Stepanova_LM_AM-123_Stanki_Part2_1978-1 (Stepanova_LM_AM-123_Stanki_Part2_1978-1)

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Министерство высшего и среднего специального образования СССР


Московское ордена Ленина и ордена Трудового Красного Знамени

высшее техническое училище имени Н.Э.Баумана



Степанова Л.М.


Утверждена

редсоветом МВТУ











МЕТОДИЧЕСКАЯ РАЗРАБОТКА

ПО СПЕЦИАЛЬНОСТИ AM-I23


СТАНКИ

ч.II













Под редакцией Л.Т.Рогач
















Москва 1978




§1. A FEW WORDS ON MACHINE TOOLS.


What is a machine tool? A machine tool is a power-driven machine used to produce objects out of metal. Machinery is used to fashion metal objects because, with machines, the work can be performed much more precisely than by hand, with virtually no muscular effort and, much more rapidly. But not all machine tools perform precision work. Some, by their nature, are suited only for rough work, removing large chunks of metal and leaving relatively rough surfaces which are, later, to be smoothed and brought more closely to size1) by other machine tools better suited to fine work.

Some machine tools are 200 feet or more in length, — e.g.

special "transfer machines" which perform a whole series of

operations in timed sequence.2) Others are small enough to be carried by one man.

Some machine tools require great skill to operate. Others are semi-automatic and require only that the operator load the work into them, press a button or move a lever, and they do the work without further direction. Still others are so completely independent of human skill3) that, by virtue of what are called automation devices and numerical control - to be discussed later- they can load themselves, start, perform their function, stop, and unload, and can repeat the cycle of operations until stopped by hand or until the supply of workpieces is exhausted.

Some slowly fashion massive pieces. Others handle light work, producing it in but a fraction of a minute. Some machines have a light, delicate touch and can drill a hole, crosswise, through a human hair. At the other end of the scale stand the huge forging presses, the so-called "elephant tools" that can exert a squeezing force of 50,000 tons and are used for produc- ing large light-metal forgings for the aircraft industry.

It is evident, then, that size and weight do not help much
in classifying machine tools.
Nor does the machine's product
help
4) to classify it, for the same result may often be ob-
tained from several airferent basic types of machine. It is
what a machine tool does, and how it does it, that tells us
what kind of a machine it is.

Machine tools are the backbone of the metalworking indust- ­ry without which no other machines could be made, and they are the only man-made objects capable of reproducing themselves. In fact there is scarcely anything made for the use of man that does not owe its existence, directly or indirectly, to the ma­-chine tool.5)


Notes:

  1. which are, later, to be smoothed and brought more closely to size - которые позднее должны быть обработаны начисто и дове­дены до более точного размера

  2. in timed sequence - в рассчитанной по времени последователь-

ности

  1. still others are so completely independent of human skill -третьи настолько не зависят от мастерства человека

  2. Nor does the machine»s product help - и продукция станка также не помогает ... (Эмфатическая инверсия)

5) that does not owe its existence, directly or indirectly, to
the machine tool -
что, прямо или косвенно, не было бы обя-

зано своим существованием станку.



Words and word combinations to be remembered.

direction - указание, инструкция

to fashion - придавать форму путем обработки

fine (work) - точная (обработка); (работа с малыми допусками)

to handle – обрабатывать

lever - рычаг

to load - загружать ; to unload – разгружать

machine tool - станок

semiautomatic machine tool - полуавтоматический станок

transfer machine - автоматическая линия

numerical control - цифровое программное управление

to operate - управлять

to perform (an operation) - выполнять (операцию)

power-driven - с механическим приводом

precisely - точно

rapidly - быстро

rough (work) - черновая (работа)

skill - умение, мастерство

smooth - ровный, гладкий; сглаживать, обрабатывать начисто

to suit - подходить, соответствовать

Exercises.


I. State the function of the Infinitive in the underlined sen­tences and translate them.


II. Give the nouns corresponding to the adjectives and translate them:

precise, rapid, natural, rough, long, skillful, direct,independ-ent, human.


III. Look through the text once more and find equivalents for:

намного точнее; чем вручную; выполняет точную работу; доведена до более точного размера; нажать кнопку; без дальнейших указаний; цифровое программное управление; запас заготовок; всего лишь за долю минуты; основа металлообрабатывающей промышленности; прямо или косвенно.


IV. Insert the proper Infinitive, state its function and tran­-slate the sentences.


to be carried, to be used, to load, to operate, to be loaded, to press, to handle, to exert.

1. The work ... into the machine-tool is a circular casting.

2. Automation devices can handle pieces which are too massive

... by a man.

3. Some machine-tools require great skill. ... such a machine-

tool one should acquire proper knowledge and experience.

4. Our new laboratory received machinery ... for precision

work.
5. ... light work, some machines have a light, delicate touch.

6. Our country produces huge forging presses which are large

enough ... a squeezing force of 50,000 tons.

  1. The operator only has ... button ... the work into the auto­-matic machine.



V. Answer the questions.

1. What is a machine tool?

2. What are the three main advantages of a machine tool?
3. Do all machine tools perform precision work?

4. Of what size are machine tools?

5. Is it equally difficult to operate different machine tools?

6. What are the functions of an operator when operating a semi-

automatic machine tool?

7. How much time does it take a machine tool to fashion a work-

piece?

8. Where are huge forging presses used?

9. Are machine tools classified according to their size, or

weight, or product?

10.Why are machine tools considered to be the backbone of the

metalworking industry?



VI. Retell the text.


VII. Make a written translation using a dictionary.(time limit

10 min.)

Ever since Roman times, man had known of the power energy of steam, but it was only after the proper machine tool had been built that an engine could be made sufficiently steam- tight to put that power to work in driving machinery.

It was the steam engine that brought about the Industrial Revolution that led, eventually, to our present high standard of living and to the production of immense quantities of goods. Yet the practical development of the steam engine by James Watt had to wait upon the invention of the boring machine (a machine tool) by another man. And even as we stand at the beginning of the Atomic Age, it is well to remember that neither the origin- ­al splitting of the atom, nor the subsequent developments to apply its energy to man’s use could have been achieved without machine tools to make the necessary equipment.


VIII. Make up a summary of the above text.



§2. THE LATHE.


The metal-cutting lathe is the oldest of all standard ma- ­chine tools. More types of operations can be performed on it than on any other machine. According to the shape of tool em­ployed, the way in which it is mounted, and the direction and the rate at which it is fed to the work, it is possible to per- ­form a wide variety of operations, e.g. turning, boring, drill- ­ing, facing, etc.

These are only a few of the many operations that can



bе performed on the "engine lathe", so called because the earliest types were driven by steam engines.

There are other types of lathes that vary in their ability to perform work automatically, ranging up to the automatic screw machine which, as its name implies, is fully automatic in operation.

Lathes are made in a wide variety of designs and sizes1), nevertheless, every lathe consists essentially of a bed, head-stock, tailstock and carriage.

The main casting of an engine lathe is a horizontalmember called a "bed"2). Planed surfaces on top of the bed, called "ways" or "vees", align the headstock and tailstock and guide the carriage so that it moves longitudinally parallel to the axis of the machine. A chip pan under the bed collects chips and cutting fluid when one is used.

The headstock is mounted on the inner ways at the left

end of the bed. On some lathes the headstock casting supports shafts and encloses a train of gears that rotate the headstock spindle at rpm which are suited to the operating conditions of different jobs.

The tailstock is mounted on the inner ways, at the right end of the bed, to align it with the headstock. It is adjust­- able on the bed longitudinally so that it may be positioned wherever needed3) to support workpieces that are held on cen­- ters. When the workpiece is held with a chuck or on the large faceplate, the tailstock holds tools that may be used to per- ­form operations.

The lathe's carriage is a subassembly that is mounted on the outer ways of the machine hetween the headstock and tail-stock. Its function is to hold and move the turning and boring tools that are used on the machine. The principal parts of the carriage are the saddle, the cross slide, the tool post, and the apron.



Notes:


1) Токарные станки изготовляются самых разных размеров и кон­струкций.

2) Основная литая часть токарного станка - это горизонтально-

расположенный узел, называемый станиной.

3) Её можно перемещать по станине в продольном направлении, так


чтобы установить там, где нужно.



Words and word combinations to be remembered:

adjustable - регулируемый

to align - устанавливать соосно, центрировать

apron - фартук

bed - станина

carriage - суппорт

to guide - направлять

headstock - передняя бабка

lathe - токарный станок

engine lathe - (универсальный; токарно-винторезныя станок

longitudinally - продольно, в продольном направлении

member - элемент (конструкции)

раn - поддон

to position - устанавливать

saddle - салазки

shaft - вал, ось

subassembly - узел

taiistock - задняя бабка

vees - V-образные направляющие.

ways - направляющие (станка)

automatic screw machine - винторезный автомат

cross slide - поперечные салазки суппорта

cutting fluid - смазочно-охлаждающая жидкость

r.р.m. - revolutions per minute - оборотов в минуту

tool post - резцедержатель

train of gears - система (набор) шестерен




Exercises.



I. Look through the text once more and find equivalents for:

чем на любом другом станке; в зависимости от того, как он укреплен; самые первые типы; много различных операций; как показывает само название; вплоть до; режим работы; смазочно-охлаждающая жидкость; он (резец) подается к заготовке


II. Put the verbs in brackets into Active or Passive and
translate the sentences.



1. The lathe bed is the foundation on which the lathe (tо build).

2. There are two sets of ways on the lathe, the outer way's (to

guide) the carriage, and the inner ways (to keep) the head—

stock and tailstock in line. *

3. The headstock, carriage, and tailstock (to align) parallel to the axis of the spindle through the entire length of the bed.






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