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. In 1904 Oscar Kjellberg in Sweden, who started ESAB, invented and patented the covered electrode. This electric welding process made strong welds of excellent quality.
During the 1920s, major advances were made in welding technology, including the introduction of automatic welding in 1920, in which electrode wire was fed continuously.
Shielding gas became a subject receiving much attention, as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems, and the solutions that developed included the use of hydrogen, argon, and helium as welding atmospheres.
2. 4 Working with the text.
Find equivalents for the following words combinations i桴整瑸ഺ
Угольный электрод, электрод с покрытием, защитный газ, торговое
судоходство, открытая печь, военный самолет, источник тепла, признавать преимущества электродуговой сварки.
True or false?
ar in Delhi, India.
2. The discovery of acetylene made it possible to achieve higher heatingtemperatures.
3. The first electrode used in welding was a covered one.
4. The British Prime Minister Winston Churchill was a famous welder.
подведение итогов урока
3. 2 Marks of the lesson/оценивание
3. 3 Home task – выучить новые слова (терминология сварочного дела, см 2. 2. )
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