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What parts of speech do the following words belong to? Translate these words into Russian.
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Useful, fire, experience, difference, ease, heating, fuse, controllable, process, practice.
Find in the dictionary all possible meanings of these words. Use them in your own sentences.
Bit, flow, course, range, stream, fine, turn, power, work, plate.
5. Point out which of these sentences do not contain information from the text. Translate these sentences into Russian:
Gas Metal-Arc Welding is a relatively simple, versatile, and economical welding apparatus to use.
2. A high voltage arc is used to superheat and ionize a stream of air to the "plasma" state.
3. The stream of plasma makes a rapid, clean, narrow cut with minimal heating of the work piece.
Electroslag Welding deposits the weld metal into the weld cavity between the two plates to be joined.
With the right bits, rod, and technique, you can weld almost anything.
6. Deoxidizers present in the electrode can completely prevent oxidation in the weld puddle, making multiple weld layers possible at the joint.
7. TIG is a high frequency AC arc process which uses a tungsten electrode shielded by an inert gas to create a fine, controllable torch.
Overheating of some types of work, harder to control quality of some processes.
Read and translate the text.
Text B
Aluminium
The weldability of aluminum alloys varies significantly, depending on the chemical composition of the alloy used. Aluminum alloys are susceptible to hot cracking, and to combat the problem, welders increase the welding speed to lower the heat input. Preheating reduces the temperature gradient across the weld zone and thus helps reduce hot cracking, but it can reduce the mechanical properties of the base material and should not be used when the base material is restrained. The design of the joint can be changed as well, and a more compatible filler alloy can be selected to decrease the likelihood of hot cracking. Aluminum alloys should also be cleaned prior to welding, with the goal of removing all oxides, oils, and loose particles from the surface to be welded. This is especially important because of an aluminum weld's susceptibility to porosity due to hydrogen and dross due to oxygen.
UNIT 3
Read and translate the text.
Text A
Gas Metal-Arc Welding
Gas Metal-Arc Welding (GMAW), also called Metal Inert Gas (MIG) welding, shields the weld zone with an external gas such as argon, helium, carbon dioxide, or gas mixtures. Deoxidizers present in the electrode can completely prevent oxidation in the weld puddle, making multiple weld layers possible at the joint.
GMAW is a relatively simple, versatile, and economical welding apparatus to use. This is due to the factor of 2 welding productivity over SMAW processes. In addition, the temperatures involved in GMAW are relatively low and are therefore suitable for thin sheet and sections less than ¼ inch.
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GMAW may be easily automated, and lends itself readily to robotic methods. It has virtually replaced SMAW in present-day welding operations in manufacturing plants.
Electroslag Welding
Electroslag Welding (ESW) deposits the weld metal into the weld cavity between the two plates to be joined. This space is enclosed by water cooled copper dams or shoes to prevent molten slag from running off. The weld metal is produced from a filler wire that forms an initial arc with the workpiece until a sufficient pool of liquid metal is formed to use the electrical resistance of the molten slag.
This process requires special equipment used primarily for horizontal welds of very large plates up to 91,44 centimeters or more by welding them in one pass as in large machinery and nuclear reactor vessels.
There are also variations of ESW where shielding is provided by an appropriate gas and a continuous arc is used to provide weld metal. These are termed Electrogas Welding or EGW machines.
Read and learn the following words and expressions:
| carbon dioxide weld puddle versatile to lend oneself Electroslag Welding (ESW) cavity filler wire molten slag appropriate machinery relatively sufficient suitable | - углекислый газ - сварочная ванна - универсальный - применяться - электрошлаковая сварка - полость - присадочная проволока - расплавленный шлак, - подходящий, соответствующий - механизм - относительно - достаточный; - подходящий |
1. Answer the following questions:
1. What are the most essential features of Gas Metal-Arc Welding? In 3-4 sentences describe this process.
2. What do you know about Electroslag Welding?
Give the summary of the text.
Fill in prepositions if necessary.
1. Deoxidizers present_______the electrode can completely prevent oxidation_______the weld puddle, making multiple weld layers possible at the joint.
2. _______addition, the temperatures involved in GMAW are relatively low.
3. It has virtually replaced SMAW_______present-day welding operations in manufacturing plants.
4. Electroslag Welding deposits the weld metal______the weld cavity between the two plates to be joined.
5. The weld metal is produced_______a filler wire that forms an initial arc with the workpiece.
6. There are also variations of ESW where shielding is provided_______an appropriate gas.
4. Point out which of these sentences do not contain information from the text. Translate these sentences into Russian:
1. Electroslag Welding (ESW) deposits the weld metal into the weld cavity between the two plates to be joined.
2. In addition, the temperatures involved in GMAW are relatively low and are therefore suitable for thin sheet and sections less than ¼ inch.
3. The process utilized an electron gun similar to that used in an X-ray tube.
4. GMAW may be easily automated, and lends itself readily to robotic methods.
5. Mechanical pumps can produce vacuums to the medium pressure level.
6. Deoxidizers present in the electrode can completely prevent oxidation in the weld puddle, making multiple weld layers possible at the joint.
7. Recent advances in equipment allow the work chamber to operate at a medium vacuum or pressure.
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8. The weld metal is produced from a filler wire that forms an initial arc with the workpiece until a sufficient pool of liquid metal is formed to use the electrical resistance of the molten slag.
9. It has virtually replaced SMAW in present-day welding operations in manufacturing plants.
10. Virtually all of the kinetic energy-the energy of motion-of the electrons is transformed into heat upon impact.
Translate the following words paying attention to their suffixes.
External, mixtures, completely, layer, relatively, addition, automated, readily, operation, produced, resistance, primarily.
Find in the dictionary all possible meanings of these words. Use them in your own sentences.
Complete, mixture, present, involve, suitable, section, plant, shoe, arc, pass, use, initial, space, provide, machine.
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