Abstract: A device for arc welding having one or more fusible electrodes (15) which are in each case supplied from an alternating-current source (14) having a falling characteristic. The feed rate of the electrode (15) is regulated for constant arc length as a function of the arc voltage. Via a further regulator (37), the deposition efficiency is regulated by supplying the regulator (37) with the feed rate as actual value and changing the welding-current intensity as a function of this value. The change in welding-current intensity leads to an increase or decrease in arc length which, in turn, is compensated via the first regulator by changing the feed rate.

Abstract: A welding process for joining aluminum materials in a horizontal welding position, without preheating, this process being highly economical and characterized by minimal environmental pollution, good strength and toughness of the welded joint, in which process the arc, as in submerged arc welding of steel plates, is covered by a flux layer and burns in a closed cavity, this process being realized by the use of a flux having a flux composition of 20-70% potassium chloride (KCl), 20-70% of an alkaline earth metal chloride, preferably calcium chloride and/or magnesium chloride (CaCl.sub.2 and/or MgCl.sub.2), 1-20% of calcium fluoride (CaF.sub.2) and preferably 1-15% of a substance capable of lowering the melting point and/or releasing gas.