Английский язык в сфере машиностроения. Учебное пособие для студентов направления подготовки бакалавров 15.03.01-Машиностроение
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b)a conveyance network to move parts and perhaps tools
between machines and fixturing stations;
c)an overall control-system that coordinates the machine
tools, the parts and the workpieces.
The number of machines in a system typically ranges from 2 to 20 or more. The conveyance system may consist of carousels, conveyors, carts, robots, automated guided vehicles, etc.
The FMS can be thought of as a distributed management information system linking together intelligent subsystems of machining, welding, painting, Flame cutting, sheet metal manufacturing, inspection, assembly, etc. and material handling and storageprocesses. Flexible manufacturing systems are regarded by many experts as being the best way to meet the demands of industry) They consider the FMS to be the future of the automated factory, or at least the minimally manned factory. And perhaps most significant that FMS is clearly the most obvious manifestation of computer-integrated manufacturing on the factory floor.
So it is possible to say that the FMS is of interest to manufacturers who produce more than one kind of part number at low to medium volumes. The FMSs provide a direct hardware/software solution to many economical and technical problems. The imortant aspect of these system is that the machine tools, conveyance and control devices combine to achieve increased productivity and maximum machine utilization without decreasing flexibility.
VOCABULARY:
cart - тележка (для перевозки палет между обрабатывающими участками)
cell - гибкая автоматизированная ячейка (модуль)
fixture - захват-держатель, захватное устройство (для ориентации детали с координатами режущего инструмента станка)
flexible - гибкий
manufacturingsystem – гибкая автоматизированная система; гибкое автоматизированное производство (ГАП)
hardware - аппаратные средства, аппаратура know-how - умение, технология
machine - обрабатывать на станке machinetool —станок
numericallycontrolledmachinetool - станок с числовым программным управлением (ПС), ЧПУ
manufacture - производство, изготовление, обработка
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manufacturing —производство; промышленный, производственный part - деталь; конкретная по конструкции деталь
process - обрабатывать processing -обработка
distributeddata - распределенная система обработки данных sensor - датчик
software - программное обеспечение, программные средства storage - хранение; складирование; хранилище, склад; process — процесс накопления (на автоматическом складе) store - хранить (на складе); накапливать (в память)
semi-independentworkstations -полузависимые станции (посты) intelligentsubsystem - подсистема искусственного интеллекта
EXERCISES:
1. Answer the following questions:
1.Which of the FMS definitions gives more complete characteristics of the system?
2.What is meant by input/output of the FMS?
3.What does the FMS conveyance system include?
4.What do you think about the future of the FMS? Do you agree with the conclusion of the text? Giveyourreasoning.
2. Find the English equivalents of the following Russian words and word combinations in the text:
передовая технология; автоматизированный поток материала; контрольные машины; автоматизированная система перемещения и складирования деталей (сервисная система); сырье; инструменты; захват-держатель; данные обратной связи; конкретная по конструкции деталь; станки; сварка; производство листового металла; отвечать требованиям промышленности; программное и аппаратное обеспечение; максимальное использование машин.
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UNIT 9
PROPERTIES OF ENGINEERING MATERIALS AND METHODS
OF TESTING THEM
Text A: «Properties of engineering materials and methods of testing them»
Text B: «Strength, Elasticity, Plasticity, Hardness» Text C: «Control system»
TEXT A: «PROPERTIES OF ENGINEERING MATERIALS AND
METHODS OF TESTING THEM»
Almost every substance known to man has found its way into the engineering workshop at some time or other. The most convenient way to study the properties and uses of engineering materials is to classify them into ‗families‘ as shown in figure below:
While using engineering materials in practice we must know their properties because they affect manufacture and application of materials. All engineering materials have definite characteristics which determine their abilities to assume external loads, because of which materials change their shape.
When a metal is treated or when machine parts and tools are in the process of work the metals which they are made of are subjectedto the imluence of externalforces. These forces are called "loads" and may have different characteristics: accordingtotheir value they may be small or large; according to the duration and character of their action they may be constantand impact. According to the influence of the loads upon the metal causingdifferent changes of its shape, loads are distinguished as compression, tensile, torsional, shearing, and bendingones.
By testing a metal under a load one can define what mechanical properties it has. In other words, one can determine strength, elasticity,
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plasticity, hardness and other properties of the metal. In order to have a clear conception of the metal properties it is subjected to tests on special devices and machines. The determination of these properties is made in the laboratory using a specimenfrom the metal to be tested. Let us consider some of the mechanical properties of metals.
VOCABULARY:
bending – изгиб, нагрузканасгиб determine - определять shearing – срез, нагрузканасрез torsinal - крученный
assume – принимать на себя, предполагать conception – представление
constant – постоянная externalloads – внешняя нагрузка value - величина
subject – подвергнуть чему-либо causing - причиняя externalforces – внешниесилы affect – действие
compression – сжатие, сжимание ability – способность
impact – динамическая(ударная) нагрузка
EXERCISES:
1. Answer the following questions:
1. Why is it necessary to know the properties of engineering materials? 2.To what forces are machine parts subjected in the process of work? 3.How are the loads distinguished according to their influence upon the metal?
4.What are the most important mechanical properties of metal? 5.What special devices are used for testing mechanical properties? 6.What is stress?
7.What is strain?
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2. Translate into Russian:
to penetrate, hardness, cross-section, to determine, to evaluate, plasticity, elasticity, to influence, unit stress, engineering materials, property, to subject, load, external forces, to cause, impact loads, compression loads, torsional loads, specimen, shearing loads, unit, surface, clamp, bending loads, rupture machine, extension, dial.
TEXT B: «STRENGTH, ELASTICITY, PLASTICITY, HARDNESS»
Strengthof metals is the property of hard materials to be subjected to the influence of external forces without incurring damage and without changing their shape. The ultimate tensile strength of a material is that unit stressdeveloped in the material by maximum slowly applied load that the material can resist without rupturing in a tensile test. A stressis the force within a body which resists deformation due toan externally applied load. If this load acts upon a surface ofunitarea, it is called a "unit force", and the stress resisting it is called a "unit stress". An external force acting upon an elastic material, the material is deformed and the deformation is in proportion to the load. This distortion or deformation is called "strain".
Special machines, called "rupture machines", are used to test metals for strength. Fig. 1shows one of these machines. When testing a specimen, the upper clampremains fixed and the lower one is being slowlylowered, thus causing the extensionof the specimen. The load upon the specimen may be easily determined at any moment by means of pointerindications on the dial.
Elasticityis the ability of a material to change its shape under the influence of external loads and return to its original form upon removal of the loads. All materials are elastic but the range of elasticity varies for different materials. Elasticity is evaluatedby means of the modulus of elasticity. The modulus of elasticity is the ratio of the unit stress S to the unit deformation ∆l within the proportional limit of the material to be tested
E =S/∆l.
For determining the elasticity of metals a rupture machine may be
used.
Plasticityis that property of a material when under the Influence of loads, specimens of different materials may elongate while their crosssection decreases. Plasticity is the opposite of elasticity. So, plasticity is the ability of material to change its form without breaking under the influence
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of load and preserve this changed form after removal of the load. For determining the plasticity of metals a rupture machine may be used too.
Hardnessof material is the property to resist deformation under applied load. Hardness is the most important mechanical property of metals. Hardness may also be defined as the ability ofmetals to resist penetrationof other harder materials or as resistance to wear.
VOCABULARY:
indication – индикация range - предел
dialindication – циферблатный modulus – модуль, индикатор elongate – удлиняться, растягиваться evaluate – оценивать
cross-section – поперечное сечение, strain - напряжение
ratio - отношение, пропорция torsion - кручение
preserue – сохранять(ся) extension - растяжение penetration – проникновение clamp – зажим, зажимать load – нагрузка, нагружать bymeansof - посредством
ultimatetensilestrength – предельное сопротивление разрыву rupturemachine – испытание(машина) на деформацию(разрыв) pointer – стрелка, указатель
EXERCISES:
1. Answer the following questions:
1.What is strength of metals? 2.What is elasticity of metals? 3.What is plasticity of metals?
2. Put questions to the sentences so that the highlighted words are answers:
1. The deformation test of a metal property is performed in a laboratory.
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2.By testing и metal onecan define its mechanical properties.
3.In some materials, such as stone or iron, the possible elastic deformation may be very small.
4.In some materials, such as lead, plasticity may imply an almost total absence of elasticity.
5.Elasticity is the capacity of the material to resist produced deformations without permanent change of form.
TEXT C: «CONTROL SYSTEM»
Computers have revolutionized manufacturing. They have given manufacturing engineers control over events in the factory. With this information, processes can be reorganized for maximum efficiency and production steps can be rearranged for maximum cost savings. You can know what is occurring on the floor now.
Because of computers tasks are done more quickly and accurately, it enables engineers to make changes or corrections that utilize equipment and people optimally.
An important quality of computers is that they are flexible. Change the program and you have a "new computer".
Software. Computers cannot run without software; that is, without some instructions on what to do. Software controls the flow of information in a computer system. The software makes a computer a calculator, a designer, a programmer, a cost estimator, an expert.
Simulation software is another type of software which is now becoming quite popular. This type of software lets you see your proposed factory layout at work "on paper".
Simulation software helps in the design and development of automated work cells, manufacturing systems and factories such as FMS.
An FMS without software is not flexible, has little use in manufacturing and is not even a system.
The main problems that FMS software should solve are as
follows:
Keep track of the materials being manufactured, determine the exact physical location in the system and perform the correct sequence of operations.
Prevent the different operations from interfering with each other. Determine error conditions and minimize their impact on the
system.
Keep management informed on parts, production, part programming, system status.
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Determine the best production schedule to meet due data and maximize machine utilization. Forecast system needs at due time - fixtures, tools, lubricants and coolants.
Direct in real-time the operations of people in charge of the above facilities. Compare actual and forecast performances.
Inform the plant management with the required data from FMS, for production planning and control, accounting and reporting. Thus, the FMS control system manages the total combination of devices in the system that contributes to the automatic operation of the production process. This includes the machine-tool controllers, the material handling system, the system monitoring devices, the system communications, and finally the system computer. Computer software supplies all the control management and monitoring functions that enable the system to achieve high utilization.
The control system is easily visualized by considering all the elements of the system in a structured arrangement according to its function. This structure and how each function of the structure relates to the overall system performance will be discussed later.
VOCABULARY:
chip - кристалл; чип; микросхема; интегральнаясхема computer - компьютер
supercomputer–суперЭВМ mini-supercomputer -суперминиЭВМ mainframecomputer – большаяЭВМ costsavings - снижениеиздержек (производства), экономия наиздержках
data от datum - (исходные) данные; факты, информация; base - база данных
facility - устройство; средство; оборудование hardware - аппаратное оборудование (ЭВМ)
layout - схема расположения; планировка; схема организации работ; программа
manage - управлять, руководить
management - управление (планирование, контроль) monitor - контролировать; управлять
monitoring - контроль
inreal-time - в истинном масштабе времени simulate - моделировать
simulation - моделирование
software — программное (математическое) обеспечение
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keeptrack (of) - следить за (ходом, развитием чего-л.) interferewith - мешать, служить препятствием peopleinchargeofsmth.–ответственныезачтол. visualize - мысленно представлять себе
EXERCISES:
1. Answer the following questions:
1.What is the role of computers in industry in general and in FMS in particularly?
2.What can you say about software?What are the main problems that software should solve?
3.What can you say about simulation software?
4.Now we say that the FMS control system manages the total combination of devices. Whatdowemeanbysayingthis?
2. Add facts from the text to the following sentences:
1.It is necessary to say that one of the important features of computers is that... .
2.The significance of simulation software is that....
3.As is known FMS software should solve a lot of problems, for example....
4.Summing it up, one must say that the FMS control system....
5.The task of FMS computer software is to....
6.It is necessary to say that we can understand the FMS control system easily if we consider....
UNIT 10
MEASURING TOOLS AND DEVICES
Text A: «Measurement»
Text B: «Measuring tools»
Text C: «Control system architecture»
TEXT A: «MEASUREMENT»
The size and shape of all machine parts should be in accordance with the corresponding drawing. The produced parts should be checked by
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means of measurement, which generally involves comparison either with some accepted standard or with a mating part. The significance of any measurement is determined by the degree of accuracy to which the parts may be measured.
Depending on measurements different measuring tools can be used such as rules, slide gauges, vernier calipers, depth gauges, dial indicators, micrometers, clearance gauges, inside andoutside calipers, plug gauges, bevels, universal protractors, etc.
VOCABULARY:
pluggauges – калибр-пробки mating – парный depthgauges – глубиномер ruler – линейка
universal – универсальный micrometers – микрометр, угломер slidegauges – раздвижнойкалибр; insidecalipers – нутромер
clearancegauge(s) – щуп(ы) штангенциркуль verniercaliper – штангенциркульснониусом outsidecaliper – кронциркульдлявнешнихобмеров dialindicator – индикаторциферблатный
bevels – малки, конусы; сниматьфаску,скашивать
EXERCISES:
1. Translate the following words and word combinations:
drawing, to measure, to involve, mating part, accuracy, slide gauges, vernier calipers, depth gauges, clearance gauges, micrometer, inside calipers, outside calipers, to graduate, internal diameters, to slide, adjusting screws, lock nut, tapped hole
2. Translate the sentences into Russian, paying attention to the highlighted words:
1.The principle involvedin the operation of the micrometer is explained in technical text-books.
2.The instruction on the use of this dial indicator is rather involved.