Patent application number | Description | Published |
20090052607 | Spacer Grid for Close-Spaced Nuclear Fuel Rods - A spacer grid can be applied to close-spaced nuclear fuel rods. The spacer grid is directed to solve the problem in which, as the outer diameter of each nuclear fuel rod increases due to the use of dual-cooled nuclear fuel rods for improving cooling performance and obtaining high combustion and high output power, the gap between the neighboring nuclear fuel rods is narrowed to thus make it impossible to use an existing spacer grid. The spacer grid is a combination of unit grid straps, each of which has supports for supporting each of the nuclear fuel rods set in a narrow array and has a sheet shape, which are combined with each other. The supports are located at positions shifted from the longitudinal central line of each unit grid strap toward sub-channels. | 02-26-2009 |
20090060117 | Guide thimble of dual tube type structure nuclear fuel assembly - Disclosed herein is a guide thimble of a nuclear fuel assembly, which is capable of improving the cooling performance and the stability of a nuclear fuel, preventing a flow split in dual-cooling nuclear fuel rod and guide thimble sub channels for obtaining high combustion degree and high power, and minimizing a neutron absorption section in a reaction degree region. Since the guide thimble having the dual tube type structure is adopted, a flow split in the fuel rod and guide thimble sub channels can be reduced, and the degradation in performance of nuclear fuel due to increase of a neutron absorption section can be prevented. In order for compatibility with an existing control rod, a typical guide tube is used as an inner guide thimble, and an outer guide thimble is provided outside the inner guide thimble. Thus, the guide thimble has the dual tube type structure as a whole, and is coupled to the upper and lower end fittings so that it can prevent a flow unbalance due to the flow split in the fuel rod and guide thimble sub channels. | 03-05-2009 |
20100027734 | SPACER GRID FOR DUAL-COOLING NUCLEAR FUEL RODS USING INTERSECTIONAL SUPPORT STRUCTURES - A spacer grid for dual-cooling nuclear fuel rods arranged at a narrow interval. The spacer grid solves the problem in which, since the dual-cooling nuclear fuel rods are used to improve the cooling performance and stability of nuclear fuel and obtain high burnup and output, the outer diameter of each dual-cooling nuclear fuel rod is increased, and thus the gap between each dual-cooling nuclear fuel rod and the grid strap is decreased. The spacer grid includes first grid straps and second grid straps, which are crossed and arranged in transverse and longitudinal directions at regular intervals and have the shape of a flat strip, and support structures, which are fitted into the first and second grid straps around intersections of the first and second grid straps so as to support the dual-cooling nuclear fuel rods. | 02-04-2010 |
20100128835 | INTERMEDIATE END PLUG ASSEMBLY FOR SEGMENTED FUEL ROD AND SEGMENTED FUEL ROD HAVING THE SAME - An intermediate end plug assembly for a segmented fuel rod can stably support the fuel rod to the end of its cycle even if an interval between the fuel rods becomes narrow due to application of a dual-cooled fuel rod, and reduce excess vibration induced by flows of interior and exterior channels of the dual-cooled fuel rod for obtaining high burnup and output. To this end, the fuel rod has a segmented structure so as to make its length short. A lower intermediate end plug includes at least one channel hole, through which a coolant flows into an internal channel of the fuel rod, so that a possibility of causing departure from nuclear boiling ratio (DNBR) of the dual-cooled fuel rod is reduced. | 05-27-2010 |
20100142668 | POROUS PLENUM SPACER FOR DUAL-COOLED FUEL ROD - A porous plenum spacer is inserted into the plenum of a dual-cooled fuel rod having concentric inner and outer cladding tubes. The porous plenum spacer includes a hollow cylindrical body inserted into the annular space between the inner and outer cladding tubes. The hollow cylindrical body includes a plurality of through-holes formed in an outer circumference thereof or at least one groove formed in one of outer and inner circumferences thereof in a lengthwise direction. Pores formed by the through-holes or the grooves of the hollow cylindrical body of the porous plenum spacer are allowed to secure a space containing fission gas inevitably generated by a nuclear reaction. | 06-10-2010 |
20100172460 | PERFORATED PLATE SUPPORT FOR DUAL-COOLED SEGMENTED FUEL ROD - A perforated plate support supports dual-cooled fuel rods, each of which has concentric outer and inner tubes and is coupled with upper and lower end plugs at upper and lower ends thereof, and guide thimbles, each of which is used as a passage for a control rod. The perforated plate support is formed as a support plate having the shape of a flat plate, which includes internal channel holes, each of which has a diameter corresponding to an outer diameter of the inner tube, guide thimble holes, each of which has a diameter corresponding to an outer diameter of the guide thimble, and sub-channel holes around each internal channel hole. The upper or lower end of the dual-cooled fuel rod is coupled to the support plate such that the outer diameter of the inner tube is matched with the diameter of the internal channel hole. | 07-08-2010 |
20100266094 | DUAL-COOLED NUCLEAR FUEL ROD HAVING ANNULAR PLUGS AND METHOD OF MANUFACTURING THE SAME - A dual-cooled nuclear fuel rod and a method of manufacturing the same are provided. The nuclear fuel rod includes an outer cladding tube having a circular cross section, an inner cladding tube having an outer diameter smaller than an inner diameter of the outer cladding tube, and a length longer than the outer cladding tube, and located in parallel in the outer cladding tube, a pellet charged in a space between the outer and inner cladding tubes and generating energy by nuclear fission, and first and second end plugs coupling opposite ends of the outer cladding tube to stepped outer joints formed on outer circumferences of first ends thereof and coupling opposite ends of the inner cladding tube to stepped inner joints formed on inner circumferences of the first ends thereof. | 10-21-2010 |
20110051882 | TRUSS-REINFORCED SPACER GRID AND METHOD OF MANUFACTURING THE SAME - A truss-reinforced spacer grid and a method of manufacturing the same are provided, in which truss members having a small diameter are woven to form a truss structure surrounded by an external plate, and the truss structure is joined to the external plate to thereby improve the strength of the mechanical structure. The truss-reinforced spacer grid includes a truss structure in which horizontal trusses formed by horizontally weaving a plurality of truss members are vertically disposed at regular intervals, and an external plate is joined with ends of the horizontal trusses and surrounds the truss structure. | 03-03-2011 |
20110064184 | UNIT SPACER GRID STRAP, UNIT SPACER GRID, AND SPACER GRID FOR NUCLEAR FUEL RODS - A spacer grid for nuclear fuel rods includes a plurality of unit spacer grids stacked one on top of another. Each unit spacer grid includes a plurality of unit spacer grid straps disposed at regular intervals in a row, and a plurality of fixing grid straps connected to respective opposite ends of the unit spacer grid straps so as to fix the unit spacer grid straps. Each unit spacer grid strap has convexities alternating with each other on opposite sides thereof at regular intervals, and at least one of the convexities has a diameter greater than the others. The unit spacer grids are rotated in one direction by a 90 or 180 degree angle when being stacked. | 03-17-2011 |
20120283161 | LUBRICATING OIL COMPOSITION - Disclosed is a lubricating oil composition which includes a diester-based base oil having an asymmetric structure in which the number of carbons of the alkyl chain bound to one ester group with respect to a central atom is two more than that of the alkyl group bound to the other ester group, and which has low viscosity and a comparatively small amount of evaporation at high temperature. When this composition is used for a motor of a small hard disk, power consumption can be reduced and stability at high temperature can be enhanced. | 11-08-2012 |
20130051714 | HYDRODYNAMIC BEARING ASSEMBLY AND METHOD OF MANUFACTURING THE SAME - There are provided a hydrodynamic bearing assembly and a method of manufacturing the same. The hydrodynamic bearing assembly includes: a lubricating oil filled so as to form a liquid-vapor interface between stationary members and rotating members; and a lipophilic coating formed on the liquid-vapor interface of the lubricating oil so as to prevent lubricating oil leakage. Therefore, the lipophilic coating is formed on the interface of the lubricating oil and an oil repellent material is formed on a surface of at least one of the stationary members and the rotating members, whereby the scattering and the leakage of the lubricating oil may be effectively prevented. | 02-28-2013 |
20130082547 | SEALING RESIN COMPOSITION FOR HDD MOTOR AND HDD MOTOR FABRICATED BY USING THE SAME - There are provided a sealing resin composition for a hard disk drive (HDD) motor and a HDD motor fabricated by using the same. The sealing resin composition includes 40 to 80 parts by weight of epichlorohydrin-4,4-isopropylidene diphenol resin; 5 to 20 parts by weight of acrylated ester; and 5 to 15 parts by weight of acrylated epoxy. The sealing resin composition containing a UV curable epoxy resin is used as a sealing material of the adhering part of the FPC of the HDD motor, whereby generation of outgas in the adhering part may be reduced. | 04-04-2013 |
20130082577 | ADHESIVE RESIN COMPOSITION FOR HDD MOTOR AND HDD MOTOR FABRICATED BY USING THE SAME - There are provided an adhesive resin composition for a hard disk drive (HDD) motor and a HDD motor fabricated by the using the same. The adhesive resin composition includes: 45 to 55 parts by weight of an urethane methacrylate oligomer, 35 to 45 parts by weight of hydroxylalkyl methacrylate, 1 to 3 parts by weight of an acrylic acid, 1 to 2 parts by weight of organic hydroperoxide, and 2 to 5 parts by weight of a photo initiator. The HDD motor may be fabricated using the adhesive resin composition for a HDD motor prepared by controlling contents of an UV curable adhesive and a primer to reduce generation of outgas, whereby improved reliable quality of the motor may be obtained. | 04-04-2013 |
20130085090 | LUBRICATING OIL COMPOSITION FOR FLUID DYNAMIC BEARING AND HDD MOTOR FABRICATED BY USING THE SAME - There are provided a lubricating oil composition for a fluid dynamic bearing and a hard disk drive (HDD) motor fabricated by using the same. The lubricating oil composition for a fluid dynamic bearing, includes: aliphatic mono carboxylic acid ester having a total of carbon numbers of 26 to 40, as a base oil, obtained by esterification between alcohol represented by the following Chemical Formula 1; and a straight or branched saturated aliphatic mono carboxylic acid having carbon numbers of 2 to 16: | 04-04-2013 |
20130090275 | LUBRICATING OIL COMPOSITION FOR FLUID DYNAMIC BEARINGS AND HDD MOTOR FABRICATED USING THE SAME - There are provided a lubricating oil composition for a fluid dynamic bearing and and a hard disk drive (HDD) motor fabricated by using the same. The lubricating oil composition for a fluid dynamic bearing includes: an aliphatic mono carboxylic acid ester, as a base oil, obtained by esterification between carboxylic acid represented by the following Chemical Formula 1; and isopropyl alcohol: | 04-11-2013 |
20130090276 | LUBRICATING OIL COMPOSITION FOR FLUID DYNAMIC BEARING AND HDD MOTOR FABRICATED USING THE SAME - There are provided a lubricating oil composition for a fluid dynamic bearing and a hard disk drive (HDD) motor fabricated using the same. The lubricating oil composition for a fluid dynamic bearing includes: an aliphatic mono carboxylic acid ester, as a base oil, obtained by esterification between alcohol represented by the following Chemical Formula 1; and 2-ethylbutanoic acid: | 04-11-2013 |
20130162074 | SEALING RESIN COMPOSITION FOR HDD MOTOR AND HDD MOTOR FABRICATED BY USING THE SAME - There are provided a sealing resin composition for a hard disk drive (HDD) motor and a HDD motor fabricated by using the same. The sealing resin composition includes: 45 to 65 parts by weight of urethane methacrylate resin; 35 to 50 parts by weight of methacrylate resin; and 2 to 4 parts by weight of acrylic acid. A sealing resin composition having a new composition is used as a sealing material of a FPC adhering part of the HDD motor, whereby a haze phenomenon due to air leak and outgas at the FPC adhering part may be improved and reliability of a HDD motor may be enhanced due to a reduction in generation of the outgas of the adhering part. | 06-27-2013 |
20130165356 | LUBRICATING OIL COMPOSITION FOR FLUID DYNAMIC BEARING AND HDD MOTOR FABRICATED USING THE SAME - There are provided a lubricating oil composition for a fluid dynamic bearing, and a HDD motor fabricated using the same. The lubricating oil composition includes an ester base oil and 0.01 to 3.00 parts by weight of an additive relative to 100 parts by weight of the base oil and has a density of 0.900 g/cm | 06-27-2013 |
20130165551 | ADHESIVE RESIN COMPOSITION FOR HDD MOTOR AND HDD MOTOR FABRICATED USING THE SAME - There are provided an adhesive resin composition for a HDD motor and a HDD motor fabricated using the same. The adhesive resin composition for a HDD motor includes: 25 to 35 parts by weight of a bisphenol E-epoxy resin; 10 to 25 parts by weight of an epoxy resin; 10 to 20 parts by weight of mercaptan; and 5 to 15 parts by weight of imidazole. The constituents of an epoxy adhesive material may be controlled, such that a curing speed may be increased, as compared to the case of the related art, thereby enhancing working efficiency and reliability. | 06-27-2013 |
20130259188 | REVERSE CONICAL LOWER END PLUG FOR AN ANNULAR NUCLEAR FUEL ROD - A lower end plug for an annular nuclear fuel rod includes a support with a great slenderness ratio, a coolant inflow part with an inner inflow space and a plurality of inflow holes in a wall thereof so as to interact with the inflow space, coupled to a lower end of the annular nuclear fuel rod at an upper end thereof, and extending from an upper end of the support in a reverse conical shape such that the inflow space interact with an inner channel of the annular nuclear fuel rod, and a coupler extending from a lower end of the support and coupled with a handing tool of the annular nuclear fuel rod. Thus, although a bottoming phenomenon of the annular nuclear fuel rod occurs, the coolant can be supplied to the inner channel of the annular nuclear fuel rod through the inflow holes of the lower end plug. | 10-03-2013 |