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MECHANICAL PROPERTIES OF MATERIALS





Контрольное задание №1

Для того чтобы правильно выполнить задание 1, необ­ходимо усвоить следующие разделы курса английского языка по рекомендованному учебнику:

1. Видовременные формы глагола: активный и пассивный залог - формы Indefinite (Present, Past, Future); формы Continuous (Present, Past, Future); формы Perfect (Present, Past, Future);
Особенности перевода пассивных конструкций на рус­ский язык.

2. Модальные глаголы: а) выражающие возможность:
can (could), may и эквивалент глагола саn — to be able; б) выражающие долженствование: must, его эквиваленты. to have to и to be to; should. Перевод модальных глаголов с последующим инфинитивом в пассивном залоге.

ВАРИАНТ № 1

I. Выберите правильный ответ, обращая внимание на особенности модальных глаголов и их эквивалентов. Переведите предложения на русский язык:

 

1.1. Before beginning an experiment one … carefully read all the instructions.

a) are able to

b) were allowed to

c) should

1.2. You … check a fuel level in the car tomorrow.

a) are able to

b) will have to

c) were to

1.3. They … easily define the properties of this material.

a) will be able to

b) shall have to

c) is to

1.4. You … use this instrument for measuring gas pressure.

a) is able to

b) ought to

c) may

 

1.5. The scientist … analyse the results of the test.

a) have to

b) is to

c) ought to

1.6. We … say that the discovery of atomic energy is as important as the discovery

of fire.

a) are to

b) will be able to

c) should

1.7. The machine tool which … perform turning is called the lathe.

a) is to

b) might

c) are able to

II. Выберите правильный ответ, обращая внимание на видовременную форму и залог сказуемого и переведите предложения на русский язык:

2.1. In present day organic chemistry new compounds … daily.

a) are synthesized

b) have been synthesized

c) are being synthesized

2.2. Much time … since the day when the first TV station began to operate.

a) has passed

b) are passing

c) will pass

2.3. Now solar energy and its usage … by a lot of research groups.

a) will be studied

b) are being studied

c) were studied

2.4. An interesting phenomenon in the field of aerodynamic effects … by Russian

scientists last year.

a) are being discovered

b) will be discovered

c) was discovered

2.5. Some new flexible lines … at our plant lately.

a) have been worked out

b) are worked out

c) will be worked out

2.6. At 8 o’clock tomorrow we … for a very important experiment.

a) will be preparing

b) shall be preparing

c) shall prepare

2.7. Great deposits of coal … in our region this year.

a) have been discovered +

b) had been discovered

c) will be discovered

III. Прочитайте и устно переведите текст, затем выполните тест по тексту:



The Microwave Oven

The first microwave oven was very big and heavy. At first, it was used exclusively in restaurants, railroad cars and ocean liners — places where large quantities of food had to be cooked quickly. In fact, it took decades after the invention of the microwave oven for it to be refined to a point where it would be useful to the average consumer.

A large increase in the use of microwave ovens has created a greater need for effective product design for microwave heating which ensures microbiological safety while maintaining product quality.

During conventional heating methods, the primary mechanism of heat transfer is either conduction or convection, depending of the nature of the food. In the microwave foods heat from the generation of heat within the food itself, not from the conduction of heat energy from hot air to the outer layer of the cooler product.

Microwaves penetrate the food and transfer their energy to dipolar or ionic molecules, which are present in all foods. The greater the concentration of dipolar molecules within particular areas in a food product, the faster that area of the product will heat. Some of this heat energy is transferred to cooler areas by conduction or convention, so helping the heating of other cooler areas, i.e. those areas which are less receptive to microwave heating.

The penetration depth of microwave energy depends on how rapidly the microwave energy is absorbed by the food product. If most of the energy is transferred to molecules at the surface of the product, the penetration will be shallow, with the bulk of the food heating mainly by convection or conduction.

ТЕСТ ПО ТЕКСТУ

Выберите правильный ответ и переведите предложения на русский язык:

3.1. At first the microwave oven was used in places where ….

a) there were no gas stoves

B) fast food had to be cooked

c)large quantities of food had to be cooked quickly

3.2. In the microwave foods heat from … .

a) the generation of heat within the food itself

b) the conduction of heat energy from hot air

c) the conduction of heat energy from the outer layer of the cooler product

3.3. Microwaves penetrate the food and … to dipolar or ionic molecules.

a) transfer their heat

b) transfer their energy

c) transfer their oscillation

3.4. The greater the concentration of …, the faster that area of the product will heat.

a) microwaves within particular areas in a food product

b) polar molecules within all areas in a food product

c) dipolar molecules within particular areas in a food product

3.5. The penetration depth of microwave energy depends on … .

a) how rapidly the microwave energy is absorbed by the food product

b) the power of microwave oven

c) the bulk of the food heating

ВАРИАНТ № 2

I. Выберите правильный ответ, обращая внимание на особенности модальных глаголов и их эквивалентов. Переведите предложения на русский язык:

1.1. User … install a specific driver in order to activate a peripherical device.

a) are able to

b) has to

c) shall have to

1.2. Engineers … know how materials respond to external forces, such as tension

and compression.

a) is to

b) may

c) must

 

1.3. The designers … work out a special line for their shop two years ago.

a) may

b) had to

c) was to

1.4. One … always inspect the machine tool before he turns it on.

a) have to

b) are able to

c) should

1.5. Automatic machines … to replace the old equipment of our shop.

a) are to

b) has to

c) ought to

1.6. In scientific work we … measure in units of the metric system.

a) ought to

b) must

c) has to

1.7. You … replace the tool by another one, why didn’t you do it?

a) were to

b) have to

c) are able to

II. Выберите правильный ответ, обращая внимание на видовременную форму и залог сказуемого и переведите предложения на русский язык:

2.1. We … new multipurpose machine tools last week.

a) get

b) got

c) will get

2.2. The experimental line …for two hours on Wednesday.

a) is working

b) works

c) will be working

2.3. The tests … by the end of the week.

a) will have been carried out

b) will carrying out

c) are carried out

2.4. Usually all these metal parts … automatically.

a) were cut

b) are cut

c) are being cut

2.5. The accuracy of machine tools … from year to year.

a) will be improved

b) are improving

c) will improve

2.6. They … the results of their research from 4 to 6 o’clock yesterday.

a) analysed

b) were analyzing

c) were analysed

2.7. We … this project for 2 years.

a) were developed

b) has been developing

c) have been developing

 

III. Прочитайте и устно переведите текст, затем выполните тест по тексту:

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-localized cracks develop and propagate through the material until the remain­ing cross-sectional area cannot support the maximum stress of the cyclic force.

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.

bar — брусок, прут fracture- перелом, излом

compression — сжатие tension - напряженность

creep — ползучесть torsion - кручение

fatigue - усталость металла twisting - закручивание, изгиб

rupture – разрыв

ТЕСТ ПО ТЕКСТУ

Выберите правильный ответ и переведите предложения на русский язык:

3.1. All materials respond to external forces … .

a) by resistance

B) by elastic deformation

c) by fracture

3.2. Compression is a pressure … .

a) causing a decrease in vol­ume

b) causing an increase in volume

c) causing small cracks

3.3. Under tension, a material usu­ally … if the force does not exceed

the material's elastic limit.

a) stretches, losing its original length

b) stretches, increasing its original length

c) stretches, returning to its original length

3.4.Fatigue oc­curs when a mechanical part is subjected to … .

a) a steady stress

b) high temperature

c) a repeated or cyclic stress

3.5. Creep occurs when material … .

a) is subjected to twisting

b) suffers from steady force acting on it

c) is subjected to cyclic stress

Контрольное задание № 2

Для того чтобы правильно выполнить задание 2, необходимо усвоить следующие разделы курса английского языка:

1. Пассивный залог (The Passive Voice) видовременных форм Indefinite, Continuous, Perfect.

2. Простые неличные формы глагола: Participle I (Pre­sent Participle), Participle II (Past Participle) в функциях оп­ределения и обстоятельства.

Инфинитив (Infinitive) в функции а) подлежащего, б) составной части сказуемого, в) определения, г) обстоятельства.

Gerund - герундий, простые формы.

ВАРИАНТ № 1

I. Выпишите предложения в которых инфинитив является обстоятельством и переведите их на русский язык.

1.1. We hope to get new data in a week or two.

1.2. To study the nature of light and colour Newton carried out many experiments

with a prism.

1.3. The famous Russian scientist Lebedev was the first to solve the problem of

synthetic rubber.

1.4. To study this phenomenon requires much knowledge.

1.5. This method is accurate enough to give reliable results.

1.6. Steel is the metal to be formed from iron with a definite amount of carbon.

1.7. To increase the productivity of the machine tool one should know the

characteristics of the material which is being machined.

II. Выпишите предложения, содержащие герундий и переведите их на русский язык.

2.1. One of the effects of heat is turning a solid into liquid.

2.2. The meeting began at 10 o’clock

2.3. In converting water into ice we do not change its composition.

2.4. Cooper is of great value, being a good conductor of electricity.

2.5. The boiling water changes into steam.

2.6. One cannot transform water into steam without heating it.

2.7. The air surrounding is a mixture of well-known gases.

III. Прочитайте и устно переведите текст, затем выполните тест по тексту:

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.

1. Fixed automation, sometimes called «hard automation» refers to automated machines in which theequipment configuration allows fixedsequence 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, automaticassembly machines and certain chemical processes.

2. Programmable automation is a form of automation for producing products in largequantities, 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 ofnon-productive time. Pro­duction rates in programmable automation are generally lower than in fixed automation 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 program.

3. Flexible automation is a kind of programmable au­tomation. Programmable automation requires time to reprogram 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.

Пояснения к тексту:

Rate – скорость, темп

Assembly machines – сборочные машины

Changeover – переход, переналадка

ТЕСТ ПО ТЕКСТУ

Выберите правильный ответ на вопросы по содержанию текста и переведите предложения на русский язык:

3.1. What is one of the limitations of hard automation?

a) The changeover of the equipment can be done very quickly.

b) The changeover of the equipment cannot be done very quickly.

c) The changeover of the equipment cannot be done at all.

3.2. Is it possible to use hard automation technology to make different processing

operations?

a) These machines allow making different processing operations.

b) These machines allow making only certain processing operations.

c) These machines allow making only ten processing operations.

3.3. How many units at a time can be produced using programmable automation

technology?

a) It is possible to produce several dozen units at a time.

b) It is possible to produce several units at a time.

c) It is possible to produce from several dozen to several thousand units at

a time.

3.4. What kind of automation requires little time to change over the equipment?

a) Fixed automation

b) Programmable automation

c) Flexible automation

3.5. Why is the number of products limited in flexible automation?

a) It is limited because this form of automation needs high initial investments.

b) It is limited to change over the equipment quickly and automatically.

c) It is limited so that to reprogram the production equipment.

ВАРИАНТ № 2

I. Выпишите предложения в которых инфинитив является обстоятельством и переведите их на русский язык.

1.1. Faraday made a series of experiments in order to produce a perfect optical

glass.

1.2. There are many questions to be answered in this field of science.

1.3. You may use this instrument in your experiments.

1.4. To prove their theory they made a lot of tests.

1.5. To estimate nowadays how many alloys there exist in the modern world is

difficult because their number increase daily.

1.6. This alloy is not tough enough to be used in this process.

1.7. To carry out this experiment will take you a lot of time.

 

II. Выпишите предложения, содержащие герундий. Переведите предложения на русский язык.

2.1. Using this device you can make new kinds of tests.

2.2. The experimentalist suggested purifying the solution by a new method.

2.3. We need devices improving the accuracy of measurements.

2.4. His offering new temperature conditions for the system will give greater effect.

2.5. While analyzing the quality of the alloy the engineer showed its negative

properties.

2.6. By subjecting air to very great pressure and cooling it is possible to transform it to

the liquid state.

2.7. The boiling solution has neither colour nor odour.

III. Прочитайте и устно переведите текст, затем выполните тест по тексту:

AUTOMATED PRODUCTION LINES

An automated production line consists of a series of workstations connected by a transfer system to move parts between the stations. This is an example of fixed automation, since these lines are set up for long produc­tion runs, making large number of product units and running for several years between changeovers. Each station is designed to perform a specific processing op­eration, so that the part or product is constructed stepwise as it progresses along the line. A raw work part enters at one end of the line, proceeds through each workstation and appears at the other end as a completed product.

Modern automated lines are controlled by program­mable logic controllers, which are special computers that can perform timing and sequencing functions required to operate such equipment. Automated production lines are utilized in many industries, mostly automobile, where they are used for processes such as machining and pressworking.

Machining is a manufacturing process in which metal is removed by a cutting or shaping tool, so that the remain­ing work part is the desired shape. Machinery and motor components are usually made by this process. In many cases, multiple operations are required to completely shape the part. If the part is mass-produced, an automated transfer line is often the most economical method of pro­duction. Many separate operations are divided among the workstations.

Pressworking operations involve the cutting and forming of parts from sheet metal. Several presses are connected together in se­quence by handling mechanisms that transfer the par­tially completed parts from one press to the next, thus creating an automated pressworking line.

Пояснения к тексту:

Machining – механическая обработка

Cutting tool – режущий инструмент

In sequence – один за другим

ТЕСТ ПО ТЕКСТУ

Выберите правильный ответ и переведите предложения на русский язык:

3.1. Workstations are connected by a transfer system … .

a) for delivering the components

b) to produce more units

c) to move parts between the stations

3.2. Automated production lines make large number of product units and run for …

a) several years between changeovers.

b) about ten years between changeovers

c) several months between changeovers

3.3. A finished part is produced … .

a) with each third cycle of the line

b) at the end of the working day

c) with each cycle of the line

3.4. Multiple operations are required … .

a) to partially shape the part

b) to completely shape the part

c) to improve the part

3.5. Several presses are connected together … .

a) in sequence by transfers

b) in sequence by handling mechanisms.

c) in sequence by drafting machines

 

Т Е К С Т Ы Д Л Я Ч Т Е Н И Я

-----------------------------------------------------------------------------------------------------------------------1. SEMI-CONDUCTOR

The term "Semi-conductors" means "half-conductor", that is, a material whose conductivity ranges between that of con­ductors and non-conductors of insulators.

They include a great variety of elements (silicon, germani­um, selenium, phosphorus and others), many chemical compounds (oxides, sulphides) as well as numerous ores and minerals.

While the conductivity of metals is very little influenced by temperature, the conductivity of semi-conductors increases sharply with heating and falls with cooling. This dependence has opened great prospects for employing semi-conductors in measuring techniques. Light as well as heat increases the con­ductivity of semi-conducting materials, this principle being used in creating photo resistances. It is also widely applied for switching on engines, for counting parts on a conveyer belt, as well as for various systems of emergency signals and for re-producing sound in cinematography. Besides reacting to light, semi-conductors react to all kinds of radiations and are there­fore employed in designing electronic counters.

Converting heat into electricity without using boilers or other machines was one of the most complicated engineering problems. This could be done by means of metal thermocouples which later were made of semi-conductors that generated ten times as much electricity as the metal ones.

Sunlight, like heat, can feed our electric circuits. Photo­cells made of semi-conducting materials are capable of trans­forming ten per cent of sun-ray energy into electric power. By burning wood which has accumulated the same amount of Molar energy, we obtain only fractions of one per cent of electric power. The electricity generated by semi-conductor ther­mocouples can produce not only heat but also cold, this prin­ciple being used in manufacturing refrigerators.

Semi-conducting materials are also excellent means of maintaining a constant temperature irrespective of the sur­rounding temperature changes. The latter can vary over a wide range, for example, from 50° below 0° to 100° above 0°.

Semi-conductors are determining the progress of radio en­gineering, automation, chemistry, electrical engineering and many other fields of science and technique.

2. AUTOMATION

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

The term automation is also used to describenonmanufacturing systems in which automaticdevices 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 theflyball governor, invented in 1788 by James Watt to control the speed of thesteamengine. The commonhousehold 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 greatlyfacilitated the use of feedback in manufacturing processes. Computers gave rise to the development of numerically controlled machines. The motions of these machines are controlled bypunched 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 itsdimensions 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.

AGRICULTURAL MASHINERY





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