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English language for technical colleges

2. What are the best properties of fibre-glass?

3. What do composite material usually consist of?

4. What is used as matrix in composites?

5. What is used as filler or fibers in composites?

6. How are the composite materials with ceramic and metal matrices called?

7. What are the advantages of composites?

8. What are the disadvantages of composites?

9. Why anisotropic properties of composites should be taken into account?

Exercise 5.5. Find equivalents in the text:

1. композитные материалы

2. уникальные механические качества

3. полимерные матричные композиты

4. составлять 60% объема

5. углепластик

6. привлекательные качества

7. структура, подвергающаяся воздействию разнонаправленных сил

Exercise 5.6. Translate into Russian:

1. PMC is fabricated so that all the fibres are lined up parallel to one another.

2. Forming strong connections between separate composite material components is difficult.

3. Fabricating composite materials is a complex process.

4. Composite materials have certain advantages over conventional materials

5. Nowadays, composites are being used for structures such as bridges, boat-building etc.

6. Continuous-fibre composites are generally required for structural applications.


FAMOUS INVENTORS

Alfred Bernhard Nobel was a famous Swedish chemist and inventor. He was born in Stockholm in 1833. After receiving an education in St. Petersburg, Russia, and then in the United States, where he studied mechanical engineering, he returned to St. Petersburg to work with his father in Russia. They were developing mines, torpedoes, and other explosives.

In a family-owned factory in Heleneborg, Sweden, he developed a safe way to handle nitroglycerine, after a factory explosion in 1864 killed his younger brother and four other people. In 1867 Nobel achieved his goal: he produced what he called dynamite динамит. Не later produced one of the first smokeless powders (порох). At the time of his death he controlled factories for the manufacture of explosives (взрывчатое вещество) in many parts of the world. In his will he wanted that the major portion of his money left became a fund for yearly prizes in his name. The prizes were to be given for merits (заслуги) in physics, chemistry, medicine and physiology, literature, and world peace. A prize in economics has been awarded since 1969.


UNIT 6

WELDING

I. Text A: «Welding», Text В: «Other types of welding»

II. Famous People of Science and Technology: James Prescott Joule.

 

Text A: «WELDING»


Welding is a process when metal parts are joined together by the application of heat, pressure, or a combination of both. The processes of welding can be divided into two main groups:

• pressure welding, when the weld is achieved by pressure and

• heat welding, when the weld is achieved by heat. Heat welding is the most common welding process used today.

Nowadays welding is used instead of bolting and riveting in the construction of many types of structures, including bridges, buildings, and ships. It is also a basic process in the manufacture of machinery and in the motor and aircraft industries. It is necessary almost in all productions where metals are used.

The welding process depends greatly on the properties of the metals, the purpose of their application and the available equipment. Welding processes are classified according to the sources of heat and pressure used.

The welding processes widely employed today include gas welding, arc welding, and resistance welding. Other joining processes are laser welding, and electron-beam welding.

Gas Welding

Gas welding is a non-pressure process using heat from a gas flame. The flame is applied directly to the metal edges to be joined and simultaneously to a filler metal in the form of wire or rod, called the welding rod, which is melted to the joint. Gas welding has the advantage of using equipment that is portable and does not require an electric power source. The surfaces to be welded and the welding rod are coated with flux, a fusible material that shields the material from air, which would result in a defective weld.

Arc Welding

Arc-welding is the most important welding process for joining steels. It requires a continuous supply of either direct or alternating electrical current. This current is used to create an electric arc, which generates enough heat to melt metal and create a weld.

Arc welding has several advantages over other welding methods. Arc welding is faster because the concentration of heat is high. Also, fluxes are not necessary in certain methods of arc welding. The most widely used arc-welding processes are shielded metal arc, gas-tungsten arc, gas-metal arc, and submerged arc.

Shielded Metal Arc

In shielded metal-arc welding, a metallic electrode, which conducts electricity, is coated with flux and connected to a source of electric current. The metal to be welded is connected to the other end of the same source of current. An electric arc is formed by touching the tip of the electrode to the metal and then drawing it away. The intense heat of the arc melts both parts to be welded and the point of the metal electrode, which supplies filler metal for the weld. This process is used mainly for welding steels.

Vocabulary:

to join — соединять

pressure welding — сварка давлением

heat welding — сварка нагреванием

instead — вместо, взамен

bolting — скрепление болтами

riveting — клепка

basic — основной

to manufacture — изготовлять

to depend — зависеть от

purpose — цель

available — имеющийся в наличии

equipment — оборудование

source — источник

gas welding — газосварка

arc welding — электродуговая сварка

resistance welding — контактная сварка

laser welding — лазерная сварка

electron-beam welding — электронно-лучевая сварка

flame — пламя

edge — край

simultaneously — одновременно

filler — наполнитель

wire — проволока

rod — прут, стержень

to melt — плавить(ся)

joint — соединение, стык

advantage — преимущество

to require — требовать нуждаться

surface — поверхность

coated — покрытый

flux — флюс

fusible — плавкий

to shield — заслонять, защищать

touching — касание

tip — кончик

General understanding:

1. How can a process of welding be defined?

2. What are the two main groups of processes of welding?

3. How can we join metal parts together?

4. What is welding used for nowadays?

5. Where is welding necessary?

6. What do the welding processes of today include?

7. What are the principles of gas welding?

8. What kinds of welding can be used for joining steels?

9. What does arc welding require? 10. What is the difference between the arc welding and shielded-metal welding?

Exercise 6.1. Find the following words and word combinations in the text:

1. сварка давлением

2. тепловая сварка

3. болтовое (клепаное) соединение

4. процесс сварки

5. зависеть от свойств металлов

6. имеющееся оборудование

7. сварочный электрод

8. плавкий материал

9. дефектный сварной шов

10. непрерывная подача электрического тока

11. электрическая дуга

12. источник электрического тока

 

Text В: «OTHER TYPES OF WELDING»

Non-consumable Electrode Arc welding

As a non-consumable electrodes tungsten or carbon electrodes can be used. In gas-tungsten arc welding a tungsten electrode is used in place of the metal electrode used in shielded metal-arc welding. A chemically inert gas, such as argon, helium, or carbon dioxide is used to shield the metal from oxidation. The heat from the arc formed between the electrode and the metal melts the edges of the metal. Metal for the weld may be added by placing a bare wire in the arc or the point of the weld. This process can be used with nearly all metals and produces a high-quality weld. However, the rate of welding is considerably slower than in other processes.

Gas-Metal Arc

In gas-metal welding, a bare electrode is shielded from the air by surrounding it with argon or carbon dioxide gas and sometimes by coating the electrode with flux. The electrode is fed into the electric arc, and melts off in droplets that enter the liquid metal of the weld seam. Most metals can be joined by this process.

Submerged Arc

Submerged-arc welding is similar to gas-metal arc welding, but in this process no gas is used to shield the weld. Instead of that, the arc and tip of the wire are submerged beneath a layer of granular, fusible material that covers the weld seam. This process is also called electroslag welding. It is very efficient but can be used only with steels.

Resistance Welding

In resistance welding, heat is obtained from the resistance of metal to the flow of an electric current. Electrodes are clamped on each side of the parts to be welded, the parts are subjected to great pressure, and a heavy current is applied for a short period of time. The point where the two metals touch creates resistance to the flow of current. This resistance causes heat, which melts the metals and creates the weld. Resistance welding is widely employed in many fields of sheet metal or wire manufacturing and is often used for welds made by automatic or semi-automatic machines especially in automobile industry.

Vocabulary

gas-tungsten — сварка оплавлением вольфрамовым электродом в среде инертного газа

inert — инертный

edge — край

bare — голый

rate — зд. скорость

gas-metal arc — аргонодуговая сварка

considerably — значительно, гораздо

surrounding — окружающий

carbon dioxide — углекислый газ

droplet — капелька

liquid — жидкость, жидкий

beneath — под, ниже, внизу

layer — слой

weld seam — сварной шов

resistance — сопротивление

clamp — зажим, зажимать

sheet — лист

fusible — плавкий

granular — плавкий

semi-automatic — полуавтоматическая

to create — создавать

to submerge — погружать

General understanding:

1. What is the difference between the arc-welding and non-consumable electrode arc welding?

2. What are the disadvantages of the non-consumable electrode arc welding?

3. How is electrode protected from the air in gas-metal arc welding?

4. What is submerged arc welding?

5. What is the principle of resistance welding?

6. Where is semi-automatic welding employed?

Exercise 6.2. Translate into English:

1. вольфрамовый электрод

2. инертный газ

3. окисление

4. высококачественный сварочный шов

5. скорость сварки

6. аргон, гелий, углекислый газ

7. жидкий металл

8. слой плавкого материала в виде гранул

9. листовой металл

10. полувтоматические сварочные станки

Exercise 6.3. Translate into Russian:

1. In resistance welding, heat is obtained from the resistance of metal to the flow of an electric current.

2. The heat from the arc melts the edges of the metal.

3. A bare electrode is shielded from the air by surrounding it with argon or carbon dioxide gas.

4. Submerged-arc welding is similar to gas-metal arc welding.

5. Electrodes are clamped on each side of the parts to be welded.

6. Resistance causes heat which melts the metals and creates the weld.

FAMOUS PEOPLE OF SCIENCE AND TECHNOLOGY

James Prescott Joule, famous British physicist, was born in 1818 in Salford, England.

Joule was one of the most outstanding physicists of his time. He is best known for his research in electricity and thermodynamics. In the course of his investigations of the heat emitted in an electrical circuit, he formulated the law, now known as Joule's law of electric heating. This law states that the amount of heat produced each second in a conductor by electric current is proportional to the resistance of the conductor and to the square of the current. Joule experimentally verified the law of conservation of energy in his study of the conversion of mechanical energy into heat energy.

Joule determined the numerical relation between heat and mechanical energy, or the mechanical equivalent of heat, using many independent methods. The unit of energy, called the joule, is named after him. It is equal to 1 watt-second. Together with the physicist William Thomson (Baron Kelvin), Joule found that the temperature of a gas falls when it expands without doing any work. This phenomenon, which became known as the Joule-Thomson effect, lies in the operation of modern refrigeration and air-conditioning systems.

 


UNIT 7

AUTOMATION AND ROBOTICS

I. Text A: «Automation», Text B: «Types of automation»,

Text C: «Robots In manufacturing»

II. Famous people of science and technology: James Watt.

 

Text A: «AUTOMATION»


Automation is the system of manufacture performing certain tasks, previously done by people, by machines only. The sequences of operations are controlled automatically. The most familiar example of a highly automated system is an assembly plant for automobiles or other complex products.

The term automation is also used to describe non-manufacturing systems in which automatic devices can operate independently of human control. Such devices as automatic pilots, automatic telephone equipment and automated control systems are used to perform various operations much faster and better than could be done by people.

Automated manufacturing had several steps in its development. Mechanization was the first step necessary in the development of automation. The simplification of work made it possible to design and build machines that resembled the motions of the worker. These specialized machines were motorized and they had better production efficiency.

Industrial robots, originally designed only to perform simple tasks in environments dangerous to human workers, are now widely used to transfer, manipulate, and position both light and heavy workpieces performing all the functions of a transfer machine.

In the 1920s the automobile industry for the first time used an integrated system of production. This method of production was adopted by most car manufacturers and became known as Detroit automation.

The feedback principle is used in all automatic-control mechanisms when machines have ability to correct themselves. The feedback principle has been used for centuries. An outstanding early example is the flyball governor, invented in 1788 by James Watt to control the speed of the steam engine. The common household thermostat is another example of a feedback device.

Using feedback devices, machines can start, stop, speed up, slow down, count, inspect, test, compare, and measure. These operations are commonly applied to a wide variety of production operations.

Computers have greatly facilitated the use of feedback in manufacturing processes. Computers gave rise to the development of numerically controlled machines. The motions of these machines are controlled by punched paper or magnetic tapes. In numerically controlled machining centres machine tools can perform several different machining operations.

More recently, the introduction of microprocessors and computers have made possible the development of computer-aided design and computer-aided manufacture (CAD and CAM) technologies. When using these systems a designer draws a part and indicates its dimensions with the help of a mouse, light pen, or other input device. After the drawing has been completed the computer automatically gives the instructions that direct a machining centre to machine the part.

Another development using automation are the flexible manufacturing systems (FMS). A computer in FMS can be used to monitor and control the operation of the whole factory.

Automation has also had an influence on the areas of the economy other than manufacturing. Small computers are used in systems called word processors, which are rapidly becoming a standard part of the modern office. They are used to edit texts, to type letters and so on.

Automation in Industry

Many industries are highly automated or use automation technology in some part of their operation. In communications and especially in the telephone industry dialing and transmission are all done automatically. Railways are also controlled by automatic signaling devices, which have sensors that detect carriages passing a particular point. In this way the movement and location of trains can be monitored.

Not all industries require the same degree of automation. Sales, agriculture, and some service industries are difficult to automate, though agriculture industry may become more mechanized, especially in the processing and packaging of foods.

The automation technology in manufacturing and assembly is widely used in car and other consumer product industries.

Nevertheless, each industry has its own concept of automation that answers its particular production needs.

Vocabulary:

automation — автоматизация

previously — ранее

sequence — последовательность

assembly plant — сборочный завод

non-manufacturing — непроизводственный

device — устройство, прибор

resemble — походить

efficiency — эффективность

flyball governor — центробежный регулятор

steam engine — паровоз

household thermostat — бытовой термостат

facilitate — способствовать

punched — перфорированный

aid — помощь

dimension — измерение, размеры

General understanding:

1. How is the term automation defined in the text?

2. What is the most «familiar example» of automation given in the text?

3. What was the first step in the development of automaton?

4. What were the first robots originally designed for?

5. What was the first industry to adopt the new integrated system of production?

6. What is feedback principle?

7. What do the abbreviations CAM and CAD stand for?

8. What is FMS?

9. What industries use automation technologies?

Exercise 7.1. Find the following words and word combinations in the text:

1. автоматические устройства

2. автоматизированное производство

3. выполнять простые задачи

4. как легкие, так и тяжелые детали

5. интегрированная система производства

6. принцип обратной связи

7. механизм может разгоняться и тормозить

8. компьютер автоматически посылает команды

9. высокоавтоматизированная система

10. непроизводственная система

 

Text В: «TYPES OF AUTOMATION»

Applications of Automation and Robotics in Industry

Manufacturing is one of the most important application area for automation technology. There are several types of automation in manufacturing. The examples of automated systems used in manufacturing are described below.

1. Fixed automation, sometimes called «hard automation» refers to automated machines in which the equipment configuration allows fixed sequence of processing operations. These machines are programmed by their design to make only certain processing operations. They are not easily changed over from one product style to another. This form of automation needs high initial investments and high production rates. That is why it is suitable for products that are made in large volumes. Examples of fixed automation are machining transfer lines found in the automobile industry, automatic assembly machines and certain chemical processes.

2. Programmable automation is a form of automation for producing products in large quantities, ranging from several dozen to several thousand units at a time. For each new product the production equipment must be reprogrammed and changed over. This reprogramming and changeover take a period of non-productive time. Production rates in programmable automation are generally lower than in fixed automation, because the equipment is designed to facilitate product changeover rather than for product specialization. A numerical-control machine-tool is a good example of programmable automation. The program is coded in computer memory for each different product style and the machine-tool is controlled by the computer programme.

3. Flexible automation is a kind of programmable automation. Programmable automation requires time to re-program and change over the production equipment for each series of new product. This is lost production time, which is expensive. In flexible automation the number of products is limited so that the changeover of the equipment can be done very quickly and automatically. The reprogramming of the equipment in flexible automation is done at a computer terminal without using the production equipment itself. Flexible automation allows a mixture of different products to be produced one right after another.

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