Abstract:
A personal radiation protection garment that substantially contours to an operator's body is suspended from a suspension means. The garment is operable to protect the operator from radiation. The suspension means is operable to apply constant force. The suspension means allows operator wearing protective radiation garment to move freely in the X, Y, and Z spatial planes simultaneously, such that the protective radiation garment is substantially weightless to operator. A radiation protection face shield and flap can also be suspended from suspension means, such that face shield and flap are substantially weightless to operator. The suspension means can be mounted to a ceiling.
Abstract:
A method is for establishing a nuclear reactor core loading pattern (LP) for fuel assemblies and burnable absorbers (BAs). The method establishes an optimum LP through the steps of: a) providing nuclear data representing fuel assemblies and BAs in a nuclear reactor core; b) depleting the nuclear data to form a reference core depletion; c) incorporating the nuclear data into a system of linear equations of a nuclear design quality flux solution method; d) defining the system of linear equations to include constraints which accurately represent the neutron physics of the reactor; employing the equations as a constraint matrix for a MIP solver to find an optimum core pattern solution; f) repeating steps b) through e) updating the constraints and objective functions to satisfy specified engineering requirements and establish an optimum core loading pattern. An algorithm for deriving the system of equations is also disclosed.
Abstract:
In the method, a set of limits applicable to a test rod pattern design are defined, and a sequence strategy for positioning one or more subsets of the test rod pattern design is established. Reactor operation on a subset of the test rod pattern design, which may be a subset of fuel bundles in a reactor core for example, is simulated to produce a plurality of simulated results. The simulated results are compared against the limits, and data from the comparison is provided to indicate whether any of the limits were violated by the test rod pattern design during the simulation. A designer or engineer may use the data to determine which operator parameters need to be adjusted (e.g., control blade notch positions for example) in order to create a derivative rod pattern design for simulation, and eventually perfect a rod pattern design for a particular core.
Abstract:
A resistance member (e.g., fuel holding portion of the lower tie plate) is provided at the lower end of the fuel assembly. Provision is made of a coolant ascending path in which said water rods have coolant inlet ports that are open in a region lower than the resistance member to upwardly guide the coolant, and a coolant descending path which has a coolant delivery port that is open in a region higher than the resistance member to downwardly guide the coolant. The coolant ascending path and the coolant descending path are communicated with each other at their upper end portions.
Abstract:
The invention relates to a method and device for production of non-contaminated rods from MOX tablets in columns, within a confinement chamber divided into compartments, by means of a centering and aligning element for the tablets and a long pushrod with a sensitive drive.
Abstract:
The tie rod repair apparatus includes a tie rod secured at its upper end to the shroud flange at the top of the shroud. The lower end of the tie rod passes through an opening in the shroud support plate without imposing a load on the plate. The lower end of the tie rod is anchored to the lower end of the core shroud support cylinder such that the compressive load path exerted by the tie rod to restrain the cracked shroud passes directly through the shroud support cylinder and the assembly of shroud cylinders bypassing the shroud support plate.
Abstract:
A nuclear power plant and an operation method of the nuclear power plant, which can uprate plant power without greatly modifying the construction of plant equipment, while keeping a core's pressure loss characteristic, a safety margin, and a design margin in the transient state substantially the same as those before the power uprate. Thermal power in a second operation cycle of a nuclear reactor is uprated from thermal power in a first operation cycle preceding the second operation cycle at least one operation cycle. A proportion of steam extracted from a steam system and introduced to a feedwater heater, which is in particular extracted from an intermediate point and an outlet of a high pressure turbine, with respect to a flow rate of main steam is reduced in the second operation cycle from that in the first operation cycle such that temperature of feedwater discharged from the feedwater heater lowers in the range of 1° C. to 40° C. in the second operation cycle.
Abstract:
A reactivity control rod adapted to be used in a reactor core of a fast reactor and disposed at a substantially central portion of the reactor core for controlling a reactivity therein. The reactivity control rod includes a wrapper tube surrounded by a plurality of fuel rods in a reactor core, and a plurality of neutron absorber rods arranged in the wrapper tube. At least one of the plurality of neutron absorber rods includes a cladding tube and a mixture filled in the cladding tube. The mixture is composed of a neutron absorber that absorbs a neutron and a neutron moderator that moderates the neutron.
Abstract:
Disclosed is a fire-resistant lead-free shield material having high shielding ability against nuclear or electromagnetic radiation, and excellent bending workability and handling performance. The shield material comprises a composite material consisting of an organic material and a metal or metal compound having a nuclear or electromagnetic radiation-shielding ability. The composite material is formed into a given shape, such as a plate shape, and wrapped with a cloth-like sheet formed of glass fibers, metal fibers or carbon fibers. Alternatively, the shield material comprises a shielding element consisting of an elastic polymeric organic compound and a particle having a nuclear or electromagnetic radiation-shielding ability, such a heavy metal or ferrite. The shield material also includes either one of a film made of polyethylene, nylon, polyester or metal, a wire mesh formed of nylon fiber or metal fiber, and a plate- or rod-shaped member having a surface formed with a protrusion, which is compression-bonded onto or in the vicinity of a surface of the shielding element, or inside the shielding element.
Abstract:
A method for mitigating stress corrosion cracking of a component exposed to a high temperature water in a high temperature water system is provided. The method comprises the steps of lowering corrosion potential conditions to a desired low corrosion potential in the high temperature water environment; and introducing a first material comprising zinc into the high temperature water environment, such that the desired low corrosion potential facilitates transport of the first material into cracks in a structure communicative with the high temperature water environment.