Английский язык в сфере машиностроения. Учебное пособие для студентов направления подготовки бакалавров 15.03.01-Машиностроение

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The metal is usually tested for tensile strengthandelongation.The tensile strength rangesfrom 38,000 to 55,000 lbs. per square inch and the elongation is usually about 20 to 25 per cent.

VOCABULARY:

engineeringmetal – техническийметалл malleable – ковкий

shop – цех, мастерская shock – удар

grade – градус, качество, сорт melt – таять, плавить shortcoming – недостаток entirely – полностью

furnish – поставлять, снабжать tensile – растяжимый

resist – сопротивляться casting – отливка

anneal – отжигать, отпускать railroad – рельса

shrinkage – сокращение, сжатие crucible – тигель

onaccountof – вследствие, из-за conduct – проводить

range – ряд, предел, ставить в ряд overcome – преодолеть

elongation – удлинение, растягивание hence – следовательно

blastfurnace – доменная печь therefore – следовательно tenacity – вязкость, прочность coke – кокс, коксовать

wearingquality – изношенное качество becharged – расходуемый

open-hearth – открытый очаг, мартеновская печь cupolafurnace – вагранка

EXERCISES:

1. Answer the following questions:

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1. What is alloy grey iron?

2.What is alloy grey iron used for?

3.Where is malleable iron used in?

4.What is much stronger malleable iron or grey iron castings?

5.What is white iron?

6.What is the metal tested for?

7.What is the range of the tensile strength?

8.What is the range of the elongation?

2. Put questions to the sentences so that the highlighted words are answers:

1. Many experiments have been conductedto improve the qualities of grey iron castings.

2.Somecastingsrequire great strength and wearing qualities.

3. Malleable iron castings aremuch strongerthan grey iron castings. 4.Malleable ironcan be cast into very large bodies.

5.Metalsare usually tested for tensile, strength and elongation.

TEXT C: «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 grip-per 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

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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 an 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.theworkpiece or tool is 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 pickup — брать, подбирать arrangement — устройство

utilize — утилизировать, находить применение gripper — захват

grasp— схватывать spotwelding — точечная сварка continuous — непрерывный

arcwelding — электродуговая сварка

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spraypainting — окраска распылением frame — рама

spray-paintinggun — распылитель краски grinding — шлифование

polishing — полирование spindle — шпиндель manual — ручной labour — труд hazardous — опасный shift — смена

EXERCISES:

1. Answer the following questions:

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?

2. TranslateintoEnglish:

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.

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7. Использование гибкой автоматизации делает возможным производство разнообразной продукции.

UNIT 8

NON-FERROUS METALS

Text A: «Non-ferrous metals»

Text B: «Aluminium Alloys»

Text C: «Flexible Manufacturing System(FMS)»

TEXT A: «NON-FERROUS METALS»

Non-ferrous metals are more expensive than ferrous metals and are used only when some characteristic not possessed by iron or steel is essential or desirable in application. These characteristics are: high electrical and thermal conductivity, high corrosion resistance, nonmagnetic qualities, light weight, etc.

The metals most frequently used to make non-ferrous mend castings are copper, tin, zinc, lead, nickel, gold andaluminium. Some of the basic non-ferrous metals and their characteristics are described below.

Cooperis a reddish-brown, tough metal. It has very-high electric conductivity and high corrosion-resistant qualities Copper is used for making electrical contacts and wires, pipes, telephone cables, tanks, water heaters, etc.

Zincis a hard, brittle, bluish-white rnetal that is employed in the pure form as sheet-zinc.

Leadis a very heavy bluish-grey metal which is very soft. This metal is highly resistant to corrosion, but its strength is so low that it must be supportedby a coreof some other metal. Lead is used for liningpipes, acid tanks and coatingelectrical cables.

Aluminiumis a soft, silvery white metal. It is light in weight, has high corrosion-resistant qualities and is used for automobile and airplane parts as well as for making different light-weight objects used in everyday life such as: frames, cooking utensils, chairs, etc.

Tinis a silvery, corrosion-resistant metal. Tin is hardly used in pure form, but is employed as an alloying element.

Nickelis a hard, tough, silvery metal. It has high corrosion-resistant qualities and is used for plating-other metals such as iron or brass.

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There are many applications of non-ferrous metals in the unalloyed state, but in most cases, some alloying element is added.

The above-mentioned non-ferrous metals may be mixed in various proportions to form many alloys, chief among them being brasses, bronzes, and aluminium alloys. There is a wide range of use for non-ferrous alloys. Their nature differs greatly from that of the ferrous group. By varying the proportions of non-ferrous metals, alloys that are hard or soft, weak or strong, can be produced. When alloying, the metal with the highest melting point should be melted first, then the one with the next highest melting point, and so on until all of the metals that are to make up the alloy are melted together. For example, to make a red-brass alloy, the copper is melted first, then the zinc then the lead, and at last the tin. As soon as the mixture is hot enough to run the castings, it should be taken out of the furnace, otherwise the zinc, tin and lead may burn away.

Brassesare yellowish or reddish alloys of copper and zinc in different proportions (about 60 per cent copper and 40 per cent zinc, but some brasses contain as high as 90 per cent copper with only 10 per cent zinc). An addition of tin makes brasses stronger. Brasses are very ductileand may be treated without healing them. They are corrosionresistant and are used for making musical instruments, bearings, etc.

Bronzeis an alloy containing primarily copper and tin, but other elements may be added to the alloy to increase its properties such as hardness and resistance to wear. The most common bronzes are known as tin bronze, phosphor bronze, and manganese bronze. Straight bronze is usually a mixture of copper and tin, but there are many bronzes that contain zinc and lead, especially the cheap mixtures. Phosphor bronze may be made by adding a little phosphorus to the mixture. If phosphor tin is used and alloyed with the copper, better results will be obtained than if the phosphorus is mixed with the copper. Manganese bronze alloys are usually made by using both copper that contains from 5 to 15 per cent of manganese and copper that contains no manganese.

VOCABULARY:

posses – обладать, владеть zinc - цинк

essential – неотъемлемая brass - латунь

employ – нанимать, применять, soft – мягкий, использовать support – поддерживать, опора

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rust - ржаветь

core – сердечник, стержень chief - главный

tough – прочный, жѐсткий lead - свинец

acidtank – бак для кислоты tin - олово

utensils – принадлежности copper - медь

plating – гальваническое покрытие lining – облицовка

ductile – пластичный, вязкий damp – влажный, сырой bearings – подшипники, опора tinbronze – оловянистая бронза polish – полировать, шлифовать coating – покрытие, облицовка

reddish-brown – красновато-коричневый

thermalconductivity – теплопроводность, коэффициент теплоты bluish-white – голубовато-белый

EXERCISES:

1. Answer the following questions:

1.What ferrous metals do you know?

2.What are the main characteristics of non-ferrous metals?

3.What are the properties of copper and what is it used for?

4.What do you know about lead?

5.What purposes is aluminium used for?

6.What are the properties of other non-ferrous metals?

7.What metals are used for producing non-ferrous castings?

8.What do you know about brasses?

9.What do you know about bronzes?

10.What are the main properties of non-ferrous castings?

11.Why are attempts made to replace non-ferrous metals by ferrous ones?

2. Translate the sentences, paying attention to the wordmake:

1.Addition of copper, zinc and iron makes aluminium stronger.

2.The Soviet makes of new cranes are well known all over the world.

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3. The foreman makes the learners pay attention to the casting process.

TEXT B: «ALUMINIUM ALLOYS»

Aluminium is used extensively for castings that are to be light in weight, light in colour, or that must not rust. Since aluminium is too soft for making castings, it is necessary to mix some other metals with it. The metals that alloy freely with aluminium are copper, zinc, and iron. Usually, where aluminium alloys are made, the aluminium predominates.

All non-ferrous castings will take a high polish and will not rust so easily as the ferrous metals, a characteristic that makes them especially useful in wet or damp place. Non-ferrous metals are rather expensive and therefore nowadays scientists try to replace them with some ferrous alloys of lower cost possessing the same properties.

Aluminium alloys versus types of steel

There are aluminium alloys with somewhat-higher tensile strengths than the commonly used kinds of steel, simply replacing a steel part with an aluminium alloy might lead to problems.

With completely new metal products, the design choices are often governed by the choice of manufacturing technology. Extrusions are particularly important in this regard, owing to the ease with which aluminium alloys, particularly the Al–Mg–Si series, can be extruded to form complex profiles.

In general, stiffer and lighter designs can be achieved with aluminium alloys than is feasible with steels. For instance, consider the bending of a thin-walled tube: the second moment of area is inversely related to the stress in the tube wall, i.e. stresses are lower for larger values. The second moment of area is proportional to the cube of the radius times the wall thickness, thus increasing the radius (and weight) by 26% will lead to a halving of the wall stress. For this reason, bicycle frames made of aluminium alloys make use of larger tube diameters than steel or titanium in order to yield the desired stiffness and strength. In automotive engineering, cars made of aluminium alloys employ space frames made of extruded profiles to ensure rigidity. This represents a radical change from the common approach for current steel car design, which depend on the body shells for stiffness, known as unibody design.

Aluminium alloys are widely used in automotive engines, particularly in cylinder blocks and crankcases due to the weight savings that are possible. Since aluminium alloys are susceptible to warping at elevated temperatures, the cooling system of such engines is critical. Manufacturing techniques and metallurgical advancements have also been instrumental for

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the successful application in automotive engines.

An important structural limitation of aluminium alloys is their lower fatigue strength compared to steel. In controlled laboratory conditions, steels display a limit, which is the stress amplitude below which no failures occur – the metal does not continue to weaken with extended stress cycles. Aluminium alloys do not have this lower fatigue limit and will continue to weaken with continued stress cycles. Aluminium alloys are therefore sparsely used in parts that require high fatigue strength in the high cycle regime (more than 107stress cycles).

VOCABULARY:

extensively– широко rust– ржавчина mix– смешивать freely – свободно polish– польский replace– заменять inversely– обратно

employspace– использовать пространство unibody – цельным

cylinderblocks – блокицилиндров crankcases – картеры advancements– достижения application– применение

fatigue – усталость limit– предел amplitude– амплитуда weaken– ослаблять cycles– циклы sparsely– редко

EXERCISES:

1. Answer the following questions:

1.What is aluminium used for?

2.What metals do alloy freely with aluminium?

3.What characteristic do non-ferrous metals have got?

4. W he rear e aluminium alloys used?

5. W ha ti s an important structural limitation of aluminium alloys?

to conduct, conductor, conductivity; red, reddish; silver, silvery; to possess, possessive, possession; to plate, plating; to alloy, alloying; to resist, resistance, resistant; strong, strength, to strengthen; hard, hardness, to harden, hardening; pure, impure, purity, impurity, to purify, purification.

TEXT C: FLEXIBLE MANUFACTURING SYSTEM (FMS)

A Flexible Manufacturing System (FMS) is the current level of automation in the field of manufacturing. The application of FMS requires advanced technical know-how.

A Flexible Manufacturing System may be defined as a system dealing with high level distributed data processing and automated material flow using computer-controlled machines, cells, industrial robots, inspection machines and so on, together with computer integrated materials handling and storage systems.

Here manufacturing is considered to be a syhcmtwhich integrates different processes and requires a properly defined input to create the expected output.

Input may be raw material and/or data which have to be processed using various auxiliary components of the system, such as tools, fixtures and clamping devices, sensors and their feedback data. The output, may also be data and/or material which can be processed on further units (often called cells) of the manufacturing system.

An FMS can also be defined as a computer-controlled configuration of semi-independentwork stations and a material handling system designed to efficiently manufacture more than one kind of part number at low to medium volumes. The definition highlights the three essential physical components of an FMS:

a)standard numerically controlled machine tools;