Abstract: For detecting leakage past a high pressure seal which seals a space in which a high pressure exists, there is arranged outside the high pressure seal a collection space for pressure medium which leaks into the space and a device is provided connected with the space to detect changes in the pressure or temperature therein and to produce a signal or to stop the press. The detecting device may be an insulated cable which seals the space on the side remote from the high pressure seal and which may be broken by pressure within the space, thereby interrupting an electrical circuit.

Abstract: A protection device for lines, bus bars, transformers and the like in electrical networks includes for each object a directional wave detector arrangement with one detector unit per phase for sensing current and voltage transients occurring in the object in case of faults in the network. Each wave detector unit includes directional detecting devices and a plurality of level detectors connected with an output for tripping signals and an output for blocking signals. One directional wave detector unit is arranged for each connection to an object which is to be protected and is connected through level detectors to the logic system which compares the output signal from the directional wave detector for the object and disconnects the object in response to a tripping signal from any of the directional wave detectors only if none of the wave detectors has emitted a blocking signal.

Abstract: A turbo-generator with a rotor winding includes a plurality of slots in which the rotor windings are inserted and a plurality of slot wedges, at least two slot wedges lying in each slot on the outside of the winding and being electrically connected with each other. A plurality of relatively thin pressure tubes of a deformable material such as copper are positioned in the slots between the wedges and the windings. Thereafter, the pressure tubes are supplied with a thermosetting resin through feed tubes, the resin being supplied at a sufficient pressure and in a sufficient amount to produce an expansion of the space within the tube by at least 50 per cent. The feed tube is then subjected to heat in a localized area, thus accelerating the curing of the resin in this area of the tube and forming a plug, after which the supply of pressure to the pressure tube is disconnected. After the resin in the pressure tube has hardened, the feed tube is removed.

Abstract: A hydraulic press includes a pressure cell which includes a diaphragm of flexible material with an opening therein surrounded by an annular bead. There are two disc-shaped attachment members for the diaphragm which form between them a first annular groove which fits the bead. The bead and one of the annular members have opposed annular recesses therein, which face a surface of the other annular member. These thus form an annular channel, in which are arranged two sealing rings, one fitting between the bead and one of the attachment members and the other fitting between the two attachment members.

Abstract: Unrefined steel is refined by the use of a refining slag in a furnace having two pressure-tightly interconnected, pressure-tightly covered upper and lower hearths having channeltype inductors for heating and stirring steel melts in the hearths, the refining being effected in the upper hearth only and which is of relatively small capacity and has its inductor tilted to effect vigorous melt flow. The refining is continued, batch after batch, with each batch transferred to the lower hearth which is of substantially larger capacity and where the refined steel can be held at a temperature lower than required for its refining, to obtain a volume of refined steel adequate for steel plant casting purposes. Gas pressure in the lower hearth maintains the melt level in the upper hearth as required during the refining, this gas pressure being lowered to transfer each batch of refined steel to the larger lower hearth, and then being increased again for the next refining operation.

Abstract: To reduce metal oxides to molten metal, an electrically non-conductive, annular hearth is used, the hearth being radially corrugated to form radial ridges and valleys. A circumferentially continuous coke bed forming a closed electric circuit, is formed on this bed and heated to incandescence by electric current passed through the bed in its circumferential direction, the current being either induced or applied directly. The oxides in particulated form are fed to this bed for reduction to molten metal, the metal collecting in the valleys of the hearth and thereby being prevented from forming a circumferentially continuous melt of higher electrical conductivity than the coke. Particulated coke and oxides can be fed continuously to the bed, the molten metal being then continuously tapped from the valleys of the hearth to thereby prevent the formation of a circumferentially continuous melt.

Abstract: An improved device for magnetically detecting and locating defects in metal bodies such as shafts, tubes, strips, sheets etc., in which a multiphase generator is used to generate a traveling field such as a rotating or linearly traveling field in the body being tested and in which means are provided to sense any assymetry in the resulting magnetic field resulting from eddy currents induced in the object such as to permit determining the location and nature of the fault from the electrical signals obtained.

Abstract: A tubular electrode contains a feeding tube forming an annular passage between its outside and the inside of the electrode. With the electrode forming a cathode, an arc is formed between it and a carbonaceous iron bath in an enclosed hearth having a gas outlet. Iron oxide material in flowable form is fed through the inner tube to the arc while a non-oxidizing gas is fed via the passage formed between the two tubes, to the arc. The carbonaceous iron bath is made the anode and the action of the current forms an upward bulge in the metal in the arc, gravitationally freeing the bath from any slag at the arc. In this way the iron oxide material is melt reduced, the iron component being continuously added to the bath which may be continuously tapped to provide a supply of crude iron.

Abstract: In a hydraulic press which includes a pressure cell with a diaphragm of flexible material which is intended to press a pad of flexible material against forming pieces in a working space below the pad, the diaphragm has an opening with an annular bead therearound. Two disc-like attachment members are provided, which form between them an annular groove which fits the bead of the diaphragm. Between the bead and one of the attachment members there is formed an annular groove within which is a sealing ring which engages between the bead and at least one of the annular members.

Abstract: In a motor-driven rail vehicle, an arrangement is provided for sensing oscillations in the drive system occurring in a predetermined frequency range, and to reduce the torque of the motor if the oscillation amplitude sensed thereby exceeds a predetermined threshold value.

Abstract: In an oil-filled apparatus, such as a transformer, having parts between which pressure is to be applied, such pressure is produced by providing between the parts bodies of an elastomer which absorbs the oil and expands as a result of such absorption. Such bodies may be used between windings and cores or as a seal between a transformer lid and a flange.

Abstract: A conservator system for transformers includes a conservator tank. The apparatus is filled with oil which is saturated with a non-combustible gas. The conservator tank is connected by conduits to the top and if suitable also to the bottom of the transformer tank, respectively. The top of the conservator tank is filled with free non-combustible gas. A bag of flexible material is arranged in the top of the conservator tank and the interior of this bag is connected to the atmosphere so that it separates the oil and the gas in the tank from the atmosphere.

Abstract: In a press for hydrostatic extrusion which has a prestressed outer supporting member and an inner tube or liner, the end surfaces of the inner tube are inwardly inclined towards its center with an inclination of at least 1:20, and the seal holders which take up forces operating on the seals have inclined end surfaces which make contact with the inclined end surface of the inner tube. The sealing arrangement includes a first sealing ring with a cylindrical inner surface which contacts the punch and the die respectively, and an end surface making contact with the support ring, and a second sealing ring with an outer cylindrical sealing surface which makes contact with the inner tube and an inclined end surface which makes contact with the inclined end surface of the support ring.

Abstract: A press for treatment of material includes a high pressure chamber formed of a vertical high pressure cylinder having end closures projecting into the cylinder and a press stand with a clear opening which is somewhat greater than the length of the high pressure chamber when the end closures are fully inserted. The high pressure cylinder is mounted on a carrying device which can move it into the clear opening of the press stand with gaps between the press stand and the end closures. One of the end closures is constituted by a piston slidable in the high pressure chamber. This piston has an annular portion which is slidable in an annular space formed at the end of the high pressure cylinder. Fluid under pressure can be supplied to the space on the side of the annular projection facing away from the high pressure cylinder to move the piston into the high pressure chamber and holding it there during movement of the high pressure chamber into the press stand, whereafter such pressure fluid can be released.

Abstract: A power factor correcting means for connection to an AC voltage network includes a transformer with high voltage terminals for connection to the network and low voltage terminals. A capacitor battery is provided for connection to the network, and a controllable inductive element is connected to the low voltage terminal of the transformer. The capacitor battery includes a first part connected to the high voltage terminal of the transformer, and a second part connected to the low voltage terminal of the transformer. The total rated power of the capacitor battery is substantially as great as the maximum reactive power of the inductive element, and the rated power of the second portion of the capacitor battery is between 0.3 and 0.7 times as the maximum reactive power of the inductive element.

Abstract: A load levelling system for connection to an alternating current network includes an electro-chemical direct current source and line-commutated controllable convertor means having DC terminals connected to the supply source and AC terminals for connection to the network. A continuously reactive power generating system composed of a fixed capacitor battery and a line-commutated reactive convertor is connected to the AC terminals. The convertor means may include a first convertor and a second convertor, the first convertor having a higher rated voltage than the second, with a control angle arrangement for the first convertor. The convertors are series-connected through their DC terminals and have a transformer connecting their AC terminals.

Abstract: A method for reducing iron oxide in a melt of iron by maintaining a reduction layer on the surface of the molten iron and passing the molten metal from the melt through vertical channels which communicate at the bottom of the metal melt an with a space at the top of the melt which is above that of the reduction layer so as to pass the melt including the oxide there through the reduction layer, the molten metal being lifted up through the channel by means of a gas lift pump action and heating the molten metal by inductive heating while it is flowing through the channel.

Abstract: For forced ageing of a commutator intended for a rotary electrical machine while the commutator is being rotated, heat is being supplied to it by a coil for generating a high frequency magnetic field arranged outside the commutator in such a way that the field is directed substantially perpendicular to the commutator surface, the coil being supplied with a current of a frequency of at least 1,000 Hz.

Abstract: In isostatic hot pressing of powder in a collapsible container, the powder is enclosed in a container which is provided with one or more evacuation openings, and a conical support is held in position adjacent the evacuation openings. A funnel-shaped body of sheet metal is secured above the support and the evacuation openings by welding its edge to the wall of the container. The body is evacuated through a suction tube connected to the funnel and the tube is sealed. Thereafter the container is subjected to heat and pressure, and the funnel-shaped member collapses into engagement with the conical support.

Abstract: A rail vehicle is carried by two-axled bogies pivoted to it, four shock absorbers only for damping the movements of the body of the vehicle are arranged between the body and each bogie; these are placed on both sides of the transverse and logitudinal axes of the bogie at a relatively great distance from the transverse axis and are arranged at an angle to the horizontal.