The invention of Soderberg electrode

In 1919, Elkem patented Soderberg electrode, a self-baking electrode which revolutionized the smelting industry. The new Søderberg technology, allowed for a non-stop continuous smelting in submerged arc furnaces.

The small furnaces at the time, depended on graphite electrodes and prebaked carbon electrodes, which could only be produced in limited sizes. After the invention of a self-baking electrode, it was no longer required to stop furnaces for the removal and assembly of electrode pieces intermittently, which improved efficiency of smelting operations significantly.

The invention was named after Carl Wilhelm Søderberg (1876 – 1955), an electrical engineer who first had the idea of a self-baking electrode. Although two of his colleagues, Matthias Ø Sem and Jens Westley, also contributed significantly towards the initial development of this technology. 

Continues improvments

New furnace designs emerged and Søderberg electrode underwent a series of technical improvements. Elkem was able to sell a Søderberg electrode system that became the established means of electric smelting of calcium carbide, pig iron and ferroalloys such as ferrosilicon and ferromanganese.

By 1926, 66 plants worldwide had installed 164 submerged arc furnaces, equipped with Søderberg electrodes. Eventually Elkem supplied the technology for the installation of more than 400 furnaces worldwide. The largest diameter of a Søderberg electrode in operation today, is 2 100 mm.

A world leading player

The development of Søderberg electrode paved the foundation for growth in ferroalloys industry. Today, Elkem is a world leading player within the ferrosilicon and silicon industries. Further development of carbon products has been achieved through continuous improvement and testing of new products under controlled conditions.

Our products are produced and shipped from our plants in Brazil, Norway, South Africa and China.