Abstract: A device for monitoring the unbalance of the electric power demanded on the conductive lines of an alternating current network of a three-phase internal installation. The device applies to all networks or three-phase installations which serve single-phase type devices in terms of variable number and power.

Abstract: A regulator system for a switching mode inverter generator feeding an inductively coupled load and seeing the load as a series resonant circuit having a resonant frequency which varies with its magnetic state comprises two switches which connect the load to the output of the inverter. Each switch comprises a switching element and switching terminals. A diode shunts the switching terminals of each switching element of each switch. A control loop slaves the output frequency of the inverter to the resonant frequency of the load. A second control loop is responsive to the inverter power output or the inverter supply voltage. The system is suitable for inductive heating furnaces as used in industry.

Abstract: A resistance heating device having a longitudinal axis and a substantially cylindrical graphite heating element with a connecting part for connection to an electric power source. The device has a sheath surrounding the graphite heating element, radially spaced therefrom and defining a gas tight chamber about the graphite heating element, the sheath being made from a refractory alloy sheet having angularly distributed longitudinal corrugations and an internal surface arranged to directly receive over its whole area radiation emitted by the graphite heating element when energized.

Abstract: The invention relates to a handling machine designed in such a way that it can move along a surface having a random slope.The machine has a central chamber and at least one adjacent peripheral chamber with an open side, which can be sealingly applied to the surface by means of gaskets. This application is obtained by producing a vacuum in at least one of the chambers. The displacement of the machine on the surface, e.g. with the aid of caterpillars, is improved by producing an overpressure in at least one other chamber.

Abstract: Antiseismic support structure for the pile block of a fast neutron nuclear reactor.It comprises a concrete covering slab resting on the reactor building structure. The vessel and components of the pile block are suspended on said slab in a well of said structure. The building rests on the ground by means of two superimposed floors, namely an upper floor and a lower floor. The two floors are separated from one another by elastic supports, permitting a horizontal oscillatory displacement with respect to one another with a view of filtering the horizontal components of the earthquake with respect to the vessel. These elastic supports are in particular fretted elastomer supports.

Abstract: Cold trap for purifying liquid sodium containing impurities of the type comprising, in a sealed enclosure cooled by a cooling fluid flowing in contact with its outer surface, in the upper part an economizer for lowering the temperature of the hot sodium and ensuring its introduction into the trap, and in the lower part the actual trap containing a filter plug, kept at its cold point temperature, wherein the enclosure is annular, the filter plug being located in the space between two concentric cylindrical ferrules.

Abstract: The process involves introducing into the structure (1) immersed in water, in the vicinity of the component (9) to be monitored, a means (30) of injecting water at a pressure higher than 40 MPa and in the form of a straight jet of a diameter less than 3.times.10.sup.-3 m. The injection means (30) is subsequently directed towards the component (9) to be monitored, and water is injected under pressure in such a way that the jet reaches the component (9). The position of the component after the action of the jet is monitored by a televisual means. When the pins of a guide tube (1) are to be monitored, the device also has, in addition to the televisual inspection means, a very long tube (30), in which an injection device having a nozzle in its lower part is arranged.

Abstract: The invention relates to a heat exchanger incorporating emergency cooling means, as well as to a fast neutron nuclear reactor incorporating such an exchanger.The emergency cooling means comprise an inlet pipe issuing into the secondary fluid inlet chamber and an outlet pipe issuing into the secondary fluid outlet chamber. The inlet pipe issues into a distributing ramp positioned below the lower tue plate and the outlet pipe issues into a collecting ramp positioned above the upper tube plate. The two ramps are positioned below the intake and discharge pipes for the secondary fluid.

Abstract: The device, for AC operation, is applicable more especially to the protection of very high tension installations. It comprises a rectifier (12), a comparator for comparing the rectified current and a threshold value (s) and for making, in the case of overshoot, a new comparison after a time equal to and 1/2T+.DELTA.T, T being the nominal period of the AC current and .DELTA.T a fraction of T of the order of a tenth, after overshoot. The new comparison is made with a circuit comprising a memory (22), a timer (24) and a circuit (34) including two inverters and an AND gate. Tripping is produced if overshoot occurs during the new comparison.

Abstract: Nuclear reactor cooled by a liquid metal comprising a main vessel sealed by a sealing slab, said vessel containing liquid metal overhung by a covering of inert gas, the reactor core being placed in a primary vessel integrated into the main vessel in such a way that the primary vessel at the outlet from the core constitutes a hot collector for the liquid metal and the space defined between the main vessel and the primary vessel constitutes a cold collector for the liquid metal, at least one heat exchanger supplied by the liquid metal contained in the hot collector under the action of at least primary pumps located in the main vessel, wherein the exchanger is positioned outside the main vessel at a level above that of the sealing slab and communicates with the hot collector by at least one intake pipe and with the cold collector by at least one outlet pipe, it being possible to empty the exchanger and pipes into the main vessel by gravity, the upper part of each exchanger being filled with the inert gas coverin

Abstract: An electric vapor boiler has a closed vessel (1) containing water, a steam or vapor outlet conduit (4), a conduit (6) supplying liquid and/or returning condensed vapor, and a electric resistance heating device (7) for each high or medium boiler voltage phase immersed in the water. Each heating device (7) includes a bare metallic resistance wire (8) immersed in the water and mounted in such a manner as to vibrate between a pair of vertical open-ended cylinders (13, 14) forming insulating screens. Each wire (8) is directly connected between a phase terminal (11) and ground, that is, the vessel (1) and has a plurality of parallel vertically spaced spires (18) offset symetrically with respect to each other on each side of a generatrix (16) of an oblique surface in the enclosure between the cylinders (13, 14) and extending obliquely to the vertical direction in the vessel (1). The outer cylinder (13) extends above the surface of the water.

Abstract: Apparatus for detecting the evolution of an acoustic signal, comprising an acoustic sensor, as well as circuits for the amplification, filtering, detection and measurement of the effective value of the signal supplied by the sensor. The apparatus comprises a smoothing circuit, a sawtooth generator, an adder, a circuit for adjusting the effective value by straight segments and a circuit for carrying out sequence tests. The apparatus is adapted for use in the monitoring of steam generators in fast neutron reactors.

Abstract: The present invention relates to a stack, particularly an atmospheric cooling tower. The stack comprises a shell with double curvature and a bearing structure or seating for the shell; the shell is dissociated from the seating and presents in its lower part a rigid peripheral ring via which it rests on this seating. The invention is more particularly applicable to the production of atmospheric cooling towers.

Abstract: The transmission of digital data takes place over a network comprising a data transmission line and a control and synchronizing line connecting together a master station, alone capable of transmitting over the control line, and several slave stations. The two lines are unidirectional and looped back to the master station and the stations transmit information in phase over the two lines. For that, each slave station comprises means for extracting clock information from the signal permanently present on the control line.

Abstract: The interface according to the invention is intended to receive temperature SRT and hygrometry SRH regulation signals from the temperature and hygrometry regulators. It sends heating SCC and ventilation SCV control signals to heating and ventilation devices of variable output. The interface has two positions, summer and winter. In summer, it regulates ventilation as a function of temperature (or possibly of hygrometry). In winter, it regulates the heating as a function of temperature; ventilation is then regulated by the application of a variable restriction on the extraction flow.