English
.pdfUnit I. Machinebuilding and metalcutting tools.
New words and word combinations:
1.working – обработка
2.skill – мастерство, способность
3.tools – инструменты
4.a lathe – токарный станок
5.capacity – мощность
6.to compare with – сравнивать
7.machining – обработка (металла)
8.a machine tool – станок
9.to engage in – вовлекать, нанимать
10.manufacture – производство
11.casting – литье
12.forging – ковка
13.stamping – штамповка Read and translate text:
Text A.
The working of metal in some form has engaged main's efforts thousands of
years. Over long stretches of the period, the products achieved were those resulting from skill of hand and brain in the use of crude or at best simple tools.
Reference to a lathe is found among the earliest of recorded writings. Such machines greatly extended man's productive capacity and enabled him to do things almost or entirely impossible previous to their invention. Nevertheless, they were very crude and ineffective when compared with the machines now used for machining metal.
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The machining of metal received its greatest impetus with the development of the steam engine. When this device was perfected to the point where a steady, economical and reliable source of power was assured, the development of tools and machines to which power could be applied followed rapidly.
Machines and machine products have made possible a standard of living unsurpassed in history.
It is difficult to determine the number of persons engaged in the machining of metal, such as screws, bolts, automobile engines and parts, airplane engines, locomotives and other products, in the manufacture of agricultural machinery, power transmitting machines, tools, boilers, j pumps, compressors, engines of all sorts, machinery used in the production of food, oil, textiles and of machines used to produce other machines.
The purpose of any machining operation is the production of various I parts of definite form, size and finish from raw materials in the form I of castings, forgings, bars, tubes, plates and stampings with the help of machine tools.
A machine tool is any power-driven non-portable machine designed primarily for shaping and sizing metal parts, by the progressive removal I of chips or by abrasion, from raw materials in the form of castings, forgings, bars, tubes, plates, and stampings. The machines for producing such raw materials are not machine tools according to the general usage of the term in the machine tool and machine-building industries. For example, rolling mills, forging machines, power presses, die-casting machines, moulding machines, brakes or other metalbending machines, I and power -driven hammers are not classed as machine tools. Metal-cutting machines, such as punching and shearing machines, are also excluded from the machine-tool classification.
New words and word combinations:
1.machinability – способность к обработке
2.to measure – измерять
3.forged steel - ковкая сталь
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4.hardness – жесткость
5.toughness – вязкость, прочность
6.tenacious – вязкий, прочный
7.cast-iron – чугун
8.malleable – ковкий
9.wrought iron – сварочное железо
10.slag – окалина
Read and translate text B: Text B. Machinability.
Machinability is a very complex mechanical property, and it has been impossible to measure it by any of the simpler mechanical tests. For example, ordinary steels having a Brinell number of not over 200 are readily machinable, while manganese steel of a Brinell well under 200 is not machinable. For cutting gear teeth in forged steel, the steel is heat-treated to a Brinell hardness of about 160 to 170. If the Brinell hardness is 150 or less, the material will be too tough and plastic to machine well. Copper and aluminium, because of their softness and toughness, are not easily machined.
Metals may be so strong that it is difficult to produce a tool capable of lifting the chip without frequent failures. Again, metals may contain hard constituents which quickly dull the point of the tool. Some metals are so strong and tenacious that, at what is considered as reasonable machining speed, the temperature developed soon limits the tool life. This is one of the most common causes of failure in commercial work.
Gray cast-iron machines readily because the flaky graphite particles in it cause the chip to break readily. Malleable cast iron also machines easily, but the nodular shape of the free carbon is not so effective in breaking ;the chip. Wrought iron, which carries many tiny threads of slag, machines easily until the harder slag dulls the tool.
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In spite of the difficulty of measuring machinability, it has been defined as the ease with which a material can be machined. The most machinable metal may be said to be one that permits the fastest removal of the greatest amount of material with a satisfactory finish before resharpening of the tool is required. Several methods have been used to evaluate machinability, such as the power consumed under some standard condition, the rate of tool penetration under some standard condition, the temperature produced under specified conditions, and so forth.
New words and word combinations:
1.turner – токарь
2.ways-guide – направляющие станка
3.carriage – суппорт, каретка
4.cross – slide – поперечные салазки, поперечный суппорт
5.clamp – зажимать, зажим
6.bed – станина
7.headstock – передняя бабка
8.tailstock – задняя бабка
9.feed mechanism – механизм подачи
10.mount – устанавливать, монтировать
11.casting – отливка
12.align – выпрямлять, центрировать
13.sleeve – втулка, рукав
14.traverse – двигаться, передвигаться
15.angle – угол
16.saddle – салазки, суппорт
17.apron – фартук токарного станка
18.taper bore – коническое отверстие
19.live centre – вращающийся центр, передний центр
20.dead centre – неподвижный центр
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21.chuck – патрон(зажимной)
22.rectangular - прямоугольный
23.facilitate – облегчать
24.graduate – градуировать
Read and translate text:
Text C. Engine lathe.
Modern lathes are highly efficient, accurate and complex devices, capable of doing a great quantity and variety of work. A well constructed engine lathe will, when properly operated, produce work accurate within. 001 of an inch or even less.
Motion is transmitted to modem lathes by means of individual motors. Sometimes the motor is direct mounted, while on other machines it is connected by means of a short belt, usually of the V-type.
The size or capacity of a lathe is given in terms of swing and length of bed. The swing refers to the diameter of work that can be rotated in the lathe. Thus a 16-inch lathe will swing work as large as 16 inches in diameter. The length of a lathe should not be confused with the maximum distance between center when the tailstock is moved to the rear end of the lame bed. The maximum distance between centers, however, determines the length of stock that can be machined.
Lathes are made in a wide variety of types and sizes, from the small precision lathe found in watch repair shops to the immense machine used in manufacturing big guns.
In recent years manufacturers have produced attachments which can be employed on a lathe to perform functions or operations formerly done on a special machine: a milling attachment, a boring attachment and a gear-cutting attachment. Such devices greatly extend the variety of work that can be performed on a lathe.
The most versatile machines of the lathe group are engine lathes. They are for metal-cutting operations and for cutting threads. Because of their ability to
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perform various kinds of work they require a great degree of skill to operate. A worker skilled m the use of a lathe is called a turner.
Engine lathes vary in size. The size of the engine lathe is based upon two measurements - approximate largest diameter that can be revolved over the ways and the total bed.
The engine lathe is fitted with a carriage and cross-slide for damping and holding the cutting tool.
In engine lathe the cutting tools are generally guided by the machine tools itself, in other words, they are operated mechanically, while in some lathes the cutting tools are guided by hand. The engine lathe consists essentially of the following basic parts: the bed, the headstock, the tailstock the feed mechanism, and the carriage.
All the principal units are mounted on a bed. The bed has the ways or guides along which the carriage and the tailstock travel. The bed is a strong casting, which function as a base for supporting and aligning the rest of the machine.
The work is clamped and rotated by the headstock. The headstock is located and firmly bolted to the left-hand side of the bed and carries a pair of
bearings in which the spindle rotates. Many modern lathes have a motor built into the headstock with the spindle serving as the motor shaft
The tailstock is located at the right-hand side of the bed. It is a casting carrying a non-rotating sleeve, which can be advanced or retracted by means of the revolving screw. The tailstock may be moved anywhere along the lathe bed and can be clamped in place at any point.
The cutting tool is traversed in both the longitudinal and cross directions, as well as at an angle, by means of the carriage. The carriage consisting of the saddle and apron is the movable part which slides between the headstock and tailstock.
New words and word combination.
1) to be responsible for - быть ответственным за
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2)to occur - случаться, иметь место
3)activity - деятельность
4)typing - печатание (на машинке)
5)wheel - колесо
6)axle - ось, мост (тех.)
7)hardware - аппаратура; аппаратные средства
8)gear - зубчатая передача, шестеренка
9)to provide - обеспечивать; предусматривать
10)to supply - снабжать, поставлять
11)source - источник
12)inanimate - неживой, неодушевленный
13)to supervise - смотреть, наблюдать за
14)to modify видоизменять
15)to set the machine - наладить машину
16)camshaft - кулачковый, распределительный вал
17)to fit - устанавливать, подгонять, прилаживать
18)assembly line - линия сборки
Read and translate into Russian. Text D. Machines Through the Age.
Mechanization, or the use of machines to do the work of animals or people, has been with us for centuries. There are six basic kinds of mechanization. Classification depends on whether machines, or combinations of animals and people, are responsible for the three fundamental elements that occur in every type of activity - power, action and control.
The first kind of mechanization is introduced by typing. In typing words, a body produced "the power" to drive a machine, bat the machine produces "action"; control is with the body. In one of the early mechanized devices, the horse and cart, an animal is responsible for power, while a person controls the mechanism, but the element responsible for action - the cart's wheels and axles - is mechani-
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cal. The horse and cart is a simple example of a mechanism that saves the human body from doing something.
In the second kind of mechanization, hardware is responsible for both power and action. In a car, for example, the wheels, gears and so on provide action while the engine supplies power.
Wind-and water-mills are another kind of mechanized device. Like cars, they use inanimated power source (air or water). But these power sources are not within a person's control.
The next 2 types of mechanized devices are all partly automatic. They are mechanically controlled; a person does not have to be present to supervise them. Simple automatic devices are not new. Soon after the first machine-tools appeared late in the 18th century, engineers modified them so that they could work by themselves for some of the time. An operator would set his machine so that it cut a piece of metal automatically. He would not have to do anything while the operation took place. The control devices here were camshafts and stops.
The fifth example of mechanization is semi-automatic equipment. Here people are required for only some elements of control. In this category are assembly lines with the conveyer systems of the 19th and 20th centuries with which, for instance, Henry Ford's first factories assembled cars. In this system parts move from one part of the factory to another on an automatic conveyer. But people have to be present. They stand next to the lines to fit things onto the parts as they move past.
Finally, the sixth kind of mechanization is truly automatic devices, such as transfer lines, computer controlled machine-tools, robots.
So to get a strict definition of automation, we can say: automation=mechanization+automatic control.
Unit II. Automation of production processes. New words and word combinations:
1) system approach - системный подход
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2)feedback - обратная связь
3)programmability - программируемость 4} management - управление
5)to intervene - вмешиваться
6)application - применение
7)to count - считать
8)to carry - нести
9)to cut - резать
10)to clamp - закреплять
11)routine - (зд.) режим работы
12)to detect - обнаруживать, открывать
13)a set ofряд, комплект
14)to turn out - (зд.) точить, обтачивать
15)sensors-датчики
16)flexible-гибкий
17)to be on the way - быть на подходе
18)machinery - машины, оборудование
Read and translate the text. Text A. Automation.
Automation is the third phase in the development of technology that began with the industrialization of the 18th century. First came mechanization which created the factory system and separated labour and management in production. Mechanization was a technology based on forms and applications of power Mass production came next. It was a technology based on principles of production and organisation Automation is a technology based on communication, computation and control.
The truly automated devices must possess one or more of the following elements: system approach programmability, feedback.
With a system approach, factories which make things by passing them through successive stages of manufacturing without people intervening to transfer lines,
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which made their debut in car factories before the Second World War, are considered automated systems. These carry components past lines of machine-tools which each cuts them automatically. People are not required; the machines clamp the parts out of themselves without a workman being present. Thus transfer lines are different from assembly lines where people are different from assembly lines where people are very much in evidence.
With programmability, a system can do more than one kind of job. An industrial robot is an automated machine. It works automatically and an opera tor can reprogram the computer that controls it to make the machine do different things.
Finally, feedback makes an automatic device vary its routine according to changes that take place around it. An automatic machine-too! with feedback would have sensors that detect, for example, if the metal it is cutting is wrongly shaped, if it is, the sensor instruct the machine to vary its routine accordingly Other examples of devices with feedback are robots with "vision" or other sensors that can "see" or "fee!" what they are doing.
Most examples of automation in factories today are not "programmable; neither do they work with feedback. They are simply sets of machine-tools linked together according to "systems4 approach. These mechanisms are inflexible. They turn out only one kind of part, which is all very well if the manufacturer wants to make thousands of identical components. But if he wants to change his routine, the machinery is not very useful. This is the case while automation is inflexible, flexible automation is on the way. Here, automated machinery has programmability and feedback and can turn out different kinds of components The equipment will make a tremendous difference to factory floors throughout the world. Flexible automation adds UD to a new industrial era.
New words and word combinations.
1.automatic tool changer (АТС) - автоматическое устройство смены инструмента;
2.chuck - патрон;
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