxygen … is lowered into it.

8. Thousands of cubic meters of … are blown into the furnace at supersonic speed.

9. The oxygen combines with … and other unwanted elements and starts a high-temperature churning reaction.

Exercise 3

Соответствуют ли данные предложения содержанию текста:

1. The latest process for making steel in large quantities is called the Bessemer process.

2. Very limited quantities of air are blown through the molten metal in the Bessemer process.

3. In the basic oxygen process, steel is also rolled into sheets.

4. The oil-cooled tip of the lance is usually about 2 m above the charge.

5. Thousands of cubic meters of hydrogen are blown into the furnace at normal speed.

6. In the Bessemer process the oxygen combines with carbon and other unwanted elements.

7. The refining process in Bessemer converter takes 50 min or less.

8. Approximately 1275 metric tons of steel can be made in an hour.

Exercise 4

Используя текст, составьте высказывания с данными словами и выражениями:

charging and pouring - basic oxygen process - high-pressure stream - pure oxygen – to turn upright - supersonic speed - unwanted elements - to burn out impurities - refining process.

Exercise 5

Кратко передайте содержание каждого абзаца.

Exercise 6

Выделите пять основных идей текста.

Exercise 7

Составьте предложения, используя данные выражения:

To carry out impurities – to blow air through –to tilt sideways - molten metal – to unite chemically - basic oxygen process – to turn upright – to vary according to requirements - supersonic speed – to combine with smth. – to burn out - refining process.

Exercise 8

Переведите на русский язык следующие предложения:

1. The Bessemer process is the first method discovered for mass-producing steel.

2. Sir Henry Bessemer of England began experiments aimed at developing a revolutionary means of removing impurities from pig iron by an air blast.

3. The scientist found that adding an alloy of carbon, manganese, and iron after the air-blowing was complete restored the carbon content of the steel while neutralizing the effect of remaining impurities, notably sulfur.

4. The Bessemer converter is a cylindrical steel pot approximately 6 m. high, originally lined with a siliceous refractory.

5. The original Bessemer converter was not effective in removing the phosphorus present in sizable amounts in most British and European iron ore.

6. Bessemer converter could be tilted sideways for charging and pouring.

7. Great quantities of air were blown through the molten metal; its oxygen united chemically with the impurities and carried them off.

Exercise 9

Переведите на английский язык:

1. Cамым старым методом плавки стали в больших объемах является Бессемеровский метод.

2. Огромное количество воздуха продувается через расплавленный металл при Бессемеровском методе плавки

3. В процессе плавки кислород химически соединяется с углеродом и примесями и выводит их из металла.

4. В процессе развития конвертерного производства стали, воздух был заменен кислородом, подаваемый в печь, под высоким давлением.

5. Загрузка и выгрузка печи осуществляется путем ее наклона в сторону.

6. Охлаждаемый водой наконечник трубки – обычно находится на высоте приблизительно 2 метров выше уровня загрузки.

7. В кислородно-конвертерном процессе производства стали, тысячи кубических метров кислорода вдуваются в печь на сверхзвуковой скорости.

8. В кислородно-конвертерном процессе, кислород соединяется с углеродом и другими нежелательными примесями, быстро сжигает примеси чугуна и конвертирует его в сталь.

Exercise 10

Текст на самостоятельный перевод:

Open-Hearth Process

Essentially the production of steel from pig iron by any process consists of burning out the excess carbon and other impurities present in the iron. One difficulty in the manufacture of steel is its high melting point, about 1370° C, which prevents the use of ordinary fuels and furnaces. To overcome this difficulty the open-hearth furnace was developed; this furnace can be operated at a high temperature by regenerative preheating of the fuel gas and air used for combustion in the furnace. In regenerative preheating, the exhaust gases from the furnace are drawn through one of a series of chambers containing a mass of brickwork and give up most of their heat to the bricks. Then the flow through the furnace is reversed and the fuel and air pass through the heated chambers and are warmed by the bricks. Through this method open-hearth furnaces can reach temperatures as high as 1650° C. The furnace itself consists typically of a flat, rectangular brick hearth about 6 m by 10 m, which is roofed over at a height of about 2.5 m. In front of the hearth a series of doors opens out onto a working floor in front of the hearth. The entire hearth and working floor are one story above ground level, and the heat-regenerating chambers of the furnace take up the space under the hearth. A furnace of this size produces about 100 metric tons of steel every 11 hr. The furnace is charged with a mixture of pig iron (either molten or cold), scrap steel, and iron ore that provides additional oxygen. Limestone is added for flux and fluorspar to make the slag more fluid. The proportions of the charge vary within wide limits, but a typical charge might consist of 56,750 kg of scrap steel, 11,350 kg of cold pig iron, 45,400 kg of molten pig iron, 11,800 kg of limestone, 900 kg of iron ore, and 230 kg of fluorspar. After the furnace has been charged, the furnace is lighted and the flames play back and forth over the hearth as their direction is reversed by the operator to provide heat regeneration. Chemically the action of the open-hearth furnace consists of lowering the carbon content of the charge by oxidization and of removing such impurities as silicon, phosphorus, manganese, and sulfur, which combine with the limestone to form slag. These reactions take place while the metal in the furnace is at melting heat, and the furnace is held between 1540° and 1650° C for many hours until the molten metal has the desired carbon content. Experienced open-hearth operators can often judge the carbon content of the metal by its appearance, but the melt is usually tested by withdrawing a small amount of metal from the furnace, cooling it, and subjecting it to physical examination or chemical analysis. When the carbon content of the melt reaches the desired level, the furnace is tapped through a hole at the rear. The molten steel then flows through a short trough to a large ladle set below the furnace at ground level. From the ladle the steel is poured into cast-iron molds that form ingots usually about 1.5 m long and 48 cm square. These ingots, the raw material for all forms of fabricated steel, weigh approximately 2.25 metric tons in this size. Recently, methods have been put into practice for the continuous processing of steel without first having to go through the process of casting ingots.