I. Use the following words and phrases in sentences of your own:
to rust, alloying elements, to resist, to escape, stainless steel, carbon steel, machine steel, alloy steel, to fuse, corrosion, refractory, rust-resistant steel, heat-resistant steel, green sand moulds, pattern, strain
II. Answer the following questions:
1. What is steel? 2. What are the main types of steel depending on the carbon content? 3. What steels are most widely used in industry? 4. What manufacturing purposes may tool steel be used for? 5. What is alloy steel? 6. What alloying elements can change the properties of alloy steel0 7. What sand is used for making steel castings? 8. Why must the pattern be a little larger than the casting which is to be produced? 9. What does the tensile strength of steel depend on?
III. Find in the text verbs for the following nouns:
division, casting, difference, fusion, solidification, improvement, requirement, production
IV. Translate the following sentences into Russian and observe the different ways of expressing obligation:
1. Steel has to be widely used in machine-building because of its high strength. 2. Alloy steel must be made by adding some alloying elements. 3. Tools made of high-speed steel may do the work at much higher speeds than carbon tool steels. 4. Chromium and tungsten are to increase the hardness and strength of steel. 5. High carbon steel should be hardened by heating it to a certain temperature and then quickly cooling in water. 6. Special alloy steels can be used for parts requiring great wear resistance.
V. Connect the following sentences Absolute Participle Constructions and translate the sentences into Russian:
Example: 1. Steel is one of the strongest metals.
We use steel for products where great Strength is required
Steel being one of the strongest metals, we useit for products where great strength is required. – Так как сталь является одним изсамыхпрочных металлов, мы используем её для производства изделий, которые требуют большую прочность.
2. Alloying elements for making steel are nickel, chromium, manganese,etc. Nickel increases strength and hardness of the steel. Alloying elements for making steel are nickel, chromium, manganese, nickel increasing strength and hardness of the steel. –Сплавляемыми элементами производства стали являются никель, хром, магнезии и другие, причём никель увеличивает прочность и твердость стали.
1. Alloy steels are ever wider used in industry. Manufacturing methods are changed. 2. The metal is poured at an extremely high temperature. The sand used for making moulds for steel castings should be refractory. 3. Steel is a very strong material. We find wide application of steel in engineering. 4. Heat-resistant steel is made by adding some tungsten and molybdenum. Manganese increases the wear resistance. 5. Steel and cast iron differ in carbon content. The carbon content of steel is little, while that of cast iron is much greater. 6. Some alloying elements make steel rust-resistant. Such steels are called stainless steels.
VI. Underline the suffixes and translate into Russian the following groups of words:
Strong, strength; addition; appreciable, appreciation; de fine, definite, definition; form, formation, former, formerly; vibrate, vibration, vibrator, vibratory
VII. (a) Read and translate the following text without using a dictionary:
PRODUCTION OF STEEL
Converter steel is made from molten pig iron by forcing a blast of cold air under great pressure through the metal. The converter represents a large tank made of steel and covered with refractory bricks with an open top through which the molten metal is poured into the converter and out of it. When forcing the blast of cold air through the melted metal, the oxygen contained in the air combines with the carbon of the pig iron, and almost all the carbon in the metal is turned out. Steel made by this method is very cheap, but it is low grade steel because this method of producing steel cannot be well controlled.
Steel made in this way is called "Bessemer steel". One ton of such steel can be made in one minute.
(b) On the basis of the text make up three questions and answer them
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