Abstract: A jet pump stabilizer is disclosed and claimed. The stabilizer includes a clamp body that is affixed about the riser pipe. Two U-clamps are connected to the clamp body, each U-clamp positioned about a jet pump mixer section. A wedge assembly is positioned between the clamp body and each mixer pipe, cooperating with the clamp body and U-clamps to laterally restrain the mixer sections. A clamp ring is positioned about each mixer section and retained in place by the U-clamps, wedge assemblies, and clamp body. A sealing ring is moveably connected to the clamp ring such that it is biased toward engagement with the jet pump diffuser. Seals provided on the stabilizer engage the jet pump assembly above and below the slip joint, preventing vibration-inducing leakage through the slip joint.

Abstract: A nuclear reactor is provided that includes a core with nuclear fuel assemblies; a circuit for cooling the core in which circulates a fluid coolant; and a device provided for injecting nanoparticles into the fluid coolant. The nanoparticles include first nanoparticles of a first type having a first form factor of less than two, and second nanoparticles of a second type different from the first type having a second form factor greater than two, the nanoparticles comprising between 10% and 90% by weight of the first nanoparticles and between 90% and 10% by weight of the second nanoparticles.

Abstract: The strip is of the type comprising a wall portion for delimiting a cell for receiving a fuel rod and allowing flow of a coolant upwardly through the spacer grid, a spring provided on the wall portion for biasing a fuel rod extending through the cell away from the wall portion, the spring being cut out in the strip and delimited by a slot and a motion limiter formed in the strip on the wall portion to limit motion of a fuel rod received in the cell towards the wall portion against action of the spring. According to one aspect of the invention, the motion limiter is located on an edge of the slot opposite the spring and defines a risen portion on the edge.

Abstract: A nuclear plant has a containment shell and a pressure relief pipe connected thereto in which a blowing device and a Venturi washer placed in a container with a washing liquid are connected in series. Even the finest particles or aerosols carried by air are held in the Venturi washer with a very high degree of reliability and the release thereof in environment is excluded in a particularly reliable manner in the case of decompression even associated with seal failures. For this purpose, the size of the blowing device and the Venturi washer are selected in such a way that during the operation of the blowing device a flow rate of liquid in the Venturi washer flowing to the decompressing pipe is higher than 130 m/sec, preferably higher than 180 m/sec.

Abstract: A resin removal tooling system for electric generator parallel rings including: a non-rotating sheath; a shaft mounted in the non-rotating sheath; a cleaning ball attached to the shaft, the non-rotating sheath positioning the cleaning ball; a high speed motor coupled to the shaft for rotating the shaft; a variable power supply connected to the high speed motor; and a tachometer for measuring a rotational speed of the high speed motor and the cleaning ball. A process of cleaning resin out of an electrical generator parallel ring including the following steps: inserting a cleaning ball mounted on a shaft into the parallel ring; verifying a location of the cleaning ball; rotating the shaft; measuring a rotational speed of the cleaning ball with a tachometer; and removing resin with the cleaning ball.

Abstract: A nuclear fuel assembly for boiling water reactor is provided. The nuclear fuel assembly includes a base, a head, a bundle of fuel rods extending longitudinally between the base and the head, a tubular fuel channel encasing the bundle of fuel rods, and at least one fuel channel spacer for transversely spacing the fuel assembly from an adjacent element. The or each fuel channel spacer includes a support having at least one plate and at least one corresponding leaf spring supported by the corresponding plate, the or each plate being fixed to a corresponding sidewall of the fuel channel.

Abstract: A lower nozzle for use in a nuclear fuel assembly provided. The lower nozzle is of the type having an axis and comprising a transverse lower tie plate for channelling the coolant through the lower tie plate and a tubular skirt extending axially from the periphery of the lower tie plate, the skirt delimiting an axial housing closed at one end by the lower tie plate and open at the opposite end, a debris filter configured for axial insertion in the housing and snap-fit springs for retaining the debris filter in the housing after insertion. The springs are configured to shift the debris filter axially towards the lower tie plate.

Abstract: An apparatus for detecting a magnetically conductive object in a detection area has an electrical coil and at least one sensor element. The apparatus is intended to be as free of degradation processes as possible and thus requires little maintenance and is configured and set up with the highest possible degree of redundancy and measurement reliability. For this purpose, the coil is set up to form a magnetic field in the detection area and the sensor element is configured to detect a magnetic field with a field strength, the magnitude of which is greater than a predefined threshold value. The threshold value is set to be higher than the field strength present in the detection area when the magnetically conductive object is absent and lower than the field strength present therein when the object is present.

Abstract: For implementing startup and priming phases of a vegetable carbon production method, an installation includes a generator of hot gases with low oxygen content, and a fan downstream which boosts the hot gases into a lower part of a reactor. The reactor includes a column of substantial height whose upper inlet, with a temperature T3 of less than 65° C., is used to continuously load and add biomass and whose lower part has a grid for support and removal of the load, an underlying injection chamber for the gases from the generator, and a mechanism for retrieving processed substances. The installation also includes, at the outlet for cold gases at temperature T3 at the top of the reactor column, a thermal post-combustion chamber for the extracted gases, a heat exchanger, a fan, a second heat exchanger, a vent and connecting pipes.

Abstract: The inventive viscous damping tube stabilizer includes modules or capsules containing a viscous material. Adjacent capsules are linked end to end by a flexible cable, allowing the device o pass through curves such as the U-bend regions of steam generator tubes. The weight of the entire assembly will keep it essentially connected to the tube inner diameter such that any tube vibration is transmitted to the stabilizer. The viscous material may only partially fill the capsules such that even under small motion the material can slip and slide past each other, and/or bump into walls, each microscopically absorbing some of the tube energy. By creating multiple cells inside the capsule, the capsule then have good operating characteristics no matter to what angle the individual capsule is oriented as it rests on the full U-bend. The viscous material may completely fill the capsules, which also have a perforated member positioned therein.

Abstract: A process of incorporating technetium into an electroless deposit, forming an alloy that is extremely resistant to corrosion and reduces the mobility of technetium on a geologic time scale is disclosed and claimed. The process includes providing a liquid containing technetium, such as an aqueous waste stream generated during the used nuclear fuel reprocessing activities. The technetium is collected and concentrated, and provided into an electroless deposition bath. A substrate, such as suitably prepared zero valent iron or stainless steel, is introduced into the bath to initiate autocatalytic electroless deposition of the technetium onto the substrate due to the difference in electrochemical potential between the plating bath and ti metals in solution. This causes a layer of technetium metal to form on the substrate.

Abstract: A debris filter for a nuclear reactor installation is provided. The debris filter comprises a plurality of plates arranged side-by-side in a spaced relationship and delimiting between them flow passages extending through the debris filter from a lower inlet face to an upper outlet face of the debris filter, each passage having an intermediate section offset with respect to an inlet section and an outlet section. At least one of the plates is formed with debris catching features distributed along the plate and protruding into at least one passage delimited by the plate.

Abstract: The strip is of the type comprising a wall portion for delimiting a cell with interlaced strips, a spring formed in the strip and provided on the wall portion for biasing a fuel rod extending through the cell away from the wall portion, the spring comprising a cantilevered tab formed in the strip and a contact portion formed at least partially in the tab and protruding from the tab for contacting a fuel rod received in the cell.

Abstract: The invention relates to a nuclear reactor primary circuit comprising a primary pipeline (30), which defines an internal volume (32) and in which a primary nuclear reactor coolant downwardly runs, an additional pipeline (26) which is branched to the primary pipeline (30) and defines an internal volume communicating with the internal volume (32) of the primary pipeline (30) and a cuff (36) whose first end (50) is connected to the additional pipeline (26) and the second free end (52) is positioned in the internal volume (32) of the primary pipeline (30). According to said invention, the second end (52) is delimited by a free peripherial edge (53) comprising at least one upstream and downstream sections (56, 58) which are oriented towards the upstream, wherein the upstream section (56) penetrates into the internal volume (32) deeper from the primary pipeline (30) than the downstream section (58).

Abstract: A method for working on a defective heating element of a pressuriser comprising a tank lying flat along a longitudinal axis and elongate heating elements extending within the tank, and at least one spacer plate through which the heating elements pass and which is capable of maintaining a transverse spacing between the heating elements is provided. The method includes cutting at least one spacer plate around the heating element so as to detach said heating element from said spacer plate, and then extracting the heating element from the tank in one single piece.

Abstract: The invention relates to a method for regulation of operational parameters of the core of a pressurised water nuclear reactor comprising: a step of acquisition of values (FH, FB, TBC, TBF, Q) which are representative of the conditions of operating of the core of the reactor; a step of evaluation of the actual values (Tmoye, AOe, {circumflex over (P)} maxe) of the operational parameters at least according to the values acquired (FH, FB, TBC, TBF, Q); a step of selection of a control law for the concentration of a neutron-absorbent component ([B]) and for the positions of insertion (Z1 to Z5) of the groups (P1 to P5) of rods selected from at least the first and second control laws which are different from one another; and a step of regulation of the operational parameters by means of the control law selected, according to set points (Tmoyc, AOc, {circumflex over (P)} maxc) relative to the said parameters and to the actual values (Tmoye, AOe, {circumflex over (P)} maxe) evaluated.

Abstract: An assembly of the type having a water channel extending along a longitudinal axis and having an upper section of larger cross-section area than a lower section and at least one fuel rod receiving groove extending longitudinally on the outer surface of the lower section, fuel rods extending longitudinally and disposed around the water channel and fixing members for fixing at least one fuel rod to the water channel in the at least one groove below the upper section. According to one aspect of the invention, the at least one groove extends along the upper section such that a fuel rod received in fixing members is longitudinally extractable or insertable from the upper end side of the fuel assembly.

Abstract: A spacer grid for a nuclear fuel assembly for a light water reactor delimits a substantially regular array of cells housing nuclear fuel rods. The spacer grid further including supporting members which project into the cells from the peripheral belt of walls. The inner surface of at least one supporting member has before irradiation a concave shape in a plane transverse to the longitudinal direction. The inner surface of the contact part of the supporting member also has a convex shape in a longitudinal plane orientated radially with respect to the central axis of the corresponding cell before irradiation.

Abstract: A spring mounting device in a cladding tube for nuclear fuel, comprising a spring distributor, a spring loader in the cladding tube, the distributor supplying the springs to the loader, said loader comprising a longitudinal slide to receive the spring, a pusher in order to set the spring into place in the cladding tube and is able to move in the slide, means of displacement of said pusher, said device comprising mechanical means in order to associate the actuation of the means of displacement with that of the spring distributor.

Abstract: A hatch cover is provided for a hatch of a nacelle for a wind driven power plant. The hatch cover includes several segments configured to remain within a hatch opening when a hatch is in an open position.