- •I предисловие
- •Vocabulary notes
- •Vocabulary notes
- •Find international words in the text.
- •Find English equivalents for the following
- •3. Match the English words and word combinations given below with the Russian equivalents
- •4. Answer the following questions
- •5. Translate the passage of the text beginning with «When Ghritopher Columbus...» to «... Particularly silver» in writing.
- •Metals and alloys
- •3. Match the English words and word combinations given below with the Russian equivalents
- •4. Answer the following questions
- •Bronze and brass
- •Vocabulary notes
- •If mixed with tin if you had been a soldier to straighten sword
- •Improvement to bend
- •1. Answer the following questions
- •2. Match the words on the left with their definitions on
- •3. Find out which sentences correspond to the contents of the text
- •4. Render the following
- •5. Translate at sight
- •1, Answer the following questions
- •2. Find out which sentences correspond to the contents of the text
- •3. Match the words on the left with their definitions on the right
- •1. Answer the following questions
- •4. Render the following
- •5. Translate at sight
- •2. Match the words on the left with their definitions on the right
- •3. Find out which sentences correspond to the contents of the text
- •4. Render the following
- •1. Answer the following questions
- •2. Match the words on the left with their definitions on the right
- •1. Answer the following questions
- •2. Match the words on the left with their definitions on the right
- •Metal handling
- •3. Look up in the Polytechnical or Metallurgical dictionaries to find some other types of pouring metal in addition to those given ** the text. Give their definitions.
- •4. Find out which sentences do not correspond to the contents of the text
- •Read the following text and find the answers to the question below
- •7. Translate at sight
- •Shell moulding
- •1. Answer the following questions
- •2. Match the words on the left with their definitions on the right
- •4. Read the following text and find the answers to the questions below
- •Give the title to the text above.
- •Use your translation of 4 in describing the process of «Shell Moulding» as compared with «Sand Moulding».
- •Translate at sight
- •Investment casting
- •1. Answer the following questions
- •Translate at sight
- •1. Answer the following questions
- •2. Match the words on the left with their definitions on the right
- •3. Find out which sentences do not correspond to the contents ofthe text
- •4. Read the text and
- •2. Match the words on the left with their definitions on the right
- •Fibre direction
- •Match the words on the left with their definitions on the right
- •1. Answer the following questions
- •2. Find the English equivalents for the following Russian word combinations
- •3. Match the words on the left with their definitions on the right
- •4. Translate at sight
- •3. Translate at sight
- •1. Answer the following questions
- •2. Find the English equivalents for the following Russian word combinations
- •3. Translate at sight
- •Impact pressure squeeze pressure production
- •5. What do these descriptions refer to
- •Find the key terms in the part of the text «Simple Structure of steel», beginning with «When this cementite is formed...» and to the end of the text. Give their definitions.
- •Make up a summary of the text above.
- •Retell the text «Quenching and Tempering» using the answers to the questions from 1 as a plan.
- •Read the text
- •Find in the text above two coupling terms. Give their definitions.
- •Give a title to the text.
- •Make up an abstract of the text «Hardening» in writing.
- •6. Say what these statements have to do with. Paraphrase them using the words from the text above. Start each answer in this way, «This statement has to do with...»
- •Make up a summary of the text.
- •2. Find in the text «The Sintering Process» synonyms for the following
- •Design rules
- •6. Prepare a report on the topic «The Powder Metallurgy Process» taking in Units 29-33. Use the word combinations from Chapter 3, Appendix 4 «English for Scientific Discussions».
- •Industrial mould-casting processes
- •Introduction
- •Is to do with...
- •Is devoted to...
- •7. Referring to visual aids
- •9. Inviting questions
- •I contents
2. Match the words on the left with their definitions on the right
1) shell a) the solid product of the dry distil-
lation of coal
charge b) a furnace for melting cast iron
cupola c) the steel plate envelope encasing a
furnace
4) ingot d) the material prepared for introduc-
ing into a foundry furnace
5) coke e) refractory or metal vessel with a
flat bottom designed for melting metal in a furnace
6) crucible f) a block of metal cast in a metal
mould
3. Find out which sentences correspond to the contents of the text
Open-hearth furnace is the most widely and the most economical type of furnaces used for melting iron.
The cupola consists of a conic shell lined with refractory brick with the bottom door opened,
The rate or melting in tons per hour is a function of the diameter of the furnace.
Electric-arc furnaces produce metal in batches.
The furnace is tapped when the proper composition of metal is achieved.
Heat is provided by five electrodes striking an arch against the cold metal charge.
4. Render the following
The cupola is the oldest type of furnaces and the most economical one. It is a cylindrical shell lined with refractory brick. The cupola is charged through the door in the upper part of the shell. Air is blown in through the tuyeres near the bottom to burn the coke.
The open-hearth process is one of the most important methods of making steel. It is easy to control and for that reason it is more frequently used. The furnace is lined with fire brick to withstand the very high temperatures used. The charge consists of molten iron, steel, scrap, some hematite and lime.
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Расплавление чугуна производится в вагранках, простых печах, состоящих из цилиндрического корпуса, облицованного огнеупорным кирпичом. Шихта состоит из чередующихся слоев кокса и чугуна. В шихту добавляют немного извести. Мартеновские печи используются для производства стали. Процесс в мартеновской печи легко контролировать. Шихта обычно подается манипулятором. Металл плавится под действием горячих газов и нагретого воздуха. Сталь производится также и в электрических печах. Электричество используется для получения нужной температуры. Существуют дуговые
Unit 5
STEEL MELTING
In the order of tonnages produced by each furnace, open-hearth, direct arc electric, an electric induction are the most popular melting equipment for steel castings.
In some cases, open-hearth melting is the most economical. However, in localities, where power rates are reasonably low, and where there is an abundant supply of chips, turnings and other scrap which cannot be used in the open-hearth, the direct-arc electric may produce steel at lower cost. Maintenance costs are considerably lower for electric furnaces. Generally, the control in an electric furnace is more precise, and higher quality levels are more attainable than in an open-hearth. This is particularly true for various grades of alloy steel.
The degree and quality of control of chemistry and temperature are extremely critical in producing high-quality steel castings. With adequate control it is possible to hold to very precise specifications. However, there are great differences among steel foundries in the degree of control attainable with the melting equipment in place. Therefore, the user of steel castings needs to investigate fully this aspect of a foundry's competence.
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Exercises