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 medical valve transitions between an open mode that permits fluid flow, and a closed mode that prevents fluid flow. To that end, the medical valve has a housing with an inlet and an outlet, a rigid member movably mounted within the housing, and a resilient member with a sealing portion. The housing also has at least one relief zone that is in fluid communication with the outlet when the valve is in the closed mode. The rigid member may have a proximal end, a distal end, and a flow channel. The relief zone may be radially outward from the sealing portion. The sealing portion may seal the valve and prevent fluid from passing through the valve when in the closed mode.

Abstract: A photonic spectrometry device is provided. The photonic spectrometry device includes at least one sensor capable of detecting photons, at least one photon-emitting calibrating source having a reference spectral line, and processing means capable of providing, for the or each sensor, a measurement spectrum corresponding to the measurements, made by the or each sensor, of the radiation from a product during a time interval, and establishing, on the basis of the or each measurement spectrum, a net corrected spectrum according to a measured characteristic line corresponding to the or each calibrating source. The or each calibrating source is positioned outside the or each sensor.

Abstract: A photonic spectrometry device is provided. The photonic spectrometry device comprises several identical spectrometers each spectrometer comprising a radiation sensor and being capable of providing a measurement spectrum corresponding to the measurements of the sensor during a time interval, the spectrometers being capable of performing measurements simultaneously on one same radiation-emitting product and of providing measurement spectra for one same time interval, and a processor capable of determining a net spectrum from each of the measurement spectra provided by the spectrometers for one same time interval, and of determining a global spectrum resulting from the summation of the net spectra determined for one same time interval.

Abstract: A method for determining tube support plate blockage of a steam generator includes the following steps: measuring at least five different eddy current values per tube support intersection; calculating a nominal clean fit radius of flow hole; determining a center signal response; converting the center signal response to a deposit thickness; determine an edge reduction; converting the edge reduction to an edge thickness; calculating the resulting flow hole radius; verifying the reasonableness of the resulting flow hole radius; and determining a virtual calibration range.

Abstract: The invention relates to a method of decontaminating an oxide layer-comprising surface of a component or a system of a nuclear facility, wherein the oxide layer is treated with gaseous nitrogen oxide (NOx) as oxidizing agent.

Abstract: A gland member within a medical valve is configured to have a substantially consistent or enlarging internal volume as the valve transitions from a closed mode to an open mode. The valve has a housing forming an interior containing a flow path, and a stationary post member within the interior. The post member has a lumen that is a part of the flow path. The lumen has an opening to the interior of the housing. The valve further includes a gland member circumscribing the post member to produce a variable volume region formed at least in part between the gland member itself and the post member. The variable volume region is a part of the flow path, while the gland member occludes the post lumen opening when in the closed mode. The variable volume region has an open volume that is no less than its closed volume.

Abstract: A device for turning a container about a turning axis is provided. The device includes a stationary holding member and two bearing members which are spaced apart along the turning axis on each side of a space for receiving a container, and which are capable of being used for bearing on the container while enabling the rotation of the container about the turning axis relative to the bearing members. The device includes a movable holding member that is mounted onto the stationary holding member so as to rotate about the turning axis, at least one bearing member being supported by the movable holding member while being mounted onto the movable holding member so as to rotate about the drive axis, the or each bearing member supported by the movable holding member not rotating about the turning axis relative to the stationary holding member when the movable holding member rotates about the turning axis relative to the stationary holding member.

Abstract: A method for removing corrosion products from a system, the method including: adjusting the system temperature to between 115° F. to 212° F.; injecting a cleaning dissolution solvent into the system; injecting a gas into the system after the system is filled with the cleaning dissolution solvent; the gas mixing with the solvent in the system; draining the solvent from the system after a predetermined period of time of dissolution; injecting a passivation composition into the system; injecting a gas into the system, the gas mixing the passivation composition; draining the system of the composition after a predetermined period of time of passivation; rinsing the system with a low volume solution; and rinsing the system at with a full volume solution.

Abstract: A method for selecting a loading map for a nuclear reactor core including the following steps: a) providing production data relating to the nuclear fuel assemblies, b) providing neutron data which are representative of the operation of the core, c) calculating the three-dimensional distribution of the local power in the core, d) calculating the extreme value reached by at least one thermomechanical parameter within the nuclear fuel assemblies, and e) selecting, in accordance with the extreme values calculated, a loading map from the loading maps envisaged. A system, computer program and storage medium for selecting a loading map for a nuclear reactor.

Abstract: A method including placing around the shoulder of the lid a ring-shaped gasket formed by a metal strip maintained on the vertical wall of the shoulder by self-maintaining members firmly attached to the strip, placing the lid bearing the ring-shaped gasket above the vessel by positioning it at a determined height, carrying out a cleanliness inspection of the gasket plane, lowering and laying the lid on the vessel so that the end side edges of the strip will come into contact with a horizontal wall of the lid and of the vessel flange respectively and attaching this lid on the vessel.

Abstract: A fixed cluster for the core of pressurized-water nuclear reactor including rods and a holder for rods. The holder includes: an upper head; fins extending radially towards the outside from the upper head; systems for mounting the rods and distributed on the fins; and at least two abutment elements on the upper plate of the core, each of the abutment elements protruding longitudinally from a respective fin beyond the mounting systems so as to be vertically oriented towards the top when the fixed cluster is provided on a nuclear fuel assembly.

Abstract: A process of cleaning resin out of an electrical generator parallel ring is provided. The process includes 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 leak detecting apparatus for detecting flaws in a surface submerged in liquid is provided that includes a vacuum head for contacting the surface and forming a vacuum chamber filled with liquid between the surface and the vacuum head, the vacuum head including a multi-surface elastomer seal for contacting the surface; and a vacuum generator for pulling gas through a flaw in the surface into the vacuum head and to the gas separation chamber so as to displace the liquid from the gas separation chamber. A method for detecting flaws in a surface submerged in liquid is also provided.

Abstract: The present invention provides a method of operating a Boiling Water Reactor, having the steps of analyzing LPRM signals for oscilliatory behavior indicative of neutron-flux-coupled density wave oscillations, determining if oscilliatory behavior is present in the signals; initiating a reactor protective corrective action if the oscilliatory behavior is determined, and in addition, initiating corrective actions if neutron uncoupled oscillations are possible. Detecting the later is performed through analytically determined exclusion zone on the power flow map or by on-line stability calculations for several high power channels.

Abstract: A method for design of a fuel assembly for nuclear reactors, including structural components made from zirconium alloy: the mean uniaxial tensile or compressive stress to which the components are subjected during the assembly life is calculated, the zirconium alloy of which the components are made is selected according to the following criteria: those components subjected to an axial or transverse compressive stress of between ?10 et ?20 MPa are made from an alloy with a content of Sn between Sn=(=0.025??0.25)% and Sn=?0.05?%: those components subjected to such a stress of between 0 et ?10 MPa are made from an alloy the Sn content of which is between Sn=traces and Sn=(0.05?+1)%: those components subjected to such a stress of between 0 and +10 MPa are made from an alloy the Sn content of which is between Sn=0.05% and Sn=(0.07?+1)%: and those components subjected to such a stress of between +10 and +20 MPa are made from an alloy the content of SN of which is between 0.05% and 1.70%.

Abstract: A process of collecting and manipulating data to measure the gap between structural components of a piece of equipment or a system is disclosed and claimed. The technique uses ultrasonic zero degree longitudinal waveforms to measure the gap. The technique subtracts the average of two adjacent waveforms from the waveform being processed to remove data from reflections from the components to reveal the reflections generated by the gap.

Abstract: A medical valve transitions between an open mode that permits fluid flow, and a closed mode that prevents fluid flow. To that end, the medical valve has a housing with an inlet and an outlet, a rigid member movably mounted within the housing, and a resilient member with a sealing portion. The housing also has at least one relief zone that is in fluid communication with the outlet when the valve is in the closed mode. The rigid member may have a proximal end, a distal end, and a flow channel. The relief zone may be radially outward from the sealing portion. The sealing portion may seal the valve and prevent fluid from passing through the valve when in the closed mode.

Abstract: A position measuring system detects an extreme position of a guide rod which extends along a path that is rectilinear relative to a guide system and can be moved along the rectilinear path, wherein the system operates reliably, and requires a minimum of electrical lines. The position measuring system is equipped with a plurality of sensor elements and a magnetic element, wherein the magnetic element is configured to form a magnetic field. The magnetic element is connected to the guide rod. Each sensor element is configured to detect a magnetic field within a detection region, a field strength of the magnetic field being greater at the location of the sensor element than a predefined threshold value. At least one sensor element is connected to the guide system and is arranged in an environment of the path. A corresponding measuring method uses the position measuring system to detect the extreme positions.