Тесты для инженеров -механиков на тему Станки и др

«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?

Task 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.

«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 - аргоно-дуговая сварка

considerably - значительно, гораздо

surounding - 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 - зернистый

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?

Task 1. 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.

Task 2. 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.

«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 nonmanufacturing 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 centers 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 is 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 dialling and transmission are all done automatically. Rail­ways are also controlled by automatic signalling 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

nonmanufacturing - 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?

Task 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.

«TYPES OF AUTOMATION»

Applications of Automation and Robotics in Industry

Manufacturing is one of the most important applica­tion areas 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.

Vocabulary:

equipment - оборудование

sequence- последовательность

initial - первоначальный, начальный

investment - инвестиция, вклад

to facilitate - способствовать

rate - скорость, темп

assembly machines - сборочные машины

quantity - количество

non-productive - непроизводительный

changeover - переход, переналадка

General understanding:

1. What is the most important application of automation?

2. What are the types of automation used in manu­facturing?

3. What is fixed automation?

4. What are the limitations of hard automation?

5. What is the best example of programmable auto­mation?

6. What are the limitations of programmable automa­tion?

7. What are the advantages of flexible automation?

8. Is it possible to produce different products one after another using automation technology?

Task 1. Find equivalents in English in the text:

1. сфера применения;

2. фиксированная последовательность операций;

3. автоматические сборочные машины;

4. определенные химические процессы;

5. станок с числовым программным управлением;

6. потерянное производственное время;

7. разнообразная продукция.

Task 2. Explain in English what does the following mean:

1. automation technology;

2. fixed automation;

3. assembly machines;

4. non-productive time;

5. programmable automation;

6. computer terminal;

7. numerical-control machine-tool.

«ROBOTS IN MANUFACTURING»

Today most robots are used in manufacturing opera­tions. The applications of robots can be divided into three categories:

1. material handling

2. processing operations

3. assembly and inspection.

Material-handling is the transfer of material and load­ing and unloading of machines. Material-transfer appli­cations require the robot to move materials or work parts from one to another. Many of these tasks are relatively simple: robots pick up parts from one conveyor and place them on another. Other transfer operations are more complex, such as placing parts in an arrangement that can be calculated by the robot. Machine loading and unloading operations utilize a robot to load and unload parts. This requires the robot to be equipped with a gripper that can grasp parts. Usually the gripper must be designed specifically for the particular part geometry.

In robotic processing operations, the robot manipu­lates a tool to perform a process on the work part. Exam­ples of such applications include spot welding, continu­ous arc welding and spray painting. Spot welding of automobile bodies is one of the most common applications of industrial robots. The robot positions a spot welder against the automobile panels and frames to join them. Arc welding is a continuous process in which robot moves the welding rod along the welding seam. Spray painting is the manipulation of a spray-painting gun over the surface of the object to be coated. Other operations in this category include grinding and polishing in which a rotating spindle serves as the robot's tool.

The third application area of industrial robots is as­sembly and inspection. The use of robots in assembly is expected to increase because of the high cost of manual labour. But the design of the product is an important aspect of robotic assembly. Assembly methods that are satisfactory for humans are not always suitable for ro­bots. Screws and nuts are widely used for fastening in manual assembly, but the same operations are extremely difficult for a one-armed robot.

Inspection is another area of factory operations in which the utilization of robots is growing. In a typical inspection job, the robot positions a sensor with respect to the work part and determines whether the part answers the quality specifications. In nearly all industrial robotic applications, the robot provides a substitute for human labour. There are certain characteristics of industrial jobs performed by humans that can be done by robots:

1. the operation is repetitive, involving the same basic work motions every cycle,

2. the operation is hazardous or uncomfortable for the human worker (for example: spray painting, spot welding, arc welding, and certain machine loading and unloading tasks),

3. the workpiece or tool are too heavy and difficult to handle,

4. the operation allows the robot to be used on two or three shifts.

Vocabulary:

handling - обращение

transfer - передача, перенос

location - местонахождение

pick up - брать, подбирать

arrangement - расположение

to utilize - утилизировать, находить при­менение

gripper - захват

to grasp - схватывать

spot welding - точечная сварка

continuous - непрерывный

arc welding - электродуговая сварка

spray painting - окраска распылением

frame - рама

spray-painting gun - распылитель краски

grinding - шлифование

polishing - полирование

spindle - шпиндель

manual - ручной

labour - труд

hazardous - опасный

shift - смена

General understanding:

1. How are robots used in manufacturing?

2. What is "material handling"?

3. What does a robot need to be equipped with to do loading and unloading operations?

4. What does robot manipulate in robotic processing operation?

5. What is the most common application of robots in automobile manufacturing?

6. What operations could be done by robot in car manufacturing industry?

7. What are the main reasons to use robots in produc­tion?

8. How can robots inspect the quality of production?

9. What operations could be done by robots in hazard­ous or uncomfortable for the human workers conditions?

Task 1. Translate into English.

1. Существует несколько различных сфер использования автоматизации в производстве.

2. Для использования жесткой автоматизации не­обходимы большие инвестиции.

3. Жесткая автоматизация широко используется в химической промышленности.

4. Станки с числовым программным управлением - хороший пример программируемой автоматизации.

5. Гибкая автоматизация делает возможным пере­программирование оборудования.

6. Время простоя оборудования оборачивается боль­шими убытками.

7. Использование гибкой автоматизации делает воз­можным проиводство разнообразной продукции.

«MACHINE-TOOLS»

Machine-tools are used to shape metals and other ma­terials. The material to be shaped is called the workpiece. Most machine-tools are now electrically driven. Machine-tools with electrical drive are faster and more accurate than hand tools: they were an important element in the development of mass-production processes, as they allowed individual parts to be made in large numbers so as to be interchangeable.

All machine-tools have facilities for holding both the workpiece and the tool, and for accurately controlling the movement of the cutting tool relative to the workpiece. Most machining operations generate large amounts of heat, and use cooling fluids (usually a mixture of water and oils) for cooling and lubrication.

Machine-tools usually work materials mechanically but other machining methods have been developed lately.

They include chemical machining, spark erosion to machine very hard materials to any shape by means of a continuous high-voltage spark (discharge) between an electrode and a workpiece. Other machining methods include drilling using ultrasound, and cutting by means of a laser beam. Numerical control of machine-tools and flexible manufacturing systems have made it possible for complete systems of machine-tools to be used flexibly for the manufacture of a range of products.

Vocabulary:

machine-tools - станки

electrically driven - с электроприводом

shape - форма

workpiece - деталь

accurate - точный

development - развитие

to allow - позволять, разрешать

interchangeable- взаимозаменяемый

facility - приспособление

relative - относительный

amount - количество

fluid - жидкость

to lubricate - смазывать

spark erosion - электроискровая об­работка

discharge - разряд

by means of - посредством

beam - луч

drilling - сверление

flexible - гибкий

range - ассортимент, диапазон

General understanding:

1. What are machine-tools used for?

2. How are most machine-tools driven nowadays?

3. What facilities have all machine-tools?

4. How are the cutting tool and the workpiece cooled during machining?

5. What other machining methods have been devel­oped lately?

6. What systems are used now for the manufacture of a range of products without the use of manual labour?

Task 1. Find English equivalents in the text:

1. обрабатываемый материал;

2. электропривод;

3. более точный;

4. отдельные детали;

5. процесс массового производства;

6. приспособления для держания резца и детали;

7. операции по механической обработке детали;

8. высоковольтный разряд;

9. сверление ультразвуком;

10. резание с помощью лазерного луча;

11. гибкие производственные системы;

12. детали круглого сечения;

13. поворачивать деталь вокруг ее оси;

14. двигать в сторону, двигать по направлению к детали;

15. глубина резания;

16. непрерывное вращение детали;

17. движение резца вдоль станины.

Task 2. Translate into English.

1. Токарный станок позволяет производить детали круглого сечения.

2. Деталь зажимается в патроне или на планшайбе токарного станка.

3. Резец может двигаться как вдоль станины, так и под прямым углом к ней.

4. Современные токарные станки часто имеют циф­ровое управление.

«LATHE»

Lathe is still the most important machine-tool. It pro­duces parts of circular cross-section by turning the workpiece on its axis and cutting its surface with a sharp stationary tool. The tool may be moved sideways to pro­duce a cylindrical part and moved towards the workpiece to control the depth of cut. Nowadays all lathes are power-driven by electric motors. That allows continuous rotation of the workpiece at a variety of speeds. The modern lathe is driven by means of a headstock supporting a hollow spindle on accurate bearings and carrying either a chuck or a faceplate, to which the workpiece is clamped. The movement of the tool, both along the lathe bed and at right angle to it, can be accurately controlled, so ena­bling a part to be machined to close tolerances. Modern lathes are often under numerical control.

Vocabulary:

lathe - токарный станок

circular cross-section - круглое попереч­ное сечение

surface - поверхность

stationary - неподвижный, стационар­ный

sideways - в сторону

variety - разнообразие, разновидность

depth - глубина

headstock - передняя бабка

spindle - шпиндель

chuck - зажим, патрон

faceplate - планшайба

lathe bed - станина станка

to enable - давать возможность

tolerance - допуск

General understanding:

1. What are machine-tools used for?

2. How are most machine-tools driven nowadays?

3. What facilities have all machine-tools?

4. How are the cutting tool and the workpiece cooled during machining?

5. What other machining methods have been devel­oped lately?

6. What systems are used now for the manufacture of a range of products without the use of manual labour?

7. What parts can be made with lathes?

8. How can the cutting tool be moved on a lathe?

9. How is the workpiece clamped in a lathe?

10. Can we change the speeds of workpiece rotation in a lathe?

11.What is numerical control of machine tools used for?

Task 1. Find English equivalents in the text:

1.обрабатываемый материал;

2.электропривод;

3.более точный;

4.отдельные детали;

5.процесс массового производства;

6.приспособления для держания резца и детали;

7.операции по механической обработке детали;

8.высоковольтный разряд;

9.сверление ультразвуком;

10.резание с помощью лазерного луча;

11.гибкие производственные системы;

12.детали круглого сечения;

13.поворачивать деталь вокруг ее оси;

14.двигать в сторону, двигать по направлению к детали;

15.глубина резания;

16.непрерывное вращение детали;

17.движение резца вдоль станины.

Task 2. Translate into English.

1.Токарный станок позволяет производить детали круглого сечения.

2.Деталь зажимается в патроне или на планшайбе токарного станка.

3.Резец может двигаться как вдоль станины, так и под прямым углом к ней.

4.Современные токарные станки часто имеют циф­ровое управление.

«MILLING MACHINE»

In a milling machine the cutter (фреза) is a circular device with a series of cutting edges on its circumfer­ence. The workpiece is held on a table that controls the feed against the cutter. The table has three possible movements: longitudinal, horizontal, and vertical; in some cases it can also rotate. Milling machines are the most versatile of all machine tools. Flat or contoured surfaces may be machined with excellent finish and ac­curacy. Angles, slots, gear teeth and cuts can be made by using various shapes of cutters.

Drilling and Boring Machines

To drill a hole usually hole-making machine-tools are used. They can drill a hole according to some specification, they can enlarge it, or they can cut threads for a screw or to create an accurate size or a smooth finish of a hole.

Drilling machines (сверлильные станки) are differ­ent in size and function, from portable drills to radial drilling machines, multispindle units, automatic produc­tion machines, and deep-hole-drilling machines.

Boring (расточка) is a process that enlarges holes pre­viously drilled, usually with a rotating single-point cut­ter held on a boring bar and fed against a stationary workpiece.

Shapers and Planers

The shaper (поперечно-строгальный станок) is used mainly to produce different flat surfaces. The tool slides against the stationary workpiece and cuts on one stroke, returns to its starting position, and then cuts on the next stroke after a slight lateral displacement. In general, the shaper can make any surface having straight-line elements. It uses only one cutting-tool and is relatively slow, because the return stroke is idle. That is why the shaper is seldom found on a mass production line. It is, however, valuable for tool production and for workshops where flexibility is important and relative slowness is unimportant.

The planer (продольно-строгальный станок) is the largest of the reciprocating machine tools. It differs from the shaper, which moves a tool past a fixed workpiece because the planer moves the workpiece to expose a new section to the tool. Like the shaper, the planer is intended to produce vertical, horizontal, or diagonal cuts. It is also possible to mount several tools at one time in any or all tool holders of a planer to execute multiple simultane­ous cuts.

Grinders

Grinders (шлифовальные станки) remove metal by a rotating abrasive wheel. The wheel is composed of many small grains of abrasive, bonded together, with each grain acting as a miniature cutting tool. The process gives very smooth and accurate finishes. Only a small amount of material is removed at each pass of the wheel, so grinding machines require fine wheel regulation. The pressure of the wheel against the workpiece is usually very light, so that grinding can be carried out on fragile materials that cannot be machined by other conventional devices.

Vocabulary:

milling machine - фрезерный станок

series - серия, ряд

cutting edge - режущий край, острие

circumference - окружность

to feed - подавать

longitudinal - продольный

horizontal - горизонтальный

vertical - вертикальный

versatile - универсальный

flat - плоский

contoured - контурный

angle - угол

slot - прорезь, паз

gear teeth - зубы шестерни

drill - дрель, сверло, сверлить

hole - отверстие

to enlarge - увеличивать

thread - резьба

portable - портативный

unit - единица, целое, узел

previously - ранее

to slide - скользить

stroke - ход

lateral - боковой

displacement - смещение

straight - прямой

idle - на холостом ходу

workshop - цех, мастерская

to mount - крепить

holder - держатель

to execute - выполнять

simultaneous - одновременный

multiple - многочисленный

grinder - шлифовальный станок

wheel - круг, колесо

bonded - скрепленый

to remove - удалять

pass - проход

fine - точный

conventional - обычный

device - устройство, прибор

fragile - хрупкий

General understanding:

1. What is the shape of a cutter in a milling machine?

2. What moves in a milling machine, a table or a cutter?

3. What possible movements has the table of a milling machine?

4. What kind of surfaces and shapes may be machined by a milling machine?

5. What can we use a drilling machine for?

6. What kinds of drilling machines exist?

7. What is rotated while boring, a cutter or a work-piece?

8. Describe the work of\a shaper (planer).

9. What must be done to execute multiple simultane­ous cuts on a planer?

10. What is the working tool in a grinder?

11. Can we obtain a very smooth surface after grind­ing and why?

12. Can we grind fragile materials and why?

Task 1. Translate into English.

1. Токарный станок все еще остается самым важным станком.

2. Все современные токарные станки оборудованы
   электроприводами.

3. Движение инструмента контролируется с высокой точностью.

4. Электропривод позволяет обрабатывать заготов­ку на различных скоростях.

«DIES»

Dies are tools used for the shaping solid materials, especially those employed in the pressworking of cold metals.

In presswork, dies are used in pairs. The smaller die, or punch, fits inside the larger die, called the matrix or, simply, the die. The metal to be formed, usually a sheet, is placed over the matrix on the press. The punch is mounted on the press and moves down by hydraulic or mechanical force.

A number of different forms of dies are employed for different operations. The simplest are piercing dies (про­бивной штамп), used for punching holes. Bending and folding dies are designed to make single or compound bends. A combination die is designed to perform more than one of the above operations in one stroke of the press. A progressive die permits successive forming op­erations with the same die.

In coining, metal is forced to flow into two matching dies, each of which bears a engraved design.

Wiredrawing Dies

In the manufacture of wire, a drawplate (волочиль­ная доска) is usually employed. This tool is a metal plate containing a number of holes, successively less in diameter and known as wire dies. A piece of metal is pulled through the largest die to make a coarse wire. This wire is then drawn through the smaller hole, and then the next, until the wire is reduced to the desired measurement. Wiredrawing dies are made from extremely hard materials, such as tungsten carbide or diamonds.

Thread-Cutting Dies

For cutting threads on bolts or on the outside of pipes, a thread-cutting die (резьбонарезная плашка) is used. It is usually made of hardened steel in the form of a round plate with a hole in the centre. The hole has a thread. To cut an outside thread, the die is lubricated with oil and simply screwed onto an unthreaded bolt or piece of pipe, the same way a nut is screwed onto a bolt. The corresponding tool for cutting an inside thread, such as that inside a nut, is called a tap (метчик).

Vocabulary:

chip - стружка

sharp - острый

friction - трение

content - содержание

range - диапазон ,

inexpensive - недорогой

to permit - позволять, разрешать

common - обычный

tungsten - вольфрам

ingredient - ингредиент

diamond - алмаз

tips - наконечники

ceramic - керамический

truing - правка, наводка, заточка

die - матрица, штамп

matrix - матрица

to employ - применять

to pierce - протыкать, прокалывать

to punch - пробивать отверстие

matching - сочетающийся, парный

coarse - грубый

wire - проволока

to draw - тащить, волочить

thread - резьба

hardened - закаленный

to lubricate - смазывать

to screw - привинчивать

nut - гайка

outside - наружный, внешний

inside - внутри, внутренний

Task 1. Find English equivalents in the text:

1. удалять металлическую стружку

2. острый режущий край

3. cодержание углерода

4. режущая способность

5. сталь для скоростного резания

6. правка шлифовальных кругов

7. гидравлическое или механическое давление

8. различные формы штампов

Task 2. Translate the following sentences into Russian:

1. Все резцы и фрезы должны иметь острую режущую кромку.

2. Во время резания режущий инструмент и деталь имеют высокую температуру и должны охлаждаться.

3. Углеродистые стали часто используются для из­готовления резцов потому, что они недорогие.

4. Быстрорежущие стали содержат вольфрам, хром и ванадий.

5. Алмазы используются для резания абразивных материалов и чистовой обработки поверхности твер­дых материалов.

6. Для различных операций используют различные штампы.

7. Волочильные доски для проволоки делаются из очень твердых материалов.

8. Резьбонарезные плашки и метчики используют­ся для нарезки резьбы снаружи и внутри.

«MECHANICAL PROPERTIES OF MATERIALS»

Materials Science and Technology is the study of ma­terials and how they can be fabricated to meet the needs of modern technology. Using the laboratory techniques and knowledge of physics, chemistry, and metallurgy, scientists are finding new ways of using metals, plastics and other materials.

Engineers must know how materials respond to exter­nal forces, such as tension, compression, torsion, bend­ing, and shear. All materials respond to these forces by elastic deformation. That is, the materials return their original size and form when the external force disap­pears. The materials may also have permanent deforma­tion or they may fracture. The results of external forces are creep and fatigue.

Compression is a pressure causing a decrease in vol­ume. When a material is subjected to a bending, shear­ing, or torsion (twisting) force, both tensile and compressive forces are simultaneously at work. When a metal bar is bent, one side of it is stretched and subjected to a tensional force, and the other side is compressed.

Tension is a pulling force; for example, the force in a cable holding a weight. Under tension, a material usu­ally stretches, returning to its original length if the force does not exceed the material's elastic limit. Under larger tensions, the material does not return completely to its original condition, and under greater forces the material ruptures.

Fatigue is the growth of cracks under stress. It oc­curs when a mechanical part is subjected to a repeated or cyclic stress, such as vibration. Even when the maximum stress never exceeds the elastic limit, failure of the material can occur even after a short time. No deformation is seen during fatigue, but small localised cracks develop and propagate through the material until the remaining cross-sectional area cannot support the maximum stress of the cyclic force. Knowledge of tensile stress, elastic limits, and the resistance of materials to creep and fatigue are of basic importance in engineering.

Creep is a slow, permanent deformation that results from steady force acting on a material. Materials at high temperatures usually suffer from this deformation. The gradual loosening of bolts and the deformation of components of machines and engines are all the exam­ples of creep. In many cases the slow deformation stops because deformation eliminates the force causing the creep. Creep extended over a long time finally leads to the rupture of the material.

Vocabulary:

bar - брусок, прут

completely - полностью, совершенно

compression - сжатие

creep - ползучесть

cross-sectional area - площадь поперечного сечения

cyclic stress - циклическое напряжение

decrease - уменьшение

elastic deformation - упругая деформация

elastic limit - предел упругости

exceed - превышать

external forces - внешние силы

fatigue - усталость металла

fracture - перелом, излом

loosen - ослаблять, расшатывать

permanent deformation - постоянная деформация

remaining - оставшийся

shear- срез

simultaneously - одновременно

to stretch - растягивать

technique - методы

tension - напряженность

to propagate - распространять (ся)

to bend - гнуть, согнуть

to extend - расширять, продолжаться

to meet the needs - отвечать требованиям

to occur - происходить

to respond - отвечать реагировать

to suffer - страдать

torsion - кручение

twisting - закручивание, изгиб

volume - объем, количество

rupture- разрыв

General understanding:

1. What are the external forces causing the elastic deformation of materials? Describe those forces that change the form and size of materials.

2. What are the results of external forces?

3. What kinds of deformation are the combinations of tension and compression?

4. What is the result of tension? What happens if the elastic limit of material is exceeded under tension?

5. What do we call fatigue? When does it occur? What are the results of fatigue?

6. What do we call creep? When does this type of permanent deformation take place? What are the results of creep?

Task 1. Find the following in the text.

1. отвечать требованиям современной технологии;

2. используя лабораторные методы;

3. новые способы использования металлов;

4. сжатие, растяжение, изгиб, кручение, срез;

5. возвращать первоначальный размер и форму;

6. внешняя сила;

7. постоянная деформация;

8. уменьшение объема;

9. растягивающие и сжимающие силы;

10. превышать предел упругости материала;

11. повторяющиеся циклические напряжения;

12. разрушение материала;

13. развитие и распространение мелких трещин;

14. сопротивление материалов ползучести и усталости.

Task 2. Translate into English the following sentences:

1. Упругая деформация - это реакция всех мате­риалов на внешние силы, такие, как растяжение, сжа­тие, скручивание, изгиб и срез.

2. Усталость и ползучесть материалов являются ре­зультатом внешних сил.

3. Внешние силы вызывают постоянную деформа­цию и разрушение материала.

4. Растягивающие и сжимающие силы работают од­новременно, когда мы изгибаем или скручиваем мате­риал.

5. Растяжение материала выше предела его упругости дает постоянную деформацию или разрушение.

6. Когда деталь работает долгое время под цикли­ческими напряжениями в ней появляются небольшие растущие трещины из-за усталости металла.

7. Ползучесть - это медленное изменение размера детали под напряжением.