A tubular component for a pressurised-water nuclear reactor, has the following composition by weight: 0.8%≤Nb≤2.8%; traces≤Sn≤0.65%; 0.015%≤Fe≤0.40%; preferably 0.020%≤Fe≤0.35%; traces≤C≤100 ppm; 600 ppm≤O≤2300 ppm; preferably 900 ppm≤O≤1800 ppm; 5 ppm≤S≤100 ppm; preferably 8 ppm≤S≤35 ppm; traces≤Cr+V+Mo+Cu≤0.35%; traces≤Hf≤100 ppm; F≤1 ppm; the remainder being zirconium and impurities resulting from production. The tubular component has an outer surface with a roughness Ra less than or equal to 0.5 μm, obtained following a final mechanical polishing step. The outer surface has a roughness Rsk≤1 in absolute value and a roughness Rku≤10.

Apparatuses, systems, and methods of filtering debris from the bottom nozzle of a nuclear reactor while minimizing loss coefficients are disclosed herein, including a debris filter bottom nozzle with a plate-like body, a plurality of flow passages, and a filter positioned within at least one flow passage, wherein the at least one flow passage has a dimension based at least in part on a predetermined loss coefficient of the at least one flow passage and a predetermined filtration capability of the filter.

One embodiment provides a method of making an oxidation and corrosion resistant nuclear fuel. The method includes refining, by high energy ball milling (HEBM), a nuclear fuel powder comprising at least one nuclear fuel component and sintering the refined powder to form a nuclear fuel pellet. The method may further include adding a powdered dopant to the nuclear fuel powder. The refined powder includes the nuclear fuel powder and the powdered dopant.

A boiling water reactor includes a reactor building, a reactor cavity pool, a primary containment vessel, and a passive containment cooling system. The reactor building includes a top wall defining a penetration therein, a bottom wall, and at least one side wall, which define a chamber. At least a portion of the primary containment vessel is in the chamber. The passive containment cooling system includes a thermal exchange pipe including an outer pipe and an inner pipe. The outer pipe has a first outer pipe end and a second outer pipe end. The first outer pipe end is closed and in the primary containment vessel. The second outer pipe end is open and extends into the reactor cavity pool. The inner pipe has a first inner pipe end and a second inner pipe end, which are open. The second inner pipe end extends into the reactor cavity pool.

A boiling water reactor includes a reactor building, a reactor cavity pool, a primary containment vessel, and a passive containment cooling system. The reactor building includes a top wall defining a penetration therein, a bottom wall, and at least one side wall, which define a chamber. At least a portion of the primary containment vessel is in the chamber. The passive containment cooling system includes a thermal exchange pipe including an outer pipe and an inner pipe. The outer pipe has a first outer pipe end and a second outer pipe end. The first outer pipe end is closed and in the primary containment vessel. The second outer pipe end is open and extends into the reactor cavity pool. The inner pipe has a first inner pipe end and a second inner pipe end, which are open. The second inner pipe end extends into the reactor cavity pool.

This application relates to manufacturing of vacuum chambers of nuclear fusion reactors, and more particularly to a method, device and apparatus for machining grooves of poloidal segments of a vacuum chamber of a nuclear fusion reactor, and a computer-readable storage medium. The method includes: collecting three-dimensional (3D) point cloud data of surfaces of individual poloidal segments of the vacuum chamber; performing reverse model reconstruction, based on the three-dimensional point cloud data, to generate an actual 3D model to acquire a sectional view of the vacuum chamber; extracting a cross-reconstruction region between two adjacent poloidal segments; and calculating a target machining allowance of individual poloidal segments according to the cross-reconstruction region and a preset segment boundary to generate a machining strategy for the groove of individual poloidal segments.

This application relates to manufacturing of vacuum chambers of nuclear fusion reactors, and more particularly to a method, device and apparatus for machining grooves of poloidal segments of a vacuum chamber of a nuclear fusion reactor, and a computer-readable storage medium. The method includes: collecting three-dimensional (3D) point cloud data of surfaces of individual poloidal segments of the vacuum chamber; performing reverse model reconstruction, based on the three-dimensional point cloud data, to generate an actual 3D model to acquire a sectional view of the vacuum chamber; extracting a cross-reconstruction region between two adjacent poloidal segments; and calculating a target machining allowance of individual poloidal segments according to the cross-reconstruction region and a preset segment boundary to generate a machining strategy for the groove of individual poloidal segments.

A feedwater sparger repair assembly includes a cover plate having a partial cylindrical shape and having a nozzle opening and a pair of bolt openings extending through the cover plate. A nozzle is attached to the cover plate and surrounds the nozzle opening. A pair of T-bolts extend through a respective one of the pair of bolt openings and each include a shank having a threaded portion extending from an exterior side of the cover plate and a partial cylindrical head portion disposed at an end of the shank on an interior side of the cover plate. A pair of nuts are engaged with the threaded portion of the pair of T-bolts. The feedwater sparger repair assembly is adapted to be mounted to an opening that is cut into a core spray pipe in order to repair/replace a sparger that becomes cracked.

Method of fabricating structures, such as parts for use in nuclear power generation systems, are described herein. A representative method of fabricating a part for a nuclear reactor system includes additively manufacturing the part as a monolithic structure from a wire formed of an oxide dispersion strengthen (ODS) material, which includes an oxide material dispersed within a metal material. Specifically, the method can include directing a beam of thermal energy toward the wire to melt the wire, and permitting the melted wire to cool and solidify to form the part such that the oxide material remains substantially dispersed within the metal material. By maintaining the dispersion of the oxide material within the metal material, the ODS material can retain a good creep resistance, wear-resistance, corrosion resistance, and/or other ODS material property at elevated temperatures—even after fabrication.

A pressurized water reactor (PWR) includes a vertical cylindrical pressure vessel having a lower portion containing a nuclear reactor core and a vessel head defining an integral pressurizer. A reactor coolant pump (RCP) mounted on the vessel head includes an impeller inside the pressure vessel, a pump motor outside the pressure vessel, and a vertical drive shaft connecting the motor and impeller. The drive shaft does not pass through the integral pressurizer. The drive shaft passes through a vessel penetration of the pressure vessel that is at least large enough for the impeller to pass through.