Abstract: A direct current arc furnace has at least one anode movable into the furnace interior and at least one cathode also movable from above into the furnace interior, between which cathode and the inserted material or the melt an arc is produced. The anode contains a cooling system in its interior having a controller which cools at least the immersion region of the anode to a temperature which is lower than the temperature of the melt.This furnace device and the anode are utilized in methods for melting and heating of materials with advantage, at least the immersion region of the anode being maintained at a temperature which lies below the temperature of the melt.

Abstract: In an electrode for electric arc furnaces, having a water-cooled metallic electrode holder and a consumable section connected to the electrode holder by means of a threaded nipple, the electrode holder having a protective jacket made up of rings. A disc positioned between the consumble section and the electrode holder which, in the event of a fracture of the consumable section, remains attached to the electrode holder for protection against electric arc strike.

Abstract: The invention concerns an electrode for arc furnaces, especially for electrosteel production, comprising a metallic liquid-cooled upper shaft (1) and an exchangeable lower active portion (2) of self-consuming material, particularly graphite, whereby a securing means is provided which is electrically insulated against the current-conducting components (11) of the shaft (1) and said securing means detachably connects the shaft (1) with the active portion (2) as well as holding the contact surfaces of the active portion (23) pressed against the contact surfaces (14) of the current-conducting components (11) of said shaft.

Abstract: Electrodes for arc furnaces comprising a top portion (5) of metal and a replaceable bottom portion (6) of material which is only slowly consumable, being substantially cylindrical shape and the portions being interconnected by means of a screw nipple (1) or the like and the top portion has a liquid cooling device with a header duct (2) and a return duct (3) and the top portion (5) is advantageously protected in the bottom region thereof by means of an insulating coating of high temperature stability representing a detachably surmountable moulding. An electrically conductive intermediate layer of high temperature stability can be provided between the insulating moulding and the top portion. The electrodes are only slightly trouble prone, have emergency operating properties, have a high mechanical stressability and are easy to repair.

Abstract: An electrode for arc furnaces comprising a top portion of metal and a replaceable bottom portion of a material which, when appropriate, is only slowly consumed having a substantially cylindrical shape and being joined each to the other by a screwmounting, for example by means of a screw nipple or the like. The top portion includes a liquid cooling device or means with a header and a return duct, and an insulating coating of high temperature stability. An inner part and an outer part of the top portion are constructed so as to be detachable each from the other. The inner part extends substantially adjacent the screw nipple and at least a portion of the inner part is provided with an insulating coating of high temperature stability, which represents a loosely surmounted moulding.

Abstract: Electrode for arc furnaces, more particularly for electrosteel production, also using scrap, comprising a detachable top portion (5) of metal and a replaceable bottom portion (6) of material which is consumed, where appropriate only slowly, having substantially cylindrical shape and being interconnected by a screw nipple (1) or the like and the top portion has a liquid cooling device with a header duct (2) and a return duct (3) and an inner part (16) and an outer part (17) of the top portion are constructed so as to be detachable from each other, so that the inner part (16) contains the liquid conducting chamber with header duct and return duct and the outer part (17) surrounds only a portion of the inner part (16). The electrodes have a reliable coolant conducting system, are easy to maintain and can be simply repaired in the event of mechanical damage while minimizing electrode down times.