 oscar kjellberg (21 september 1870 â 5 july 1931) was a swedish inventor and industrialist. founder of esab, in 1904, and kjellberg finsterwalde, in 1922. he invented the coated electrode used in manual metal arc welding (swedish patent: 27152, june 29, 1907), by dipping a bare iron wire in a thick mixture of carbonates and silicates. the purpose of the coating is to protect the molten metal from oxygen and nitrogen present in the atmosphere. his pioneering of covered electrode development paved the road during the next twenty years in the research of reliable flux coated electrodes.  == external links == *esab - official site *kjellberg finsterwalde - company founded by oscar kjellberg in 1922  
1870_births 1931_deaths Swedish_inventors