Abstract: Connections between sections having thread sockets at the end face of carbon or graphite electrode by a double-conical threaded nipple screwed into the sockets in which the cone halves of the nipple are different in height.

Abstract: An electrode for arc furnaces, comprising a metallic water-cooled upper section and a consumable, replaceable lower section, interconnected by means of a threaded nipple or the like. At least one light-receiving element is positioned in a zone associated with the interconnection of the cooled metal shaft and the consumable section. A light signal falling on the light-receiving element where the consumable section is in absence, is passed in a suitable manner via a light wave guide to a furnace control which activates a safety system.

Abstract: A graphite nipple projecting from one end of a graphite electrode portion of the type used in an electric furnace has a supporting face for receiving a non-graphite portion of a clamping device in shape-locking engagement for holding the electrode for use. It also has a conventional screw-thread surface for joining the nipple to another electrode portion for extending the electrode. The supporting face does not alter the conventional screw-thread surface arrangement for joining electrode portions so that specially-shaped and thus costly electrode-supporting nipples are not required in addition to the conventionally-shaped nipples for joining electrode portions, and a graphite screw-thread does not have to be unscrewed for the same, which unscrewing frequently broke the nipple or electrode portion.

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: An apparatus for replenishing electrodes in an arc furnace or the like. The apparatus threadedly attaches a replenishment electrode section to a previously installed, presently working electrode section without interrupting the operation of the furnace. The electrode sections are provided with mating terminal threaded portions which are engaged by simultaneousy lowering and rotating the replenishment electrode section. By lowering the replenishment electrode at a faster rate than the lead of the electrode threads and accommodating relative vertical movement of the electrodes, it is not necessary to precisely match the lowering speed of the replenishment electrode with the threads of the electrode. A novel screw-driven, electrically insulated, telescopic drive train is employed for this purpose. The replenishment electrode is carried by a plurality of peripherally spaced wedges actuated independently of the drive train to retain and release the electrode.

Abstract: An apparatus for accurately aligning a replacement electrode with a working electrode. The replacement electrode is suspended from a trolley movable in two directions in a rectilinear pattern. The trolley is moved initially in a first direction into general transverse alignment with the working electrode position, then displaced in a second direction against a fixed stop to overlie the desired electrode position. The trolley is adjusted finally in the first direction during its travel toward the fixed stop by contacting a mast on the trolley with a fixed guide adjacent the stop.

Abstract: Apparatus for disconnecting a residual portion of a consumed graphite electrode from a permanent electrode which has been lifted out of an electric furnace and which may still be hot, and for connecting a fresh graphite electrode portion to the permanent electrode, comprises a housing for surrounding the electrode assembly in the region of a screw nipple on the permanent electrode. Disposed in the upper region of the housing is an upper clamping means for holding the permanent electrode, while disposed in the lower region of the housing is a lower clamping means which can produce a screwing movement for unscrewing and screwing on the graphite electrode portion. The housing is of a double-walled construction to provide for water cooling thereof.

Abstract: The proper assembly of electrode sections is facilitated by placing orientation match-marks on the electrode ends, which marks are lined up at the time of the assembly. Placing of the marks is done with marking gauges and the location is predetermined with reference to the pitch of the socket threads.