Find the following words and word combinations in the text свойства металлов решение
1. При волочении проволоки диаметр отверстия волочильной доски каждый раз уменьшается.
2. Штамповка листового металла включает в себя ковку, изгиб и обрезку.
3. Небольшая деформация листа при растяжении помогает сохранить новую форму детали.
4. Изменение формы при штамповке производится путем сжатия между двумя штампами.
5. Края листа при штамповке отрезаются для получения конечных размеров.
6. При проковке деталь должна быть горячей для уменьшения необходимых усилий и увеличения пластичности металла.
7. После ковки в закрытых штампах детали не требуют большой механической обработки.
8. При чеканке деформация металла невелика и отпечаток формируется на поверхности металла.
9. Высадка используется для изготовления головок гвоздей и болтов.
UNIT III.
METALS AND METALWORKING
Exercise 3.1. Read and translate the texte. Answer the questions on the texte:
1. Why are metals so important in industry?
2. What are the main metalworking processes?
3. Why are metals worked mostly hot?
4. What properties does cold working give to metals?
5. What is rolling? Where is it used?
6. What is extrusion? What shapes can be obtained after extrusion?
7. What are the types of extrusion?
TEXT A: « METALWORKING»
Metals are important in industry because they can be easily deformed into useful shapes. A lot of metalworking processes have been developed for certain applications. They can be divided into five broad groups:
5. sheet-metal forming.
During the first four processes metal is subjected to large amounts of strain (deformation). But if deformation goes at a high temperature, the metal will recrystallize — that is, new strain-free grains will grow instead of deformed grains. For this reason metals are usually rolled, extruded, drawn, or forged above their recrystallization temperature. This is called hot working. Under these conditions there is no limit to the compressive plastic strain to which the metal can be subjected.
Other processes are performed below the recrystalli-zation temperature. These are called cold working. Cold working hardens metal and makes the part stronger. However, there is a limit to the strain before a cold part cracks.
Учебно-методическое пособие предназначено для подготовки и проведения практических занятий по дисциплине «ОГСЭ.03 Английский язык» в учреждениях среднего и начального профессионального образования. Пособие разработано для студентов специальности 22.02.02 Металлургия цветных металлов и соответствуют требованиям программы по данной дисциплине.
Целями данного учебно-методического являются:
- расширение потенциального словаря профессиональной лексики;
- формирование у студентов навыков устной речи по профессиональной тематике, в
различных контекстах профессиональной направленности;
- развитие потребности и умения пользоваться справочной литературой
- развитие навыков чтения с полным пониманием основного содержания текстов
- активизация знания грамматических форм и синтаксических оборотов,
употребителяемых в специальной профессиональной литературе.
В учебно-методическом пособии по дисциплине представлены тематические текстовые материалы для закрепления навыка перевода технических текстов с целью извлечения необходимой информации, задания на закрепление лексических навыков, упражнения на расширение словарного запаса и образование потенциального профессионального словаря, тренировочные задания для активизации знаний грамматических форм и синтаксических оборотов.
Пособие сопровождается приложением – словарем химических терминов, таблицами, схемами, а также условными обозначениями:
VOCABULARY- лексический минимум по теме,
EXERCISES –упражнения на закрепление лексических навыков,
TEXT – тексты профессионального характера,
Exercise - тренировочные задания для активизации знаний грамматических форм
Согласно ФГОС специальности 22.02.02 Металлургия цветных металлов студенты должны уметь:
- общаться (устно и письменно) на иностранном языке на профессиональные и повседневные темы;
- переводить (со словарем) иностранные тексты профессиональной направленности;
- самостоятельно совершенствовать устную и письменную речь, пополнять словарный запас;
- лексический (1200 - 1400 лексических единиц) и грамматический минимум, необходимый для чтения и перевода (со словарем) иностранных текстов профессиональной направленности.
Пособие может быть использовано для самостоятельной работы студентов.
HISTORY OF METALLURGY.
| art - зд. ремесло in ancient times– в ранние времена, в старину within the last century –за последнее столетие has made it possible –сделало возможным in this broader sence falls into –в этом более широком значении делится на deals with -рассматривает |
Metallurgy is one of the oldest of arts but one of the youngest of sciences. Many of our metals were known in ancient times, but it is only within the last century or two that the knowledge of the properties of the metals has made it possible to apply them in any extended way for industrial purposes.
With the development of physics of metals, metallography, theory of heat treatment, and other phases of the science of metals, the field of metallurgy has broadened.
Physical metallurgy deals with the nature, structure, and physical properties of metals and alloys.
Mechanical metallurgy includes the processes of working and shaping metals — processes which do not involve chemical changes.
EXERCISES
Exercise 1. Find in the text the English equivalents of these Russian word combinations.
Reliability is a basic requirement, plant or machine. The most ingenious machine is nothing but useless unless it is reliable.
At present the main defect in any machine is the different service life of its parts. The first to break down are parts with friction, the most numerous in any machine. Until quite recently scientists differed in there explanations of why parts subjected to friction break.
At present scientists are engaged in research into friction and were-and-tear resistance. The results of their comprehensive research will extend the useful life of units with friction by thirty to fifty percent as compared with what we have now.
Sufficient reliability and long service life of highly complicated automatic complexes, spaceships and assembly lines can be ensured by the high quality of their components, their accurate assembly and continuous checking while in operation, as well as by detecting faults as soon as they appear. This means that instruments are necessary for checking metal billets; all kinds of test installations and multiple switching control devices by which temperature, pressure and density in any part of a system may be inspected a number of times over a period of only one second. We need diagnostic system and many different types of flaw detectors and sensors because, as is known, reliability is the key which opens the way to large-scale automation.
Why is the service life of different machine parts different?
What factors do the service life and reliability of complicated systems depend on?
In what ways can the quality of machine parts be inspected?
A major advance in twentieth century manufacturing was the development of mass production techniques. Mass refers to manufacturing process in which an assembly line, usually a conveyer belt, moves the product to stations where each worker performs a limited number of operations until the product is assembled. In the automobile assembly plant such systems have reached a highly-developed form. A complex system of conveyer belts and chain drives car parts to workers who perform the thousands of necessary assembling tasks.
Mass production increases efficiency and productivity to a point beyond which the monotony of repeating an operation over and over slows down the workers. Many ways have been tried to increase productivity on assembly lines: some of them are as superficial as piping music into the plant or painting the industrial apparatus in bright colours; others entail giving workers more variety in their tasks and more responsibility for the product.
These human factors are important considerations for industrial engineers who must try to balance an efficient system of manufacturing with the complex needs of workers.
Another factor for the industrial engineer to consider is whether each manufacturing process can be automated in whole or in part. Automation is a word coined in the 1940s to describe process by which machines do tasks previously performed by people. The word was new but the idea was not. We know of the advance in the development of steam engines that produced automatic valves. Long before that, during the Middle Ages, windmills had been made to turn by taking advantage of changes in the wind by means of devices that worked automatically.
Automation was first applied to industry in continuous-process manufacturing such as refining petroleum, making petrochemicals, and refining steel. A later development was computer-controlled automation of assembly line manufacturing, especially those in which quality control was an important factor.
Text D. FIVE BASIC TECHNIQUES
The variety and combination of machine tools are unlimited today. Some are small and may be mounted on a workbench. Others are so large that are housed in special buildings.
Large or small machine tools can be classified in five main groups ac cording to the five basic techniques of shaping metal. These basic operations in clude drilling and boring (including reaming and tapping), turning, milling, planning (including shaping and broaching) and grinding (including honing). Each machine performs one or more of these operations. Variations of five basic techniques are used for special situations. There are, for example, machines that combine two of these techniques, as in a boring, drilling and milling machine or a combination of milling and planning machine.
In addition to the five basic techniques there are newer metal shaping methods developed during the past two decades. These new methods employ corrosion, erosion and force characteristics of chemicals, electricity, magnetism, liquids, sound and light.
Drilling and boring. Drilling is a basic machine shop technique. It consists of cutting a round hole by means of a rotating drill. Boring, on the other hand, is the process of finishing a hole already drilled by means of a rotating single-point tool. On some boring machines, the tool is in a fixed position and the work re volves; on others the work is held fixed and the tool revolves.
How may groups can machine tools be classified?
What basic operations of shaping metal do machine tools include?
What new metal shaping methods were developed during the past two decades?
What do these new methods employ?
What is drilling?
What is boring?
What differs drilling machines from boring machines?
What is the difference between reaming and tapping?
1. Forging is one of the leading technological processes of modern industry.
2. These machines were built up by the workers of our plant for three hours.
3. All these forged parts were made of different materials.
4. The students of the machine-building industry were shown various manufacturing processes.
5. This part was made of steel by casting
6. The main parts of these machines were produced by forging.
7. The machine-building plant of our town produces these machine-tools (металлорежущие станки).
8. The loss of metal in chips in forging process is reduced.
9. The selecting of the most suitable method of forging entails the minimum consumption of metal.
10. The art of drawing metal has developed very rapidly in the last 20 years.
UNIT 2
Text A: METALS
Text B: STEEL
Text C: METHODS of STEEL HEAT TREATMENT
Text A: METALS
Metals are materials most widely used in industry be cause of their properties. The study of the production and properties of metals is known as metallurgy.
The separation between the atoms in metals is small, so most metals are dense. The atoms are arranged regu larly and can slide over each other. That is why metals are malleable (can be deformed and bent without frac ture) and ductile (can be drawn into wire). Metals vary greatly in their properties. For example, lead is soft and can be bent by hand, while iron can only be worked by hammering at red heat.
The regular arrangement of atoms in metals gives them a crystalline structure. Irregular crystals are called grains. The properties of the metals depend on the size, shape, orientation, and composition of these grains. In general, a metal with small grains will be harder and stronger than one with coarse grains.
Heat treatment such as quenching, tempering, or annealing controls the nature of the grains and their size in the metal. Small amounts of other metals (less than 1 per cent) are often added to a pure metal. This is called alloying (легирование) and it changes the grain struc ture and properties of metals.
All metals can be formed by drawing, rolling, ham mering and extrusion, but some require hot-working. Metals are subject to metal fatigue and to creep (the slow increase in length under stress) causing deformation and failure. Both effects are taken into account by engineers when designing, for example, airplanes, gas-turbines, and pressure vessels for high-temperature chemical proc esses. Metals can be worked using machine-tools such as lathe, milling machine, shaper and grinder.
The ways of working a metal depend on its properties. Many metals can be melted and cast in moulds, but spe cial conditions are required for metals that react with air.
Vocabulary:
property — свойство
metallurgy — металлургия
separation — разделение, отстояние
dense — плотный
arrangement — расположение
regularly — регулярно, правильно
to slide — скользить
malleable — ковкий, податливый, способ ный деформироваться
bent pp of bend — гнуть
to fracture — ломать
ductile — эластичный, ковкий
to draw — волочить, тянуть
wire — проволока
lead — свинец
iron — железо, чугун
grain — зерно
to depend — зависеть
size — размер, величина
shape — форма, формировать
composition — состав
coarse — грубый, крупный
treatment — обработка
quenching — закалка
tempering — отпуск после закалки, нор мализация
annealing — отжиг, отпуск
rolling — прокатка
to hammer — ковать (напр. молотом)
extrusion — экструзия
metal fatigue — усталость металла
creep — ползучесть
stress — давление,
failure — повреждение, разрушение
vessel — сосуд, котел, судно
lathe — токарный станок
milling machine — фрезерный станок
shaper — строгальный станок
grinder — шлифовальный станок
to melt — плавить, плавиться расплавить
to cast — отливать, отлить
mould — форма (для отливки)
General understanding:
1. What are metals and what do we call metallurgy?
2. Why are most metals dense?
3. Why are metals malleable?
4. What is malleability?
5. What are grains?
6. What is alloying?
7. What is crystalline structure?
8. What do the properties of metals depend on?
9. What changes the size of grains in metals?
10. What are the main processes of metal forming?
11. How are metals worked?
12. What is creeping?
Exercise 2.1. Find the following words and word combinations in the text:
1. Свойства металлов
2. расстояние между атомами
3. правильное расположение
4. сильно отличаются по своим свойствам
5. кристаллическая структура
14. структура и свойства зерна
15. горячая обработка
16. усталость металла
17. ползучесть металла
18. плавка и отливка в формы
19. способы обработки металла
Exercise 2.2. Complete the following sentences:
2. Metallurgy is.
3. Most metals are.
4. The regular arrangement of atoms in metals.
5. Irregular crystals.
6. The properties of the metals depend.
7. Metals with small grains will be.
8. . controls the nature of the grains in the metal.
10. All metals can be formed by.
12. Metals can be worked using.
Exercise 2.3. Translate into English:
1. Металлы — плотные материалы потому, что между атомами в металлах малое расстояние.
2. Металлы имеют кристаллическую структуру из-за правильного расположения атомов.
The most important metal in industry is iron and its alloy — steel. Steel is an alloy of iron and carbon. It is strong and stiff, but corrodes easily through rusting, although stainless and other special steels resist corro sion. The amount of carbon in a steel influences its prop erties considerably. Steels of low carbon content (mild steels) are quite ductile and are used in the manufacture of sheet iron, wire, and pipes. Medium-carbon steels con taining from 0.2 to 0.4 per cent carbon are tougher and stronger and are used as structural steels. Both mild and medium-carbon steels are suitable for forging and weld ing. High-carbon steels contain from 0.4 to 1.5 per cent carbon, are hard and brittle and are used in cutting tools, surgical instruments, razor blades and springs. Tool steel, also called silver steel, contains about 1 per cent carbon and is strengthened and toughened by quenching and tempering.
The inclusion of other elements affects the properties of the steel. Manganese gives extra strength and tough ness. Steel containing 4 per cent silicon is used for trans former cores or electromagnets because it has large grains acting like small magnets. The addition of chro mium gives extra strength and corrosion resistance, so we can get rust-proof steels. Heating in the presence of carbon or nitrogen-rich materials is used to form a hard surface on steel (case-hardening). High-speed steels, which are extremely important in machine-tools, contain chromium and tungsten plus smaller amounts of vana dium, molybdenum and other metals.
Vocabulary:
alloy — сплав
carbon— углерод
stiff — жесткий
to corrode — разъедать, ржаветь
rusty — ржавый
stainless — нержавеющий
to resist — сопротивляться
considerably — значительно, гораздо
tough — крепкий, жесткий, прочный, вынос ливый
forging — ковка
welding — сварка
brittle — хрупкий, ломкий
cutting tools — режущие инструменты
surgical instruments — хирургические ин струменты
blade — лезвие
spring — пружина
inclusion — включение
to affect — влиять
manganese — марганец
silicon — кремний
rust-proof — нержавеющий
nitrogen — азот
tungsten — вольфрам
General understanding:
1. What is steel?
2. What are the main properties of steel?
3. What are the drawbacks of steel?
4. What kinds of steel do you know? Where are they used?
5. What gives the addition of manganese, silicon and chromium to steel?
6. What can be made of mild steels (medium-carbon steels, high-carbon steels)?
7. What kind of steels can be forged and welded?
8. How can we get rust-proof (stainless) steel?
9. What is used to form a hard surface on steel?
10. What are high-speed steels alloyed with?
Exercise 2.4. Find the following words and word combinations in the text:
1. сплав железа и углерода
2. прочный и жесткий
3. легко коррозирует
4. нержавеющая сталь
5. низкое содержание углерода
7. листовое железо, проволока, трубы
8. конструкционные стали
9. пригодны для ковки и сварки
10. твердый и хрупкий
11. режущие инструменты
12. хирургические инструменты
13. инструментальная сталь
15. добавление марганца (кремния, хрома, вольфра ма, молибдена, ванадия)
Text С: METHODS OF STEEL HEAT TREATMENT
Quenching is a heat treatment when metal at a high temperature is rapidly cooled by immersion in water or oil. Quenching makes steel harder and more brittle, with small grains structure.
Tempering is a heat treatment applied to steel and certain alloys. Hardened steel after quenching from a high temperature is too hard and brittle for many appli cations and is also brittle. Tempering, that is re-heating to an intermediate temperature and cooling slowly, re duces this hardness and brittleness. Tempering tempera tures depend on the composition of the steel but are fre quently between 100 and 650 °C. Higher temperatures usually give
Annealing is a heat treatment in which a material at high temperature is cooled slowly. After cooling the metal again becomes malleable and ductile (capable of being bent many times without cracking).
All these methods of steel heat treatment are used to obtain steels with certain mechanical properties for cer tain needs.
Vocabulary:
to immerse — погружать
to apply — применять
intermediate — промежуточный
oxide film — оксидная пленка
annealing — отжиг, отпуск
cracking — растрескивание
General understanding:
1. What can be done to obtain harder steel?
2. What makes steel more soft and tough?
3. What makes steel more malleable and ductile?
4. What can serve as the indicator of metal tempera ture while heating it?
5. What temperature range is used for tempering?
6. What are the methods of steel heat treatment used for?
Exercise 2.5. Translate into English the following words and word combinations:
1. температура нормализации
2. мелкозернистая структура
3. быстрое охлаждение
4. закаленная сталь
6. окисная пленка
7. индикатор температуры
8. медленное охлаждение
UNIT 3
METALWORKING
Text A: METALWORKING PROCESSES: ROLLING, EXTRUSION.
Text B: DRAWING, FORGING, SHEET METAL FORMING.
Text C: METALWORKING AND METAL PROPRTIES.
Text A: METALWORKING PROCESSES
Metals are important in industry because they can be easily deformed into useful shapes. A lot of metalworking processes have been developed for certain applica tions. They can be divided into five broad groups:
2. extrusion,
5. sheet-metal forming.
During the first four processes metal is subjected to large amounts of strain (deformation). But if deformation goes at a high temperature, the metal will recrystallize — that is, new strain-free grains will grow instead of deformed grains. For this reason metals are usually rolled, ex truded, drawn, or forged above their recrystallization temperature. This is called hot working. Under these conditions there is no limit to the compressive plastic strain to which the metal can be subjected.
Other processes are performed below the recrystalli zation temperature. These are called cold working. Cold working hardens metal and makes the part stronger. However, there is a limit to the strain before a cold part cracks.
Rolling is the most common metalworking process. More than 90 percent of the aluminum, steel and copper produced is rolled at least once in the course of produc tion. The most common rolled product is sheet. Rolling can be done either hot or cold. If the rolling is finished cold, the surface will be smoother and the product stronger.
Extrusion is pushing the billet to flow through the orifice of a die. Products may have either a simple or a complex cross section. Aluminum window frames are the examples of complex extrusions.
Tubes or other hollow parts can also be extruded. The initial piece is a thick-walled tube, and the extruded part is shaped between a die on the outside of the tube and a mandrel held on the inside.
In impact extrusion (also called back-extrusion) (штамповка выдавливанием), the workpiece is placed in the bottom of a hole and a loosely fitting ram is pushed against it. The ram forces the metal to flow back around it, with the gap between the ram and the die determin ing the wall thickness. The example of this process is the manufacturing of aluminum beer cans.
Vocabulary:
useful — полезный
shape — форма, формировать
rolling — прокатка
extrusion — экструзия, выдавливание
drawing — волочение
forging — ковка
sheet — лист
to subject — подвергать
amount — количество
condition — состояние, условие
perform — выполнять, проводить
to harden — делаться твердым, упрочняться
at least — по крайней мере
common — общий
billet — заготовка, болванка
orifice — отверстие
die — штамп, пуансон, матрица, фильера, во лочильная доска
cross section — поперечное сечение
window frame — рама окна
tube — труба
hollow — полый
initial — первоначальный, начальный
thick-walled — толстостенный
mandrel — оправка, сердечник
impact — удар
loosely — свободно, с зазором
fitting — зд. посадка
ram — пуансон, плунжер
force — сила
gap — промежуток, зазор
to determine — устанавливать, опреде лять
General understanding:
1. Why are metals so important in industry?
2. What are the main metalworking processes?
3. Why are metals worked mostly hot?
4. What properties does cold working give to metals?
5. What is rolling? Where is it used?
6. What is extrusion? What shapes can be obtained after extrusion?
7. What are the types of extrusion?
Exercise 3.1. Find the following in the text:
1. могут легко деформироваться
3. подвергать большим деформациям
4. зерна свободные от деформации
5. температура перекристаллизации
6. пластическая деформация сжатия
7. самый обычный процесс обработки металла
8. самое обычное изделие проката
9. отверстие фильеры
11. сложное сечение
12. пустотелые детали
13. свободно входящий плунжер
14. зазор между плунжером (пуансоном) и штампом
15. толщина стенки
Exercise 3.2. Translate into English:
1. Способность металла перекристаллизовываться при высокой температуре используется при горячей обработке.
2. Перекристаллизация — это рост новых, свобод ных от деформации зерен.
3. Во время горячей обработки металл может под вергаться очень большой пластической деформации сжатия.
4. Холодная обработка делает металл тверже и прочнее, но некоторые металлы имеют предел дефор мации.
5. Листовой прокат может производиться горячим или холодным.
6. Поверхность холоднокатаного листа более глад кая и он прочнее.
7. Поперечное сечение фильеры для экструзии мо жет быть простым или сложным.
8. Алюминиевые и медные сплавы являются наи лучшими для экструзии из-за их пластичности при деформации.
9. Алюминиевые банки, тюбики для зубной пасты являются примерами использования штамповки вы давливанием.
10. Толщина стенки алюминиевой банки определя ется зазором между пунсоном и штампом.
Text В: DRAWING
Drawing consists of pulling metal through a die. One type is wire drawing. The diameter reduction that can be achieved in one die is limited, but several dies in se ries can be used to get the desired reduction.
Sheet metal forming
Sheet metal forming (штамповка листового металла) is widely used when parts of certain shape and size are needed. It includes forging, bending and shearing. One characteristic of sheet metal forming is that the thick ness of the sheet changes little in processing. The metal is stretched just beyond its yield point (2 to 4 percent strain) in order to retain the new shape. Bending can be done by pressing between two dies. Shearing is a cutting operation similar to that used for cloth.
Each of these processes may be used alone, but often all three are used on one part. For example, to make the roof of an automobile from a flat sheet, the edges are gripped and the piece pulled in tension over a lower die. Next an upper die is pressed over the top, finishing the forming operation (штамповку), and finally the edges are sheared off to give the final dimensions.
Forging is the shaping of a piece of metal by pushing with open or closed dies. It is usually done hot in order to reduce the required force and increase the metal's plas ticity.
Open-die forging is usually done by hammering a part between two flat faces. It is used to make parts that are too big to be formed in a closed die or in cases where only a few parts are to be made. The earliest forging machines lifted a large hammer that was then dropped on the workpiece, but now air or steam hammers are used, since they allow greater control over the force and the rate of forming. The part is shaped by moving or turning it be tween blows.
Closed-die forging is the shaping of hot metal within the walls of two dies that come together to enclose the workpiece on all sides. The process starts with a rod or bar cut to the length needed to fill the die. Since large, complex shapes and large strains are involved, several dies may be used to go from the initial bar to the final shape. With closed dies, parts can be made to close toler ances so that little finish machining is required.
Two closed-die forging operations are given special names. They are upsetting and coining. Coining takes its name from the final stage of forming metal coins, where the desired imprint is formed on a metal disk that is pressed in a closed die. Coining involves small strains and is done cold. Upsetting involves a flow of the metal back upon itself. An example of this process is the push ing of a short length of a rod through a hole, clamping the rod, and then hitting the exposed length with a die to form the head of a nail or bolt.
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