Wordlist. pressure welding сварка давлением

pressure welding сварка давлением

arc welding электродуговая сварка

resistance welding контактная сварка

laser welding лазерная сварка

electron-beam welding электронно-лучевая сварка

to shield заслонять, защищать

bolting скрепление болтами

riveting клепка

Questions

1. What is welding? 2. What are the two main groups of welding? 3. Where is welding necessary? 4. What do the welding process of today include? 5. What are the principles of gas and arc welding?

Контрольная работа № 3 Вариант № 4

I. Перепишите сложные существительные, определите в них основное слово; переведите на
русский язык.

a railway, a seaman, a postman, a classmate, a schoolboy, a shop-assistant

II. Образуйте причастие I от следующих глаголов, переведите словосочетания на русский язык

(to pass by) people - passing by people, a girl (to write on the blackboard), the sun (to rise), people (to gather), a (to paint) man, a (to work) crane

III. Употребите возвратные местоимения

1. He wants to build a house... .2. She cleaned the flat.... 3. You will finish the work.... 4. Look at... in the mirror. 5. We shall tell her everything....6. Help...!

IV. Образуйте от глаголов причастие II, переведите словосочетания на русский язык.

an (to establish) institution - an established institution, goods (to sell), parts (to machine), electrodes (to use), heal (to obtain), operations (to mechanize)

V. Переведите предложения, обращая внимание на видовременные формы страдательного

залога.

1. Keys were lost yesterday. 2. The letter will be sent tomorrow. 3. Is she often asked? 4. Your question will be answered tomorrow. 5. 1 was offered an interesting job. 6. The dish is made with good taste.

VI. Перепишите предложения, обратите внимание на придаточные предложения; переведите
их на русский язык.

1. Не goes out when the weather will get warmer. 2. If he had known the timetable he wouldn't have missed the train. 3. It would be better if you learned to drive a car. 4. I would have sent a letter to you if I had known your address. 5. If 1 were you I wouldn't buy tickets beforehand. 6. If I have spare time, we shall go to dance.

1VII, Прочитайте текст, переведите его письменно и ответьте на вопросы после текста.

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 the 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 machines especially in automobile industry.

Non-consumable Electrode Arc welding

As a non-consumable electrodes tungsten or carbon electrodes can be used. In gas-tungsten arc welding a 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 melts the edges of 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 high-quality weld. However, the rate of welding is considerably slower than in other process.

Shielded Metal Arc welding

In shielded metal-arc welding, a metallic electrode, which conducts electricity, is coated with flux and connected to a source of electric current. The metal to be welded is connected to the other end of the same source of current. Touching the tip of the electrode to the metal and then drawing it away forms an electric arc. The intense heat of the arc melts both parts to be welded and the point of the metal electrode, which supplies filler metal for the weld. This process is used mainly for welding steels.

Дата добавления: 2015-07-20