Технический перевод иностранной литературы по профилю подготовки. Учебное пособие

Notch toughness – The nature of steel material is that it contains some imperfections, albeit of very small size. When subject to tensile stress these imperfections tend to open. If the steel were insufficiently tough, the ‘crack’ would propagate rapidly, without plastic deformation, and failure would result. This is called ‘brittle fracture’ and is of particular concern because of the sudden nature of failure. The toughness of the steel, and its ability to resist this behavior, decreases as the temperature decreases. The requirement for toughness increases with the thickness of the material. Hence, thick plates in cold climates need to be much tougher than thin plates in moderate climates. Toughness is specified by requiring minimum energy absorption in a Charpy V-notch impact test, which is carried out with the specimen at a specified (low) temperature and the requirement is given as part of the grade designation.

Weldability – All structural steels are essentially weldable. However, welding involves laying down molten metal and local heating of the steel material. The weld metal cools quickly because the material offers a large ‘heat sink’ and the weld is relatively small. This can lead to hardening of the ‘heat affected zone’ of the material adjacent to the weld pool and to the reduced toughness (often called embrittlement). The greater the thickness of material, the greater is the reduction of toughness. The susceptibility to embrittlement also depends on the quantity and nature of the alloying elements, principally the carbon content. This susceptibility can be expressed as the carbon equivalent value (Ceq), and the material standards give an expression for determining this value. The higher the Ceq, the more difficult it is to weld. Weld procedure specifications are drawn up that set out the necessary welding parameters for any particular steel grade and weld type, to avoid embrittlement.

DEVELOPING ACADEMIC VOCABULARY

WORKING OUT THE MEANING OF UNKNOWN WORDS

TASK 3. THE FOLLOWING WORDS ARE ALL FROM THE TEXT ABOVE. FIND THEM IN THE TEXT:

ductility slightly fatigue deflection localize onset

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TASK 4. FOR EACH WORD, READ THE SENTENCE IT OCCURS IN AND ANSWER THE QUESTIONS:

a)Is the word positive, negative or neutral?

b)Is it a noun, adjective, adverb or verb?

c)Can you think of a word with a similar meaning (synonym) and one with an opposite meaning (antonym)?

TASK 5. CREATE THE GLOSSARY FOR THE TEXT.COMPLETE THE TABLE:

READING COMPREHENTION

TASK 6. ANSWER THE QUESTIONS:

1. What are the principal properties of steels of interest to the designer?

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2.What does yield strength reduce slightly with ?

3.Why are steels of 350 N/sq mm yield strength predominantly used in bridge applications?

4.What other advantages may higher strength steels offer ?

5.What is ductility?

6.What ability does good ductility offer?

7.What happens to steel when it is subjected to tensile stress?

8.What is called «brittle fracture»?

9.What happens to steel when temperature decreases?

10.What does welding involve?

11.What does the susceptibility to embrittlement depends on?

TASK 7. GIVE THE ENGLISH EQUIVALENTS OF THE FOLLOWING WORDS AND WORD COMBINATIONS:

1.возможный излом

2.перераспределять напряжение высокой концентрации

3.без сбоев

4.момент, вызывающий образование пластических шарниров

5.напряжение растяжения

6.быстро распространяться

7.хрупкое разрушение

8.поглощение энергии

TASK 8. MAKE UP 8 SENTENCES OF YOUR OWN USING THE WORDS AND WORD COMBINATIONS ABOVE.

TASK 9. COMPLETE THE SENTENCES:

1.The principal properties of steels of interest to the designer are …

2.The yield strength is the most significant property …

3.Yield strength reduces slightly with …

4.Ductility is a measure of the degree …

5.Good ductility offers the ability to redistribute …

6.Notch toughness of steel is …

7.Welding of steels involves …

8.Weld procedure specifications are drawn up to avoid …

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SPEAKING

TASK 10. RETELL THE TEXT. USE TASK 9 AS A PLAN.

TASK 11. TRANSLATE THE TEXT USING THE GLOSSARY.

GRAMMAR FOCUS

Comparative and superlative adjectives and adverbs. Revision.

TASK 12. TRANSLATE THE SENTENCES FROM THE TEXT, PAYING ATTENTION TO THE WORDS IN ITALICS.

LISTENING COMPREHENTION

TASK 13. LISTEN TO THE TEXT AND COMPLETE THE TRANSCRIPT:

Chemical and electrochemical … … is the best in stainless steel, second only to titanium.

As for physical properties of stainless steel, … resistance, high temperature resistance, low temperature resistance and even ultra-low temperature resistance should be mentioned.

Mechanical properties of … steels vary according to its type. Martensitic stainless steel has high … and hardness and is suitable for manufacturing parts that are both corrosion resistant and … high strength and high … resistance, such as turbine shafts, stainless steel … , and stainless steel bearings. Austenitic stainless steel has good … . It is not very high in strength, but its corrosion resistance is the best in stainless steel. It can be used as … materials in occasions that require very good corrosion resistance and low mechanical properties, such as chemical plants, … plants, sulfuric acid, hydrochloric acid manufacturers. Of course, it can also be used in the … industry such as submarines. Ferritic stainless steel has … mechanical properties and is not very strong in strength yet it is resistant to oxidation and is suitable for various industrial … parts.

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TEXT 12. STEEL PRODUCTS USED IN THE CONSTRUCTION OF BRIDGES

TASK 1. BEFORE YOU READ:

1.What do you know about the steel products used for the construction of bridges?

2.Can you name them?

TASK 2. READ THE TEXT:

Steel products like plates, hot rolled sections (beams, channels, angles etc.), steel cables, and hollow sections are used in the construction of bridges.

In hot rolled sections universal beams are the most used section. These beams can be fabricated or rolled but rolled beams are normally preferred.

Steel cables used in bridge construction are generally referred to as bridge strand or bridge rope. They are constructed from individual colddrawn wires that are spirally wound around a wire core. The nominal diameter can be specified between 15 mm and 100 mm depending on the intended application. Strands and cables are almost always galvanized for use in bridges where internal corrosion between the wires is a possibility. Because cables are an assemblage of wires, it is difficult to define yield strength for the assembly. Therefore, the capacity is defined as the minimum breaking strength that depends on the nominal diameter of the cables. Since cables are axial tension members, the axial stiffness needs to be accurately known for most bridge applications. Because relative deformation between the individual wires affect elongation, bridge strand and rope is pre-loaded to about 55 % of the breaking strength after manufacturing to “seat” the wires and stabilize the deformation response. Following pre-loading, the axial deformation becomes linear and predictable based on an effective modulus for the wire bundles. Bridge rope has an elastic modulus of 140 N/sq mm. The elastic modulus of bridge strand is 165 N/sq mm.

Hollow structural sections (HSS) are commonly used in building construction and they can be considered as an option for some bridge members. Increased lateral bending and torsional resistance can make them an attractive option for cross bracing and other secondary members subjected to compression. HSS have also been used to fabricate trusses used for pedes-

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trian bridges that are subject to lower fatigue loading. HSS commonly refers to cold-formed welded or seamless structural steel tubing. The minimum specified yield and tensile strengths of 350 N/sq mm and 430 N/sq mm, respectively. The shapes are usually formed by cold bending carbon steel plate into the required shape and making a longitudinal seam weld along the length. Both round and rectangular shapes are available with various cross sections and wall thicknesses. The suitability of HSS for bridge members subject to the fatigue and fracture limit states has not been established. Cold bending of the corners of rectangular shapes can lead to reduced notch toughness in the corner regions. Another possible concern for bridge use is the need to control internal corrosion within the tubes, since the interior of the tube cannot be accessed for visual inspection.

DEVELOPING ACADEMIC VOCABULARY

WORKING OUT THE MEANING OF UNKNOWN WORDS

TASK 3.THE FOLLOWING WORDS ARE ALL FROM THE TEXT ABOVE. FIND THEM IN THE TEXT:

hollow spirally wire assembly nominal axial

TASK 4. FOR EACH WORD, READ THE SENTENCE IT OCCURS IN AND ANSWER THE QUESTIONS:

a)Is the word positive, negative or neutral?

b)Is it a noun, adjective, adverb or verb?

c)Can you think of a word with a similar meaning (synonym) and one with an opposite meaning (antonym)?

TASK 5. CREATE THE GLOSSARY FOR THE TEXT.COMPLETE THE TABLE:

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to roll a cable

bridge strand cold-drawn wires a wire cord elongation

deformation response linear

wire bundles torsional cross bracing truss

longitudinal seam weld rectangular

fatigue fracture limit cold bending

notch toughness

READING COMPREHENTION

TASK 6. ANSWER THE QUESTIONS:

1.What steel products are used in the construction of bridges?

2.What are bridge strand or bridge ropes constructed from?

3.Why are strands and cables almost always galvanized for use in bridges?

4.Why is it difficult to define yield strength for the assembly?

5.Why does the axial stiffness need to be accurately known for most bridge applications?

6.Why is bridge strand and rope pre-loaded to about 55 % of the breaking strength after manufacturing?

7.What makes hollow structural sections an attractive option for cross bracing and other secondary members subjected to compression?

8.How are the shapes usually formed?

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TASK 7. GIVE THE ENGLISH EQUIVALENTS OF THE FOLLOWING WORDS AND WORD COMBINATIONS:

1.разрывное усилие

2.продольный сварной шов

3.мотки

4.холоднотянутая проволока

5.внутренняя коррозия

6.предел текучести

7.осевое растяжение

8.осевая жесткость

TASK 8. MAKE UP 8 SENTENCES OF YOUR OWN USING THE WORDS AND WORD COMBINATIONS ABOVE.

TASK 9. COMPLETE THE SENTENCES:

1.Steel products like … are used in the construction of bridges.

2.Universal beams are the most used sections …

3.Bridge strand or bridge ropes are …

4.They are constructed from …

5.Strands and cables are almost always galvanized for use in bridges because …

6.It is difficult to define yield strength for the assembly because …

7.The axial stiffness needs to be accurately known for most bridge applications because …

8.Hollow structural sections (HSS) are commonly used in building construction and …

SPEAKING

TASK 10. RETELL THE TEXT. USE TASK 9 AS A PLAN.

TASK 11. TRANSLATE THE TEXT USING THE GLOSSARY.

GRAMMAR FOCUS

NOUN PHRASES

The meaning of a noun can be made more precise by the words immediately before or after it. These words and the noun together are called the noun phrase. Pre-modifying words help to describe the noun.

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e.g. resource extraction, production line.

In academic writing, noun + noun phrases are common because they contain a lot of information in a shorter phrase:

satellite systems (Compare: systems that are based on a network of satellites) communication devices (Compare: devices that are used for communication) You can use noun+ noun phrase to help you paraphrase the text. Compare:

Many young people use texting as their main method of communicating with each other.

The main communication method among many young people is texting.

TASK 12. TRANSLATE INTO RUSSIAN, PAYING ATTENTION TO NOUN PHRASES:

A human mind, a factory inspector, a carbon nanotube, a space flight report, tumor tissue, a dictionary reference, citation index, design goals, a functional parameter list, , labor productivity increase, shape memory alloys, cable TV, quantum dots, chemistry laboratory, cancer nanotechnology, laptop computer, gene engineering, multi-cylinder engine, large-scale work, laboratory assistant, drug therapy, computer centre, the environment protection, a square mile, education system, energy source, cancer treatment therapy, four-wheel control system, large-scale work, the land transport improvement problem, the traffic speed increase, , the house ventilation facilities, arch bridge construction site, thermoelectric generator development, flight control equipment, spare parts list, a requirement document, nanoscale devices.

TASK 13.TRANSLATE INTO ENGLISH :

1.загрязнение воздуха

2.потребление энергии

3.производительность труда

4.космический полет

5.реконструкция железнодорожного моста

6.человеческий фактор

7.проблема улучшения наземного транспорта

8.компьютер третьего поколения

9.образовательная система

10.углеродные нанотрубки

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TASK 14. TRANSLATE THE PHRASES FROM THE TEXT GIVEN IN ITALICS.

LISTENING COMPREHENTION

TASK 15. LISTEN TO THE TEXT AND CORRECT THE MISTAKES IN THE NOTES:

1.There are special surgical steels used for medical devices.

2.There are several important reasons for the development of special surgical steels.

3.Most non-implant medical devices are produced from commercial grade stainless steels.

4.Stainless steels do not always adequately meet clinical requirements.

5.There are special implant steels nowadays.

6.To produce implant steels special production routes are required.

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