Exercises

1. Learn the following words and word combinations:

conventional -традиційний

density -густина

deflection -відхилення

to divert -відхиляти

seam -стик

to vaporize -випаровуватися

to dissipate -розсіюватися

vapor channel -паровий канал

to penetrate -проникати

shield -щит

TIG -зварювання вольфрамовим електродом

в інертному газі

MAG -зварювання металевим електродом

в середовищі захисного газу

heat conduction welding -теплопровідне зварювання

deep welding -глибоке зварювання

2. Read and translate the text.

3. Answer the following questions:

1. What is the principle of laser welding?

2. What conventional welding techniques do you know?

3. What creates the energy in laser welding process?

4. In what way are the work pieces positioned?

5. What is formed in the material under the pressure?

6. What is the shield gas protecting the welding seam from?

7. What are the two laser welding techniques?

4. Decide, whether the statements below are true or false. Why?

1. There are few welding techniques nowadays.

2. The laser creates the energy that is necessary for the welding process.

3. Welding is the process of separating two like metal pieces.

4. The laser welding head moves across the joint over the work piece.

5. The keyhole penetrates a few millimeters deep into the material.

6. The joined material cools off and the cast solidifies.

7. The welding seam is not usually protected from reaction with air by a shield gas.

5. Put all possible questions to the sentences.

1. Today there are numerous welding techniques for every special field.

2. The laser creates the laser radiation and the energy for the welding process.

3. The enormous energy density of the laser beam in focus makes the material melt and vaporize.

4. The principle of laser welding is to create laser radiation and with it the energy, that is necessary for the welding process.

5. There are numerous techniques just for welding metals.

6. Other work gases can aid and control welding process.

6. Choose the correct definition to the word:

1.Welding

1. process of heating metals

2. process of joining metals

3. process of solidifying metals

2.Vapor

1. state of substance

2. state of mind

3. chaotic state

3. Seam

1. the place of interest

2. the place of enlargement

3. the place of connection

7. Fill in the gaps with a proper article.

1. .. principle of laser welding is to create laser radiation and with it ..... energy, that is necessary for .... welding process.

2. This energy is lead by .... deflection mirror or .... focusing device, to where it should have its effect, to .... joint of ..... work pieces.

3. ..... pressure of .... dissipating metal vapor can become so high, that .... vapor channel forms in ....material.

4. ....welding seam is usually protected from reaction with .... air by .... shield gas during ..... machining.

8. Complete the following sentences:

1. .................just for welding metals.

2. The principle of laser welding is.....

3. The pressure of dissipating metal vapor can become so high that.......

4. When the laser welding head moves over the workpiece.........

5. When welding with a laser.........

9. Give the three forms of the following verbs:

To call, to be, to reach, to have, to fix, to make, to become, to penetrate, to protect, to mix.

10. Communicative situations:

1. Make up a dialogue on the topic “Principle of laser welding”

2. Discuss the advantages of laser welding over other conventional welding techniques with your fellow students.

11. Retell the text.