Text 1 Machine Tools

UNIT FOUR MACHINE TOOLS

Просмотрите текст и выполните следующие задания.

I. Используя специализированный англо-русский словарь по технологии машиностроения и металлообработке, переведите следующие слова и словосочетания и запомните их:

cut (v,n)

machine-tool

machine-shop

equipment

to work (metals)

work (workpiece)

to remove

turning machine (lathe)

drilling machine

boring machine

milling machine

grinding machine

to confrol

cutting edge

feed (n)

II. Переведите следующие именные группы, обращая внимание на перевод слов в функции определения:

machine-tool industry; arms industry; work-holding device, feed motion; cutting-tool material; machine-tool production.

III. Проанализируйте состав следующих слов:

overheated, uncut, machinable, machinability

IV. Выпишите из второго и третьего абзацев слова (3), которые можно отнести к «ложным друзьям переводчика». Найдите по словарю и выпишите правильные значения этих слов.

V. Определите функцию местоимения “ it ” в первом предложении первого абзаца и переведите его вместе с относящимися к нему словами.

VI. Найдите в первом абзаце предложение с эмфатическим оборотом и переведите его.

VII. Переведите следующие предложения с эмфазой:

1. It is the addition of copper, zinc and iron that makes aluminium stronger.

2. It is copper that is used for making electrical contacts and wires because of its high electrical conductivity.

3. It was Whitney who invented the milling in the United states in 1818.

4. It was not until 1862 that the first fully universal milling machine was built by J.R.Brown of the United States.

VIII. Определите функцию инфинитива в последнем предложении первого абзаца и переведите его вместе с относящимися к нему словами.

IX. Найдите во втором абзаце инфинитив в функции части сказуемого и переведите его вместе с относящимся к нему подлежащим.

X. Переведите следующие предложения, обращая внимание на функцию причастия I:

1. The workpiece being machined has a large diameter.

2. Being subjected to a high load the casting cracked.

3. Having alloyed copper with tin, the Greeks and Romans obtained a new alloy called “bronze”.

4. Depending on the percentage of carbon steels can be divided into low, medium and high carbon steels.

5. Being one of the strongest metals steel is used for products where great strength is required.

6. Bronze is an alloy containing primarily copper and tin.

7. The metals being electrical conductors will make very suitable electrodes.

XI. Проанализируйте последнее предложение третьего абзаца, определите залог сказуемого и переведите предложение на русский язык.

XII. Переведите текст с учетом выполненных заданий. Первый абзац переведите письменно.

1. It is known that cutting is one of the oldest arts practised in the stone age but the cutting of metals was not found possible until the 18^th century. At the inception of the steam engine no machine tool industry existed—the whole of this industry is the product of the last two hundred years. The century from 1760 to 1860 saw the establishment of enterprises producing machine tools. It was in the time of Peter the Great when the first Russian machine tools were built. To develop the arms industry it was necessary to have new equipment, in particular, tools for cutting metal.

2. Now nearly in every machine shop one can find a lot of machines being used for working metals. These cutting machines are generally called machine tools and are extensively used in different branches of engineering to produce machines, instruments and tools of all kinds. The function of a machine tool is to hold a work and a cutting tool and to move them relative to each other to obtain the proper cutting action at economic speed. Fundamentally, all machine tools remove metal and can be divided into the following categories: turning machines (lathes), drilling machines, boring machines, milling and grinding machines.

3. All machine tools must provide work-holding and tool-holding devices and means for accurately controlling the depth of the cut. The relative motion between the cutting edge of the tool and the work is called the cutting speed; the speed in which uncut material is brought into contact with the tool is called the feed motion. Means must be provided for varying both. Because an overheated tool may lose its cutting ability, temperatures must be controlled. The amount of heat that is generated depends on the shearing force and the cutting speed. Because the shearing force varies with the material being cut and the tool material varies in its tolerance for high temperatures, the optimum cutting speed depends both on the material being cut and the cutting-tool material. It is also influenced by the rigidity of the machine, the shape of the workpiece, and the depth of the cut.

XIII. Составьте аннотацию на текст.

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