Abstract: A method for the optimum regulation of the electrodes of a three-phase electric arc furnace wherein each electrode has an associated arc voltage regulator which receives the associated arc voltage as its actual value and a desired arc voltage value as its reference value; and wherein, to form the desired arc voltage value, during each halfwave, a voltage porportional to the actual arc current and a limit value, which corresponds to the desired arc length, are provided, and the smaller momentary value, with respect to magnitude, of the current proportional voltage and of the limit value is always fed to the arc voltage regulator as the desired arc voltage value.

Abstract: A method and apparatus for regulating an arc discharge furnace having a lining, a plurality of electrodes disposed above a bath of conductive material, an adjustable transformer for applying to each electrode a voltage which causes an arc current proportional to the applied transformer voltage to flow between the electrode and the bath, a device for varying the voltage applied by the transformer to each electrode, and a device for varying the vertical spacing between each electrode and the bath. Desired values for a maximum of two of the following parameters are selected: the voltage of the arc current produced by one electrode; the arc current produced by the one electrode; the power of the arc produced by the one electrode; a parameter which is proportional to the wear caused to the furnace lining by the arc produced by the one electrode; and a correcting variable for the voltage applied to the one electrode by the transformer.

Abstract: A method and apparatus for electrically balancing the phases of a three phase arc furnace, the furnace having a vessel containing a molten bath, three electrodes above the bath, and a transformer arrangement composed of three phases, each phase including a winding, the transformer arrangement being connected to the electrode so that each electrode conducts an arc current proportional to the voltage across the winding of a respective phase, by the steps of: matching the voltages between the electrodes and the bath to one another by adjusting the spacing between at least one electrode and the bath; and establishing symmetry among the arc currents by: varying the voltage across at least one phase winding by a selected increment; measuring the arc current amplitude in the electrode associated with the at least one phase winding after each variation step; and repeating the steps of varying and measuring until the differences between the arc current amplitudes of the three electrodes are less than a given value.

Abstract: In order to assure a high arc current and a high arc power with simultaneous reduction of flicker voltages, at least two juxtaposed electrodes, each having the same distance from the vertical axis of the furnace and the same electrical potential, are connected to each phase of an electric arc furnace, which is preferably a three-phase electric arc furnace. Preferably circular electrodes are employed which are conductively connected together at least in the vicinity of the electric arc.

Abstract: An electrode and conductor arrangement for a three-phase electric arc furnace supplied with power from a transformer, including three electrodes which extend downwardly into the furnace, and a plurality of current conducting paths each composed of a rigid conductor, which is conductively connected to a respective electrode and a flexible conductor connected in series between the rigid conductor and the transformer, the rigid conductors extending parallel to one another, the electrodes being spaced from one another in the horizontal direction transverse to the longitudinal axes of the rigid conductors, in which the conducting paths associated with the center electrode are spaced a minimum distance, in the horizontal direction transverse to the longitudinal axes of the rigid conductors, from the conducting paths associated with each of the outer electrodes, there are only two conducting paths, spaced vertically apart, connected to each outer electrode, the vertical spacing between the two conducting paths assoc

Abstract: An electrically driven linear vibrator has swing drive for vibrating troughs, jarring tables or the like comprises a stator with an exciter winding, an armature guided for linear movement in a direction transverse to the field produced by the stator and a pair of oppositely acting return springs forming together a swing drive, the vibration of which may be used to drive a device connected to the vibrator. The return springs may be constituted by metal springs, gas springs or a combination of both. The swing drive may be constructed as single-acting or double-acting drives. A diode may be connected with the electrical conductors leading to exciter winding so that at a line frequency of 50 Hz, an oscillation frequency of 100 Hz, 50 Hz or 25 Hz may be obtained. The vibrator may also be provided with a piston blower for cooling the windings of the stator.