There are three basic welding methods: manual, semiautomatic and automatic.
Manual welding is the oldest method, and though its proportion of the total welding market diminishes yearly, it is still the most common. Here an operator takes an electrode, clamped in a hand-held electrode holder, and manually guides the electrode along the joint as the weld is made. Usually the electrode is consumable; as the tip is consumed, the operator manually adjusts the position of the electrode to maintain a constant arc length.
Semiautomatic welding is becoming the most popular welding method. The electrode is usually a long length of small-diameter bare wire, usually in coil form, which the welding operator manually positions and advances along the weld joint. The consumable electrode is normally motor-driven at a preselected speed through the nozzle of a hand-held welding gun or torch.
Automatic welding is very similar to semiautomatic welding, except that the electrode is automatically positioned and advanced along the prescribed weld joint. Either the work may advance below the welding head or the mechanized head may move along the weld joint.
Vocabulary
Сable кабель Еarth clamp заземление
Еlectrode электрод Holder электрододержатель
Transformator трансформатор Power network сеть электропитания
Сircuit breaker выключатель тока local exhaust зонт местной вытяжки
True or False?
1. Manual welding is the newest method.
2. A welder can use manual position during semiautomatic welding.
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3. Semiautomatic welding is the most popular welding method because the weld joint is accurate.
4. Semiautomatic welding is not the most popular welding method.
5. The welding operator manually adjusts the position of the electrode to
maintain a constant arc length.
Welding methods and descriptions.
1. manual 2. semiautomatic 3. automatic
a) the work may advance below the welding head or the mechanized head
b) the operator manually adjusts the position of the electrode to arc length
c) the oldest method
d) the electrode is usually a long length of small-diameter bare wire
e) the consumable electrode is normally motor-driven at a preselected speed
f) the electrode is automatically positioned and advanced along the prescribed weld joint.
Find in the text.
1) берёт электрод
2) зажимаемый в электрододержателе для ручного сварочного процесса
3) вручную проводить электродом по стыку
4) вручную регулировать положение электрода
5) поддерживать стабильную длину дуги
6) электрод большой длины с маленьким диаметром голой проволоки в форме катушки
7) плавящийся электрод механизируется на заданной скорости через сопло ручной сварочной горелки или сварочного пистолета
8) сварочная или механизированная головка
Read in the text.
1. …. is very similar to semiautomatic welding.
2. …. the electrode is consumable; as the tip is consumed.
3. …. of a hand-held welding gun or torch.
4. …. an operator takes an electrode.
5. …. it is still the most common.
6. Read the grammar rule and do grammar exercise.
Модальные глаголы и их эквиваленты (may, can, must)
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Переведите английские пословицы, обращая внимание на модальные глаголы. Подберите русские эквиваленты пословиц, где это возможно.
1. A man can do no more than he can.
2. Anyone who has to ask the price cannot afford it.
3. People who live in glass houses should not throw stones at their neighbours.
4. You must learn to walk before you can run.
5. He who falls today may rise tomorrow.
6. A bird may be known by its song.
7. He who laughs at crooked men should need to walk very straight.
8. Talk of the devil and he is to appear.
9. A tree must be bent while young.
10. The wind can’t be caught in a net.
А) После ненастья - солнышко. Не терт, не мят – не будет калач.
Б) Учи ребенка, пока мал. Куй железо, пока горячо.
В) За ветром в поле не угонишься.
Г) Выше головы не прыгнешь.
Д) Любой, кто вынужден спросить про цену, не может этого себе позволить.
Е) Птицу видно по полету.
Ж) Нет лучше шутки, как над собой.
З) Легок на помине.
И) Как аукнется, так и откликнется. Не рой другому яму – сам в нее попадешь.
К) Сперва «аз» да «буки», а потом науки.
Text 4
Metals.