Добавил:
Upload Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
MU_dlya_SM_1_chast.doc
Скачиваний:
39
Добавлен:
07.02.2016
Размер:
325.12 Кб
Скачать

Welding

Oxy – fuel welding

Arc welding

Stick welding

Not use an arc; use a flame; problems in welding; ways of protection; flux gas; shielding gas; using in machine building.

V Oral practice

Ex. 12. Give information about welding and the types of welding using the table from ex. 11.

Ex. 13. Make up the dialogue:

You are a student of the 2 course and you have a task to write down a report on the subject “ Welding and its using” You are going to visit a plant and have a meeting with a fitter of the shop. Ask questions in order to get the information about:

  • The most common types of welding;

  • The necessity to protect hot metal;

  • Two main ways to shield an arc welding.

  • Some kinds of welding not using an electric arc.

- Ways of protection during welding.

VI. Reading and comprehension

Ex. 14. Read and translate the text without a dictionary for 5 minutes and answer the questions after the text:

Text B

Arc welding

Any kind of welding that uses an electric arc is a kind of arc welding. There are different kinds of arc welding too— shielded metal arc welding (SMAW) is a common type. Sometimes SMAW is called stick welding. Another common one is gas metal arc welding (GMAW). It is sometimes called wire welding or metal inert gas welding (MIG welding). Another type of arc welding that is less common is gas tungsten arc welding (also known as tungsten inert gas welding or TIG welding). Before there were many kinds of arc welding, SMAW was called just 'arc welding'. Sometimes it is still called that today, but it's better to call it by it's real name instead. Arc welding heats metals by making an electric arc between the piece of metal and something called an electrode. An electrode is the part of the welder that the arc touches.

Sometimes the electrode is used up by the welding, sometimes it is not. In SMAW, GMAW, and some other kinds, the electrode is used up. The electrode is made of the same kind of metal that is being welded, and melts into the weld and becomes part of it. Because it is used up, it must constantly be fed into the weld. In SMAW, the electrode is a rod of metal with flux on it. There is more information on flux further down. The person doing the weld feeds the rod into the weld. In GMAW, the electrode is a thin wire that might be as thin as 0.635 millimeters. Really big welds might use a 4 millimeter electrode, but the biggest common electrode size is around 2 millimeters. The welding machine has a motor in it that pushes this wire into the weld.

  1. What can be called a kind of arc welding?

  2. What is stick welding?

  3. What is an electrode?

  4. What do you know about welding machine?

Supplementary reading. Texts for written translation with a dictionary

Read the texts and translate them in writing. Use a dictionary

Соседние файлы в предмете [НЕСОРТИРОВАННОЕ]