разработка урока по иностранному языку Виды сварки


Lesson 1. Non-consumable Electrode Arc welding

Цели и задачи урока:

Познавательный аспект знакомство с понятиями:

С видами сварки

Газа сварка

электросварка

Органная сварка

Развивающий аспект – развитие мышления:

Воображение

способности к развитию и переключению внимания

К сравнению и сопоставления

Сопутствующая задача – развитие умения читать с целью извлечения детальной информации.

Речевой материал: gas-tungsten, semi-automatic, gas-metal arc

Ход урока

I. Организационный момент

Объявление целей и задач урока

II. Основная часть урока

Фонетическая обработка слова в транскрипции в режиме:

1. Прочитайте шепотом

2. Повторите за мной

3. Прочитайте партнёру

Vocabulary

1. Gastungsten сварка вольфрамовым электродом

2 . Inertинертный

3. Edgeкрай

4. Bare голый

5. Rateзд. скорость

6. Gasmetal arc аргонодуговая сварка

7. Considerablyзначительно, гораздо

Reading compression: Прочитайте текст и ответьте на вопросы:

Text B: «OTHER TYPES OF WELDING»

Non-consumable Electrode Arc welding

As non-consumable electrodes tungsten or carbon electrodes can be used. In gas-tungsten arc welding tungsten electrode is used in place of the metal electrode used in shielded metal-arc welding. A chemically inert gas, such as argon helium or carbon dioxide is used to shield the metal from oxidation. The heat from the arc formed between the electrode and the metal. Metal for the weld may be added by placing a bare wire in the arc or the point of the weld. This process can be used with nearly all metals and produces a higt-guality weld. However the rate of welding is considerably slower than in other processes. Cas-Metal Arc.

In gas-metal welding a bare electrode is shielded from the air by surrounding it with argon or carbon dioxide gas and sometimes by coating the electrode with flux. The electrode is fed into the electronic arc and melts off in droplets that enter the liquid metal of the weld seam Most metals can be joined by this process Submerged Arc.

Submerged-arc welding is similar to gas-metal arc welding but in this process no gas is used to shield the weld. Instead of that the arc and tip of the wire are submerged beneath a layer of granular fusible material that covers the weld seam. This process is also called electroslag welding. It is very efficient but can be used only with steels.

Resistance Welding

In resistance welding heat is obtained from the resistance of metal to the flow of an electric current. Electrodes are clamped on each side of the parts to be welded the parts are subjected to great pressure and a heavy current is applied for a short period of time. The point where two metals touch creates resistance to the flow of current. This resistance causes heat which melts the metals and creates the weld. Resistance welding is widely employed in many fields of sheet metal or wire manufacturing and is often used for welds made by automatic or semi-automatic machine especially in automobile industry.

Exercise 1.1Translate into English:

Вольфрамовый электрод

Инертный газ

Окисление

Высококачественный сварочный шов

Скорость сварки

Аргон, гелий, углекислый газ

Жидкий металл

Слой плавкого материала в виде гранул

Листовой металл

Полуавтоматические сварочные станки

Exercise 1.2. Translate into Russian:

1. In resistance welding heat is obtained from the resistance of metal to the flow of an electric current.

2. The heat from the arc melts the edges of the metal.

3. A bare electrode is shielded from the air by surrounding it with argon dioxide gas.

4. Submerges are welding is similar to gas-metal arc welding.

5. Electrodes are clamped on each side of the parts to be welded.

6. Resistance causes heat which melts the metals and creates the weld.

Exercise 1.3 Connecting words:

a) gas1) auto metric

b) weld2) are

c) semi3) beneath

d) carbon 4) seam

i) submerged5) metal

f) Liguid6) dioxide

j) sheet 7) tungsten

h) submergeol 8) metal

Exercise 1.4 Find the words in the text and try to guess their meanings. Translate in to Russian.

Carbon dioxide, liquid, layer,

resistance, sheet, granular,

semi – automatic, to submerge.

Exercise 1.5 Answer the questions:

What is the difference between the arc-welding and non-consumable electrode arc welding?

What are the disadvantages of the non-consumable electrode arc welding?

How is electrode protected from the air in gas-metal arc welding?

What is submerged arc welding?

What is the principle of resistance welding?

Where is semi-automatic welding employed?

III. Подведение итогов урока.

Домашнее задание: выучить топик.






See also:
Яндекс.Метрика