Read and translate the text.

3. Answer the following questions:

1. What metals is plasma welding used for?

2. What machines for plasma welding are available?

3. What are the important properties of plasma welding?

4. What does the modern electronics allow?

5. What can surfacing be used for?

6. What materials can be used as the coating ones?

7. Where does plasma surfacing gain wide acceptance?

4. Are the following statements about the text true or false? Why?

1. Plasma welding provides the highest effect when used for joining metals with low thermal conductivity.

2. The straight polarity plasma arc can weld copper up to 100mm. thick in a single pass.

3. Strength characteristics of the weld metal containing tungsten inclusions are very high.

4. The important property of microplasma welding is low degree of constriction of the arc.

5. Owing to the maximum penetration of the base metal and its maximum dilution with the deposited metal, the process of plasma surfacing provides the preset properties of the metal even in the first of the deposited layers.

6. Plasma surfacing is not used in machine- building.

5. Continue the following sentences:

1. Plasma welding allows avoidance of …

2. The usage of this welding method leads to…

3. Modern electronics allows…

4. Plasma surfacing gains wide acceptance in …

6. Fill in the gaps using the following words and word-combinations:

Constriction, straight polarity, reverse polarity, straight polarity, single pass, dilution, penetration, single pass.

1. The … … plasma arc can weld copper up to 50 mm. thick in a … ….

2. The important property of microplasma welding is a high degree of … of the arc.

3. Plasma surfacing can be performed at a direct current of … or … polarity.

4. Owing to minimum … of the base metal and its minimum … with the deposited metal the plasma surfacing provides the preset properties in the first of the deposited layers.

5. Plasma arc can weld copper up to 50 mm. thick in a … … without groove preparation.

Find in the text the sentences with Passive Voice.

Make 10 questions to the text.

9. Choose the correct verb form in the following sentences:

1. Plasma welding (provides, has provided) the highest effect when used for joining metals.

2. Plasma welding (allows, allowed) avoidance of preheating.

3. The important property of plasma welding (is, are) a high degree of constriction of the arc.

4. Plasma surfacing (can be performed, can perform) at a direct current or reverse or straight polarity.

5. Plasma surfacing (gains, has been gained) wide acceptance.

Retell the text.

TEXT C

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