Abstract: An arrangement for operating an arc furnace with two vessels for making steel. Enough liquid raw iron is added to account for 70% of the total starting metallurgicals. The supply of electricity to one of the vessels is discontinued but not to the other vessel. The injection of oxygen through a lance accompanied by the addition of sponge or coolant and lime, is carried out in one vessel while an electric-arc furnace phase is carried out in the other vessel, whereby additional sponge or coolant is melted with less oxygen and additional lime or coal is added. Electrodes are mounted on an arm and can be pivoted over either vessel as desired.