Методичка по английскому языку для ИТС (пр. С.С.Иванов)

VOCABULARY

Exercises

Найдите в тексте английские эквиваленты следующих слов и словосочетаний:

1) дуговая сварка плавящимся электродом в среде инертного газа; 2) дуговая сварка плавящимся электродом в среде защитного газа; 3) дуговая сварка плавящимся электродом в среде активного газа; 4) источник постоянного тока; 5) цветные металлы; 6) полуинертный газ; 7) двуокись углерода; 8) разнообразие, многосторонность применения; 9) дуговая

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сварка под флюсом; 10) защитный газ; 11) сварка порошковой проволокой (трубчатым электродом); 12) точечная сварка; 13) сварка электрозаклепками; 14) подключать, соединять; 15) включатель.

Переведите на РЯ следующие слова и словосочетания:

1) wire feed unit; 2) welding gun; 3) non-ferrous metals; 4) resistance spot welding; 5) dissipation; 6) conduit; 7) gas hose; 8) air volatility; 9) to alleviate a problem; 10) key parts; 11) to initiate the wire feed; 12) to strike the arc; 13) the conduit tip; 14) to reduce spatter; 15) to be firmly secured; 16) gas nozzle; 17) tanks of gas; 18) high heat operation; 19) to drive (the electrode) through the conduit; 20) thermal conductiveness.

Найдите в тексте синонимичны данным слова и выражения:

to decrease, control switch, welder, to employ a gas, widely, medium of atmosphere, to start the wire feed, to initiate an arc, metal droplets, wire-feed unit.

Вставьте нужное слово или словосочетание.

1. Aluminum and copper are ... metals. 2. Gas protecting the weld area is called a ... gas. 3. GMAW is given preference for its speed and... . 4. The movement of the surrounding atmosphere can cause ... of the shielding gas. 5. The problem can be ... by increasing the shielding gas output. 6. The ... initiates the wire feed. 7. The contact tip, made of copper, ... the electrical energy to the electrode. 8. Before arriving at the contact tip, the wire is protected and guided by the ... . 9. The ... is used to evenly direct the shielding gas into the welding area.

Дайте полную форму следующих аббревиатур:

GMAW, MAG, MIG. DCEN. DCEP, PAW.

Unit 4. ULTRASONIC WELDING

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Ultrasonic welding is an industrial technique whereby high-frequency ultrasonic acoustic vibrations are used to weld objects together, usually plastics, and especially for joining dissimilar materials. This type of welding is used to build assemblies that are too small, too complex or too delicate for more common welding techniques. In ultrasonic welding there are no connecting bolts, nails, soldering materials or adhesives necessary to bind the materials together.

For joining complex injection-molded thermoplastic parts, ultrasonic equipment can be easily customized to fit the exact specifications of parts being welded. The parts are sandwiched between a fixed shaped nest (anvil) and a sonotrode (horn) connected to a transducer which is lowered down, and a 20 kHz low-amplitude acoustic vibration is emitted. Common frequencies used in ultrasonic welding of thermoplastics are 15 kHz, 30 kHz, and 40 kHz. When welding plastics, the interface of the two parts is specially designed to concentrate the melting process. One of the materials traditionally has a spiked energy director which contacts the second plastic part. The ultrasonic energy melts the point of contact between the parts, creating a joint. This process is a good automated alternative to glue, screws or snap-fit designs. It is typically used with small parts, e.g. cell phones, consumer electronics, disposable medical tools, toys etc., but it can be used on parts as large as a small automobile instrument cluster. Ultrasonics can also be used to weld metals, but they are typically limited to small welds of thin, malleable metals, e.g. aluminum, copper, nickel. Ultrasonics would not be used in welding the chassis of an automobile or in welding pieces of a bicycle together, because of the power levels required.

Ultrasonic welding of thermoplastics causes local melting of the plastic due to absorption of vibration energy. The vibrations are introduced across the joint to be welded. Ultrasonic welding of metals is not due to heating, but instead occurs due to high-pressure dispersion of surface oxides and local motion of the materials. Although there is heating, it is not enough to melt the base materials. Vibrations are introduced along the joint being welded.

Ultrasonic welding appeared in mid-1960s and is rapidly developing. In its infancy only hard plastics could be welded because they were acoustically conductive and had a low melting point. Today ultrasonic welding machines have much more power, enough to weld less rigid, less acoustically conductive materials such as semi-crystalline plastics, as well as higher melting point materials. The patent for the ultrasonic method for welding rigid thermoplastic parts was awarded to R. Soloff in 1965.

An inevitable by-product of ultrasonic welding is a blast of ultrasonic sound. The lower frequencies of 15 kHz and 20 kHz typically emit a squeal that can be heard by operators. In many cases the noise level will exceed 80 dBa and

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Exercises

Найдите в тексте английские эквиваленты следующих слов и словосочетаний:

I) 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.

Переведите на РЯ следующие слова и словосочетания:

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) semicrystalline plastics.

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.

Переведите на АЯ следующие предложения.

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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.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.

Назовите слово по его определению.

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

Having a frequency above human ear‘s audibility limit of about 20 000

hertz.

Manufactured parts fitted together into a complete structure or unit.

To build, fit or alter according to individual specifications.

Interception of radiant energy or sound waves.

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

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

Having the property of transmitting heat or electricity by conduct.

Nearness in space, time etc.

Incidental or secondary product of manufacture.

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

A device for reducing or increasing voltage and current.

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

A unit of frequency equal to one cycle per second.

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

Unit 5. 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;

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Переведите на РЯ следующие слова и словосочетания:

1) hypebaric welding; 2) dry underwater welding; 3) wet underwater welding; 4) a sealed chamber; 5) gas mixture; 6) prevailing pressure; 7) diverse applications; 8) high strength; 9) adaptable to marine environment; 10) properly insulated; 11) safety issue; 12) breathing gases; 13) to inhale; 14) build-up of hydrogen pocket; 15) potentially explosive.

Переведите на АЯ следующие предложения.

1. Сварка под давлением имеет две основные разновидности - влажная и сухая подводная сварка. 2. Влажная подводная сварка является разновидностью сварки под флюсом. 3. Подводная сварка обычно используется лишь для низкоуглеродистых сталей. 4. Водород, содержащийся в наплавленном металле, снижает его пластичность и вызывает растрескивание. 5. При подводной сварке используется водонепроницаемый электрод. 6. При сухой подводной сварке шов выполняется в герметичной камере, заполненной газовой смесью. 7. Сухая подводная сварка обеспечивает более прочный и надежный шов. 8. Для проверки подводных швов используются различные неразрушающие методы контроля. 9. При подводной сварке сварщик может получить удар электротока 10. Сварочное оборудование должно быть приспособлено для работы в морской среде.

Unit 6. OXY-ACETYLENE WELDING (PREHEATING)

The practice of heating the metal around the weld before applying the torch flame is desirable one for two reasons. First, it makes the whole process more economical; second, it avoids the danger of breakage through expansion and contraction of the work as it is heated and as it cools.

When it is desired to join two surfaces by welding them, it is, of course, necessary to raise the metal from the temperature of the surrounding air to its melting point, i.e. an increase in temperature up to one thousand - three thousand degrees. To obtain this entire increase of temperature with the torch flame is very wasteful of fuel and of the operator‘s time. The total amount of heat necessary to put into metal is increased by the conductivity of that metal because the heat applied at the weld is carried to other parts of the piece being handled

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until the whole mass is considerably raised in temperature. To secure this increase various methods of preheating are adopted.

As to the second reason for preliminary heating, it is understood that the metal added to the joint is molten at the time it flows into place. All the metals used in welding contract as they cool and occupy a much smaller space than when molten. If additional metal is run between two adjoining surfaces which are parts of a surrounding body of cool metal, this added metal will cool while the surfaces themselves are held stationary in the position they originally occupied. The inevitable result is that the added metal will crack under the strain, or, if the weld is exceptionally strong, the main body of the work will be broken by the force of contraction. To overcome these difficulties is the second and most important reason for preheating and also for slow cooling following the completion of the weld.

There are many ways of securing this preheating. The work may be brought to a red heat in the forge if it is cast iron or steel; it may be heated in special ovens built for the purpose; it may be placed in a bed of charcoal while suitably supported; it may be heated by gas or gasoline preheating torches, and with very small work the outer flame of the welding torch automatically provides means to this end.

The temperature of the parts heated should be gradually raised in all cases, giving the entire mass of metal a chance to expand equally and to adjust itself to the strain imposed by the preheating. After the region around the weld has been brought to a proper temperature the opening to be filled is exposed so that the torch flame can reach it.

One of the commonest methods and one of the best for handling work of rather large size is to place the piece to be welded on a bed of fire brick and build a loose wall around it with other fire brick placed in rows, one on top of the other, with air spaces left between adjacent bricks in each row. The space between the brick wall and the work is filled with charcoal, which is lighted from below. The top opening of the temporary oven is then covered with asbestos and the fire kept until the work has been uniformly raised in temperature to the desired point.

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