История возникновения сварочного производства

Read and remember:

1. Read the following Text:

WELDING

1. Welding is a process of joining together metallic parts by heating the place of contact to the fusion state.2. Welding processes are classified according to the source of energy employed for heating, the metals and the state of the metal at the place of welding.3. There are different types of welding such as hammer welding, thermit welding, electric arc welding, gas welding, etc.4. Hammer welding is a process in which two heated metal parts are joined and fused together by force from a power hammer.5. Thermit welding is a process consisting of a chemical reaction. 6. It is used in repairing large sections such as rails, frames, etc.7. Resistance welding process forms a whole group consisting of many types of welding such as spot welding, butt welding and others.8. In arc welding the workpieces are not melted by a flame. 9. They are melted by an electric arc. In order to create the arc, a powerful electric current must be provided. 10. The current must be at least 60 A, otherwise the arc will not create enough heat.11. In gas welding, it is necessary to use a mixture of two gases. 12. To create a hot flame, a combustible gas must be mixed with oxygen.13. Gas welding is normally used to join steel to steel.

Translate the Text in writing.

Put 7 general questions to the Text.

Retell the main idea from the Text.

Home Test

Ex.1 Match the sides:

Ex.2 Choose the right variant.

VOCABULARY

v неразъемное соединение – a solid bond;

v технология – process, technology;

v угольный электрод – carbon electrode;

v точечная сварка – spot welding;

v роликовая сварка – roller welding;

v контактная сварка – resistance welding;

v припой – solder;

v переменный ток – alternating current;

v постоянный ток – direct current;

v легированный – alloyed;

v добавка – additive;

v увеличиваться / уменшаться (о токе) – to amplify / to attenuate.

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Как выполняются сварочные процессы

Text 1.

Welding.

1. Read and translate the text.

Welding is a process when metal parts are joined together by the application of heat, pressure, or a combination of both. The processes of welding can be divided into two main groups:

•pressure welding, when the weld is achieved by pressure and

•heat welding, when the weld is achieved by heat. Heat welding is the most common welding process used today.

Nowadays welding is used instead of bolting and riveting in the construction of many types of structures, including bridges, buildings, and ships. It is also a basic process in the manufacture of machinery and in the motor and aircraft industries. It is necessary almost in all productions where metals are used.

The welding process depends greatly on the properties of the metals, the purpose of their application and the available equipment. Welding processes are classified according to the sources of heat and pressure used: gas welding, arc welding, and resistance welding. Other joining processes are laser welding, and electron-beam welding.

Vocabulary

pressure welding сварка давлением

heat welding сварка нагревом

instead вместо, взамен

bolting скрепление болтами

riveting клепка

basic основной

to manufacture изготовлять

to depend зависеть от

purpose цель

gas welding газосварка

arc welding электродуговая сварка

resistance welding контактная сварка

laser welding лазерная сварка

electron-beam welding электронно-лучевая сварка

Answer the questions.

1. How can a process of welding be defined?

2. What are the two main groups of processes of welding?

3. How can we join metal parts together?

4. What is welding used for nowadays?

5. Where is welding necessary?

6. What do the welding processes of today include?

Find in the text.

1. Сегодня сварка используется вместо соединения болтами.

2. Сварочный процесс в основном зависит от свойств металла.

3. Она необходима почти во всех производствах, где используется металл.

4. Сварка нагреванием – самый распространенный процесс сварки сегодня.

5. Это основной процесс в машиностроении.