Упражнения

I. Найдите в тексте английские эквиваленты следующих слов и словосочетаний:

1. Промышленная технология, 2. звуковые колебания, 3. припой, 4. приводить в соответствие с (индивидуальными требованиями), 5. наковальня, 6. преобразователь, 7. частота, 8.образовать соединение, 9. защелка, 10. одноразовый, 11. бытовая электроника, 12. поглощение, 13. нагревание, 14. низкая температура плавления, 15. уровень мощности

II. Переведите на русский язык:

1. Dissimilar materials, 2. assembly, 3. connective bolts, 4. adhesives, 5. to sandwich, 6. interface, 7. a spiked energy director, 8. cell phone, 9. malleable materials, 10. dispersion of surface oxides, 11. be acoustically conductive, 12. in its infancy, 13. rigid, 14. to introduce vibrations, 15. semi-crystalline plastics

III.Вставьте нужное слово или словосочетание:

1.Ultrasonics are usually limited to small welds of thin … metals. 2. Ultrasonic welding employs … acoustic vibrations. 3. Ultrasonic welding equipment can be easily … to fit specifications of the parts being welded. 4. In ultrasonic welding the parts being welded are … between a fixed shaped nest and a sonotrode. 5. … is connected to the sonotrode, emitting high-frequency vibrations. 6. When welding plastics, the … of the two parts is specially designed. 7. Ultrasonics is used in manufacturing … medical tools. 8. Ultrasonics causes local melting of the plastic due to … of the vibration energy. 9. While welding thermoplastics, vibrations should be introduced … the joint to be welded. 10. Ultrasonic welding of metals occurs due to … of surface oxides and local motion of the materials.

IV. Переведите на английский язык:

1. Сварка ультразвуком часто используется для соединения разнородных материалов. 2. Оборудование для ультразвуковой сварки можно легко привести в соответствие с техническими требованиями. 3. При сварке ультразвуком используются акустические колебания высокой частоты. 4. Энергия ультразвука плавит место контакта свариваемых деталей. 5. Алюминий, медь, никель относят к пластичным металлам. 6. При ультразвуковой сварке термопластиков пластик плавится за счет поглощения энергии вибрации. 7. На заре метода ультразвуковой сварки ее могли использовать только для соединения твердых пластиков, проводящих звук. 8. Неизбежным следствием ультразвуковой сварки является выброс ультразвука. 9. Во многих случаях уровень шума превышает 80 децибел А. 10. Работникам, находящимся поблизости от места ультразвуковой сварки, необходимо защищать органы слуха.

V. Назовите слово по его определению:

1. Material capable of softening or fusing when heated and of hardening again when cooled;

2. Having a frequency above human ear’s audibility limit of about 20 000 hertz;

3. Manufactured parts fitted together into a complete structure or unit;

4. To build, fit or alter according to individual specifications;

5. Interception of radiant energy or sound waves;

6. The process of uniformly distributing small particles in a fluid or dividing white light into its coloured constituents;

7. (of metals) that can be hammered or pressed out of shape without tendency to return to it or to fracture;

8. Having the property of transmitting heat or electricity by conduct;

9. Nearness in space, time etc.;

10. Incidental or secondary product of manufacture’

11. A device that converts variations of one quantity into those of another;

12. A device for reducing or increasing voltage and current;

13. A unit used in comparison of power levels in sound intensity;

14. A unit of frequency equal to one cycle per second;

15. To go through the process of testing qualities of a thing or method.

Unit 11. UNDERWATER WELDING

Underwater welding refers to a number of distinct processes that are performed underwater. The two main categories of this techniques are wet underwater welding and dry underwater welding, both classified as hyperbaric welding. In wet underwater welding, a variation of shielded metal arc welding is commonly used, employing a waterproof electrode. Other processes that are used include flux-cored welding and friction welding. In each of these cases, the welding power supply is connected to the welding equipment through cables and hoses. The process is generally limited to low carbon equivalent steels, especially at greater depths, because of hydrogen-caused cracking. In dry underwater welding the weld is performed at the prevailing pressure in a chamber filled with a gas mixture sealed around the structure being welded. For this process, gas tungsten arc welding is often used, and the resulting welds are of high integrity.

The applications of underwater welding are diverse – it is often used to repair ships, offshore oil platforms and pipelines. Steel is the most common material welded. For deep water welds and other applications where high strength is necessary, dry underwater welding in most commonly used. Research into using dry underwater welding at depths of up to 1000 meters is ongoing. In general, assuring the integrity of underwater welds can be difficult, but it is possible using non-destructive testing applications, especially for wet underwater welds, because defects are difficult to detect if they are beneath the surface of the weld.

For the structures being welded by wet underwater welding, inspection following welding and assuring the integrity of such welds may be more difficult than for welds deposited in air. There is a risk that defects may remain undetected.

The risks of underwater welding include the risk of electric shock to the welder. To prevent this, the welding equipment must be adaptable to a marine environment, properly insulated and the welding current must be controlled. Underwater welders must also consider safety issues that normally divers face; most notably, the risk of decomposition sickness due to the increased pressure of inhaled breathing gases. Another risk, generally limited to wet underwater welding, is the build-up of hydrogen and oxygen pockets, because these are potentially explosive.

VOCABULARY

Wet underwater welding – влажная подводная сварка

Dry underwater welding – сухая подводная сварка

Hyperbaric – гипербарический, превышающий нормальное давление

Waterproof – водонепроницаемый, водоотталкивающий

Friction welding – сварка трением

Chamber – камера

Sealed - герметичный

Integrity - цельность

To assure - гарантировать

Non-destructive testing method – неразрушающий метод контроля

Insulated – изолированный (электр.)

Decomposition sickness – кессонная болезнь

Pocket – зд. пузырь