Подберите подходящую пару к словам, обозначенным цифрами. Полученные словосочетания переведите

4.

4. Заполните пропуски предложенными словами:

Polythene, polystyrene, performance, thermoplastic, absorption, resistance

1. Modern plastics are characterized by attractive appearance, highest … and lowest cost.

2. Due to their toughness, strength, and corrosion … plastics have many significant applications.

3. … resins are characterized by high resistance to chemical and mechanical stresses at low temperatures and by very low … of water.

4. PVC is a … polymer with outstanding resistance to water, alcohols, and concentrated acids and alkalis.

5. …, a plastic made from ethane, is one of the most widely used polymers.

Задание IV

Найдите в тексте прилагательные в сравнительной и превосходной степени.

Найдите в тексте сказуемые в прошедшем времени.

Найдите в тексте примеры герундия и причастия I и определите их функции.

Задание V

1. Определите, какие из данных утверждений истинны, а какие ложны:

1. Plastics consist of carbon and other organic elements.

2. Plastics are low cost materials and are less reliable than metals.

3. Polystyrene has high resistance to chemical and mechanical stresses at low temperatures.

4. Epoxy resins cannot be used as adhesives due to their toughness.

5. PVC can be obtained in many forms.

6. Polythene is characterized by high density and high stiffness.

2. Ответьте на вопросы к тексту:

1. How can a successful design in plastic be achieved?

2. What role do plastics play in engineering nowadays?

3. What are main properties of thermosetting plastics?

4. What is PVC?

5. What are the typical applications of polystyrene?

Задание VI

Выполните письменный перевод текста.

Выполните устный пересказ текста, используя необходимые фразы.

Unit 8

Задание I

1. Подберите русские эквиваленты к следующим словам, содержащим интернациональные корни:

Erosion, ultrasound, electrode, stationary, rotation, modern, automatic, regulation, miniature, abrasive

2. Прочитайте следующий текст:

MACHINE TOOLS

Machine tools are used to shape metals and other materials. The material to be shaped is called the workpiece. Most machine tools are now electrically driven. Machine tools with electrical drive are faster and more accurate than hand tools: they were an important element in the development of mass-production processes, as they allowed individual parts to be made in large numbers so as to be interchangeable.

All machine tools have facilities for holding both the workpiece and the tool, and for accurately controlling the movement of the cutting tool relative to the workpiece. Most machining operations generate large amounts of heat, and use cooling fluids (usually a mixture of water and oils) for cooling and lubrication.

Machine tools usually work materials mechanically but other machining methods have been developed lately. They include chemical machining, spark erosion to machine very hard materials to any shape by means of a continuous high-voltage spark (discharge) between an electrode and a workpiece. Other machining methods include drilling using ultrasound, and cutting by means of a laser beam. Numerical controls of machine-tools and flexible manufacturing systems have made it possible for complete systems of machine-tools to be used flexibly for the manufacture of a range of products.

Lathe

Lathe is still the most important machine tool. It produces parts of circular cross-section by turning the workpiece on its axis and cutting its surface with a sharp stationary tool. The tool may be moved sideways to produce a cylindrical part and moved towards the workpiece to control the depth of cut. Nowadays all lathes are power-driven by electric motors. That allows continuous rotation of the workpiece at a variety of speeds. The modern lathe is driven by means of a headstock supporting a hollow spindle on accurate bearings and carrying either a chuck or a faceplate, to which the workpiece is clamped. The movement of the tool, both along the lathe bed and at right angle to it, can be accurately controlled, so enabling a part to be machined to close tolerances. Modern lathes are often under numerical control.

The various complicated machine-tools now used by engineers are designed to do the same jobs as the hammer, the chisel and the file, but very much more quickly and efficiently, and with much wider range of application. The vastly increased production of modern times would never have been possible without these machines to take the place of hand work, nor could the hand-worker ever produce the precision now needed.

The machine tools which have replaced the chisel and file and which shape the metal by removing parts of it are shapers, planers, milling machines, drilling and boring machines, grinders and lathes and those which have replaced the hammer and which press the metal into the required shape are steam hammers, forging and pressing machines and sheet metal work tools.

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