Abstract: A method and apparatus for use with a measuring and/or control device having at least one sensor based on eddy current induction and movable over a test piece and supplied with at least two carrier frequency signals. A determination is made on one of the carrier frequency signals with respect to those signal changes obtained at the transistion from measuring against the test piece to measuring against essentially empty space. When such signal changes occur an edge signal is generated which indicates that the measuring and/or control device has passed over an edge of the test piece.

Abstract: An arrangement for distributing a cable assemblage between a stationary part and a part which is arranged for limited rotation relative to the stationary part, the cable assemblage comprising at least one power cable and at least one signal transmission cable. The arrangement includes a centrally located tubular element mounted on the stationary part and a housing which surrounds the tubular element and which is connected to the rotatable part. The signal transmission cable extends axially through the tubular element and is folded or deflected through about 90.degree., and extends out through an opening provided in the element and is then loosely wound helically for a number of turns around the outer surface of the tubular element. The cable then extends out through an opening in the surrounding housing and is again folded or deflected through 90.degree., so as to extend substantially axially along the outer surface of the housing.

Abstract: The invention relates to a power plant for combustion of a fuel, for example carbon, in a combustion chamber (2) in a bed (10) of fluidized particulate material, primarily a PFBC power plant. The plant includes a multi-stage steam turbine (13) and an intermediate superheater (12) for superheating steam between the turbine stages. The combustion chamber (2) is divided into a first and a second part (2a, 2b) by a wall (4) having one or more openings (42, 43) which takes up a minor part of the cross-section in the bed region and makes possible a limited exchange of bed material. The first part (2a) includes a nest of boiler tubes (11) for generating steam. The second combustion chamber part (2b) includes a nest of boiler tubes (12) for intermediate superheating of steam between the turbine stages. The combustion chamber parts (2a, 2b) are each connected to a fuel supply system (20, 21, 22 and 23, 24, 25, respectively).

Abstract: A method and a device for improving the efficiency of slag-bath reactions, for example in connection with sulfur removal from steel melts, involves stirring the melt with at least one inductive stirrer in such a way that the stirring force includes both a horizontal and a vertical component.

Abstract: The invention relates to a method for removing inclusions of foreign matter (for example slag inclusions) from a bath of molten metal. The method is characterized in that molten metal located in a bath in a vessel is rotated about a vertical axis by means of at least one electromagnetic stirrer, to cause the inclusions to move towards the center of the vessel where they agglomerate and float up to the bath surface. Molten metal substantially free from inclusions can then be tapped off from a lower part of the vessel, to one side of said axis.

Abstract: Apparatus for determining the location of surface defects on a test piece of electrically conductive material by scanning the surface with at least one sensor arrangement comprising proximity sensors based on eddy current induction. The test piece may be moveable, e.g. advanced, in relation to the holder arrangement which is arranged to move the sensor arrangement in a sweeping or scanning movement from one side of the test piece to the other. The position of the edge of the test piece, is determined successively, e.g. for each scan cycle and the location of detected cracks is calculated with a starting point from the detected edge position.

Abstract: A hollow arc furnace electrode comprises a central channel formed in its upper part as a tube and in its lower part as a passage extending through a graphite tip of the electrode. A metallic electrode portion is arranged around the central tube above the tip, which electrode portion is provided with channels for liquid coolant flow.

Abstract: In the event of an operational disturbance in a turbine-compressor unit of a PFBC plant, the turbine and the compressor are isolated from the bed vessel of the plant by closing a valve in the gas supply conduit to the turbine and by closing a valve in the conduit leading from the compressor. At the same time a valve is opened in a by-pass conduit between the compressor and the turbine. Combustion air is allowed to escape into the atmosphere via one or more blow-off valves. The bed vessel and/or a space between the pressure vessel and the bed vessel are supplied with inert gas in such a way that combustion in the bed is damped down.

Abstract: A device for sensing the free surface level of melt in a continuous casting mold having an electromagnetic stirrer consisting of stirrer coils and magnetic poles therefor disposed around the circumference of the mold. The device is characterized in that at least one elongated radiation source extending in the direction of casting is arranged on one side of the mold, and that a detector for the radiation with a small extension in the casting direction is arranged on substantially the diametrically opposite side of the mold but at a height different from that of the radiation source. In the radiation path from the source to the detector an oblong slot is provided for the passage of the radiation through the pole of a stirrer coil.

Abstract: A method and a device in connection with digital distance relays for obtaining a backup function in the event of faults in the digital signal processing and/or in the event of faults detected during automatic testing. The method comprises testing the distance relay continuously, in case of a faultless network, with respect to the digital signal processing by means of a central control unit. In case of a characteristic fault on the network, the distance relay is switched over from testing to protective function involving measurement by means of measurement signal units included in the distance relay. In case of a fault on the network and a simultaneous fault in the digital signal processing, fault signals from the measurement signal units, via time delay circuits and logical elements, bring about tripping of the line section subjected to the fault. When a fault is detected in the digital signal processing, an alarm function is triggered.

Abstract: Apparatus for heating intermediate ladles or tundishes, for example, in continuous casting processes. The apparatus comprises at least one coil having an iron core, which is disposed adjacent the ladle or tundish. The ladle or tundish and the coils are arranged so as to be movable with respect to each other. The ladle or tundish is adapted to be placed in a heating position adjacent to the coil, which is thus closely connected with the bottom or lower parts or corners of the ladle or tundish, in order primarily to heat the lowermost parts of the melt stored in the tundish.

Abstract: In horizontal continuous casting, the casting proceeds step-by-step with the forming strand being intermittently pulled from the mold. The strand forms with a skin with a melt inside of the skin and this melt is stirred by a magnetic stirrer on the outside of the mold. This forms a thin wall in the skin at that location, forming a breaking location or point where the skin pulls apart each time the strand is pulled forwardly. The mold is continuously fed with melt and the skin's strand reforms or welds together at the strand break.

Abstract: A method and a device for directional detection of a fault on a power transmission line extending between two stations (P, Q). In one of the stations (P) there is a travelling wave model which, by means of currents and voltages measured in the station, calculates the voltage distirbution along the line. The direction to a fault is determined by monitoring changes in calculated voltages in the two stations. If a fault occurs between the stations, the voltage change occurring in a station (Q) between the voltage existing prior to a fault and after a fault can be estimated as .vertline..DELTA.Uq.vertline., and the corresponding voltage change occurring in the other station (P) can be estimated as .vertline..DELTA.Up.vertline., whereby according to the invention the difference .vertline..DELTA.Uq.vertline.-.vertline..DELTA.Up.vertline.>0 signifies a fault on the line side of the station (P), i.e. a fault lying ahead of the measuring point. A fault lying behind station P is evidenced when .vertline..DELTA.Uq.

Abstract: A method and device for range limitation and direct tripping for protection in the event of a fault on an electrical power line extending between two stations (P, Q) involves employing a travelling wave model in one of the stations (P) which, with the aid of measured currents and voltages in that station, to calculate the voltage distribution at a number of control points along the line. The range of the protection device is indicated as the distance between the measuring station and that control point for which a voltage difference (.delta.u) becomes equal to zero. The voltage difference consists of the difference between the absolute value of a voltage differene between the absolute value of a voltage difference (.DELTA.u), formed as the sum of a voltage value (U") calculated with the travelling wave model for the control point at a certain time, and the corresponding voltage value (U') one half-period earlier and the absolute value of the latter voltage value.

Abstract: A press plant with a forming press of the pressure cell type for enhancing the forming space of the press, especially with regard to depth, which is accomplished according to the invention in that the tray has a planar bottom plate with a detachable tray frame resting thereon, the axial loads induced by the working pressure on the short ends of the tray frame in this manner being absorbed by an annular frame or the like, whereby the forming space of the inventive press plate will not be restricted by working pressure dependent dimensioning factors.

Abstract: An industrial robot having a gimbal-ring type suspension incorporating two axes renders therewith a translatorily movable arm swingable. According to the invention, the translatory movement is achieved in that the gimbal-ring type suspension, which can be swung with the aid of two motors, carries a part in the form of a box-like structure in which a platform provided with a rack can be slidably moved on guides, the platform being driven to translatory motion by a pinion. The platform carries a fourth, a fifth and a sixth motor, of which the fourth motor is able to rotate the arm about its longitudinal axis while the fifth and sixth motor drive their respective drive shafts for swinging the tool holder and rotating the same.