Patents by Inventor Krishna P. Singh

Krishna P. Singh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10991472
    Abstract: A neutron absorbing insert for use in a fuel rack. In one aspect, the insert includes: a plate structure having a first wall and a second wall that is non-coplanar to the first wall; the first and second walls being formed by a single panel of a metal matrix composite having neutron absorbing particulate reinforcement that is bent into the non-coplanar arrangement along a crease; and a plurality of spaced-apart holes formed into the single panel along the crease prior to bending.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: April 27, 2021
    Inventors: Evan Rosenbaum, Thomas G. Haynes, III, Krishna P. Singh
  • Publication number: 20210118586
    Abstract: A nuclear waste cask with impact protection includes impact limiters detachably coupled to opposite ends of the cask. Each impact limiter may comprise a deformable energy-absorbing perforated sleeve of cylindrical shape comprising an array of closely-spaced longitudinally elongated perforations. The perforations may comprise longitudinal passages having a circular cross-sectional shape in certain embodiments. The perforated sleeve may have an annular metallic body of monolithic unitary structure in which the perforations are formed and a central opening to receive the ends of the cask therein. When exposed to external impact forces such as created by dropping the cask, the perforations collapse inwards in the impact or crush zone to absorb the energy of fall while preventing or minimizing any forces transmitted to the cask to maintain the integrity of waste containment barrier.
    Type: Application
    Filed: October 2, 2020
    Publication date: April 22, 2021
    Applicant: HOLTEC INTERNATIONAL
    Inventors: Krishna P. SINGH, Charles W. BULLARD, II, Xuejun ZHAI
  • Publication number: 20210082590
    Abstract: A neutron absorbing insert for use in a fuel rack. In one aspect, the insert includes: a plate structure having a first wall and a second wall that is non-coplanar to the first wall; the first and second walls being themed by a single panel of a metal matrix composite having neutron absorbing particulate reinforcement that is bent into the non-coplanar arrangement along a crease; and a plurality of spaced-apart holes formed into the single panel along the crease prior to bending.
    Type: Application
    Filed: March 25, 2014
    Publication date: March 18, 2021
    Applicant: Holtec International, Inc.
    Inventors: Evan Rosenbaum, Thomas G. Haynes, III, Krishna P. Singh
  • Patent number: 10950361
    Abstract: An underground ventilated system for storing nuclear waste materials. The system includes a storage module having an outer shell defining an internal cavity and an inner shell. A majority of the height of the outer shell may be disposed below grade. The outer shell may include a hermetically sealed bottom. First and second canisters are positioned in lower and upper portions within the cavity respectively in vertically stacked relationship. A centering and spacing ring assembly is interspersed between the first and second canisters to transfer the weight of the upper second canister to the lower first canister. The assembly may include centering lugs which laterally restrain the first and second canisters in case of a seismic event. A natural convection driven ventilated air system cools the canisters to remove residual decay heat to the atmosphere. In one non-limiting embodiment, the shells are made of steel.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: March 16, 2021
    Assignee: HOLTEC INTERNATIONAL
    Inventor: Krishna P. Singh
  • Publication number: 20210074444
    Abstract: A method of retrofitting a spent nuclear fuel system with a neutron absorbing apparatus. The method includes inserting a neutron absorbing apparatus into a first cell of an array of cells each configured to hold a spent nuclear fuel assembly. The neutron absorbing apparatus includes a first wall and a second wall supported by a corner spine to form a chevron shape and a first locking tab protruding outwardly from the first wall towards a first cell wall of the first cell. The method includes cutting a half-sheared second locking tab in the first cell wall of the first cell adjacent to and above the first locking tab of the neutron absorbing apparatus. Finally, the second locking tab is positioned to locking engage the first locking tab to retain the neutron absorbing apparatus in the first cell during removal of one of the fuel assemblies from the first cell.
    Type: Application
    Filed: November 4, 2020
    Publication date: March 11, 2021
    Inventors: Krishna P. SINGH, Stephen J. AGACE, Stephen E. THOMPSON, John D. GRIFFITHS, Richard M. SPRINGMAN, Charles W. BULLARD, II, P. Stefan ANTON
  • Patent number: 10939787
    Abstract: An apparatus, system and method for handling and translating high level radioactive waste. The apparatus comprises a body for supporting the cask close to the ground so that the cask and the apparatus can pass underneath over head doors. The apparatus further comprises rollers for translating the cask. The apparatus additionally supports the storage cask during spent nuclear fuel transfer procedures.
    Type: Grant
    Filed: June 17, 2019
    Date of Patent: March 9, 2021
    Assignee: HOLTEC INTERNATIONAL
    Inventor: Krishna P. Singh
  • Publication number: 20210057118
    Abstract: An apparatus for supporting spent nuclear fuel including a plurality of wall plates arranged in an intersecting manner to define a basket apparatus extending along a longitudinal axis. The basket apparatus may include a plurality of fuel cells and a plurality of flux traps between adjacent fuel cells. A plurality of reinforcement members may be positioned in the flux traps and may extend between opposing ones of the wall plates that form the flux traps. Each of the wall plates may be a slotted wall plate. The slotted wall plates may be interlocked with one another to form the basket apparatus. Each of the slotted wall plates may include an upper edge, a lower edge, and a plurality of plate slots formed in each of the upper and lower edges. The plate slots of the slotted wall plates may receive intersecting slotted wall plates.
    Type: Application
    Filed: October 27, 2020
    Publication date: February 25, 2021
    Inventors: Krishna P. SINGH, P. Stefan ANTON, Richard M. SPRINGMAN, Robert MAHORTER
  • Publication number: 20210053124
    Abstract: Described herein are methods of forming a neutron shielding material. Such material may comprise a powder blend comprising a first component comprising a blend of a first metal particle and a first ceramic particle; and a second component comprising a reinforcing chip, the reinforcing chip comprising a second ceramic particle dispersed within a chip metal matrix.
    Type: Application
    Filed: October 29, 2020
    Publication date: February 25, 2021
    Inventors: Krishna P. Singh, Thomas G. Haynes, III, Luke Chester Sobus
  • Publication number: 20210057120
    Abstract: A containment enclosure for shielding an outer cask containing an inner canister loaded with nuclear waste such as spent fuel rods. The enclosure includes a lower base portion at least partially embedded in a concrete pad and an upper radiation shielding portion defined by a shield jacket coupled to and supported by the lower base portion at a circumferential joint. Cavities of the base and shielding portions collectively define a contiguous containment space for the cask. A portion of the cask resides in each of the base and shielding portions which completely enclose and shield the cask to minimize radiation dosage of personnel in the environment surrounding the cask. The cask is cooled by a natural convectively-driven ambient cooling air ventilation system including air inlets at the circumferential joint of the enclosure. The concrete pad may be part of a spent nuclear fuel storage installation comprising plural cask containment enclosures.
    Type: Application
    Filed: August 24, 2020
    Publication date: February 25, 2021
    Applicant: HOLTEC INTERNATIONAL
    Inventor: Krishna P. SINGH
  • Publication number: 20210046569
    Abstract: An automated welding system for sealing high level radioactive waste containers in the field at the nuclear plant site. The system includes a programmable portable robotic welder comprising a multi-jointed articulating robotic arm. A welding head operable to form a weld is mounted to the arm. Operation of the robotic welder and ancillary components is controlled by a programmable controller which implements a welding plan. In one embodiment, a circumferentially-extending lid-to-shell hermetic seal weld may be formed by the robotic welder. The weld is completed in multiple welding passes through the weld joint between the lid and shell guided by an automated joint tracking sensor linked to the controller. The highly portable robotic welder is detachably mountable on the lid to perform the welding. An automated pivotable cable-conduit management apparatus keeps electrically conductive wiring and flow tubing out of the path of the rotating robotic arm during welding.
    Type: Application
    Filed: August 17, 2020
    Publication date: February 18, 2021
    Applicant: HOLTEC INTERNATIONAL
    Inventors: Krishna P. Singh, Brian Farnsworth
  • Publication number: 20210050122
    Abstract: A nuclear reactor system that, in one embodiment, utilizes natural circulation to circulate a primary coolant in a single-phase through a reactor core and a heat exchange sub-system. The heat exchange sub-system is located outside of the nuclear reactor pressure vessels and, in some embodiments, is designed so as to not cause any substantial pressure drop in the flow of the primary coolant within the heat exchange sub-system that is used to vaporize a secondary coolant. In another embodiment, a nuclear reactor system is disclosed in which the reactor core is located below ground and all penetrations into the reactor pressure vessel are located above ground.
    Type: Application
    Filed: July 28, 2020
    Publication date: February 18, 2021
    Inventors: Krishna P. Singh, P. Stephan Anton, Ranga Nadig, Indresh Rampall
  • Patent number: 10923239
    Abstract: An entire nuclear fuel core comprising a plurality of fuel assemblies is preassembled in a nuclear fuel cartridge having a self-supporting unitary support structure. During a refueling operation, the unitary support structure is moved into a nuclear reactor vessel. The unitary support structure may be formed by top and bottom core plates coupled together by vertically-oriented connecting rods which compress the fuel assemblies therebetween. A plurality of reflector wall segments circumscribe the core and are the coupled together between the core plates by the connecting rods which are coupled to the core plates. The connecting rods may extend through the wall segments.
    Type: Grant
    Filed: November 27, 2017
    Date of Patent: February 16, 2021
    Assignee: SMR INVENTEC, LLC
    Inventors: Krishna P. Singh, P. Stefan Anton, Peter Stefanovic
  • Publication number: 20210031315
    Abstract: A vertical bundle air-cooled heat exchanger, a finned tube assembly for an air cooled condenser and method for forming the same, and a system for removing thermal energy generated by radioactive materials. In one aspect, an air cooled condenser sized for industrial and commercial application includes an inlet steam distribution header for conveying steam, a condensate outlet header for conveying condensate, an array of tube bundles each having a plurality of finned tube assemblies having a bare steel tube with an exposed outer surface and a set of aluminum fins brazed directly onto the tube by a brazing filler metal. The steel tubes may be spaced apart by the aluminum fins and have an inlet end fluidly coupled to the inlet steam distribution header and an outlet end fluidly coupled to the outlet header. A forced draft fan may be arranged to blow air through the tube bundles.
    Type: Application
    Filed: October 19, 2020
    Publication date: February 4, 2021
    Inventors: Krishna P. SINGH, Joseph Gerald Leo RAJKUMAR, Indresh RAMPALL, Frank David SANDERLIN, William G. SCHOLFIELD, Dmitriy Yakov KATS, Joseph Paul MOSHER, Robert Charles SLOAN, Thomas G. HAYNES, III
  • Patent number: 10910119
    Abstract: A neutron absorber apparatus for use in restoring reactivity control to a nuclear fuel rack. The apparatus comprises an elongated tubular insert assembly configured for insertion in a storage cell of the rack. First and second absorber plates, each formed of a boron-containing material, are coupled together by upper and lower stiffening bands at the insert extremities and form a longitudinally-extending cavity configured for receiving a fuel assembly. The absorber plates and stiffening bands may have a rectilinear cross sectional configuration in one embodiment. At least one elastically deformable locking protrusion mounted proximate to the lower end of the absorber plates lockingly engages an available lower edge disposed in the cell sidewall above its bottom end. This fixes the tubular insert axially in the cell, thereby preventing its withdrawal after installing the insert. In one embodiment, the edge may be the bottom of existing absorber sheathing in the cell.
    Type: Grant
    Filed: July 17, 2019
    Date of Patent: February 2, 2021
    Assignee: HOLTEC INTERNATIONAL
    Inventors: Krishna P. Singh, Stephen J. Agace
  • Publication number: 20210012913
    Abstract: A nuclear reactor cooling system with passive cooling capabilities operable during a loss-of-coolant accident (LOCA) without available electric power. The system includes a reactor vessel with nuclear fuel core located in a reactor well. An in-containment water storage tank is fluidly coupled to the reactor well and holds an inventory of cooling water. During a LOCA event, the tank floods the reactor well with water. Eventually, the water heated by decay heat from the reactor vaporizes producing steam. The steam flows to an in-containment heat exchanger and condenses. The condensate is returned to the reactor well in a closed flow loop system in which flow may circulate solely via gravity from changes in phase and density of the water. In one embodiment, the heat exchanger may be an array of heat dissipater ducts mounted on the wall of the inner containment vessel surrounded by a heat sink.
    Type: Application
    Filed: May 26, 2020
    Publication date: January 14, 2021
    Applicant: SMR Inventec, LLC
    Inventors: Krishna P. Singh, Joseph Rajkumar
  • Publication number: 20210012915
    Abstract: A method of storing high level radioactive waste, and specifically a method of adjusting or controlling the temperature of ventilation air flowing through a storage cavity of a ventilated system. The method includes positioning a metal canister containing high level radioactive waste in a storage cavity of the ventilated system. The ventilated system includes a cask body, a cask lid, a plurality of inlet ducts, and at least one outlet duct so that ventilation air can flow from atmosphere into the storage cavity where it is heated and then back out to the atmosphere. The method includes progressively reducing a cross-sectional area of one or more of the inlet ducts and/or the outlet duct over time so that a rate at which the ventilation air is heated within he storage cavity is maintained above a predetermined threshold to mitigate the risk of stress corrosion cracking in the metal canister.
    Type: Application
    Filed: June 12, 2020
    Publication date: January 14, 2021
    Applicant: HOLTEC INTERNATIONAL
    Inventor: Krishna P. Singh
  • Patent number: 10892063
    Abstract: A module for storing high level radioactive waste includes an outer shell, having a hermetically closed bottom end, and an inner shell forming a cavity and being positioned inside the outer shell to form a space therebetween. At least one divider extends from the top to the bottom of the inner shell to create a plurality of inlet passageways through the space, each inlet passageway connecting to a bottom portion of the cavity. A plurality of inlet ducts each connect at least one of the inlet passageways and ambient atmosphere, and each includes an inlet duct cover affixed atop a surrounding inlet wall, the inlet wall being peripherally perforated. A removable lid is positioned atop the inner shell and has at least one outlet passageway connecting the cavity and the ambient atmosphere, the lid and the top of the inner shell being configured to form a hermetic seal therebetween.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: January 12, 2021
    Assignee: HOLTEC INTERNATIONAL
    Inventor: Krishna P. Singh
  • Patent number: 10878973
    Abstract: A passively cooled storage module for spent nuclear fuel includes an elongated body including a top end, bottom end, sidewall, baseplate, detachable lid, and cavity for holding a fuel canister containing heat-emitting spent nuclear fuel assemblies. Cooling air inlet ducts spaced draw ambient cooling air radially inwards into a lower portion of the cavity. The air flows upwards in the cavity along the canister and is discharged from the top end of the module to atmosphere via natural circulation. The air inlet ducts may have a multi-angled and recurving configuration comprising one or more obliquely angled sections in one embodiment. The exterior inlet end openings of the inlet ducts are arranged at a higher elevation than the interior outlet end openings to prevent the ingress of standing and flood-related waters. The ducts and lid include radiation shielding features.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: December 29, 2020
    Inventors: Krishna P. Singh, Paul Stefan Anton
  • Patent number: 10872707
    Abstract: A dry storage systems for radioactive nuclear waste materials in one embodiment includes a canister having a tubular shell defining an internal cavity for storing nuclear waste material, a lid sealably welded to one end the shell, and an end closure attached to a second end of the shell. The end closure includes a base plate having an upturned peripheral annular closure flange. In one embodiment, a circumferentially-extending butt joint is formed between the closure flange and the shell second end which is hermetically seals by a full through-wall thickness butt weld. Various embodiments may further include secondary pressure retention barriers enclosing the canister or select portions thereof most susceptible to failure under certain conditions.
    Type: Grant
    Filed: October 17, 2016
    Date of Patent: December 22, 2020
    Inventor: Krishna P. Singh
  • Patent number: 10867714
    Abstract: A fuel storage system for storing and drying nuclear fuel rods includes a vertically oriented capsule defining an internal cavity. A plurality of fuel rod storage tubes is disposed in the cavity. In one embodiment, each storage tube has a transverse cross section configured and dimensioned to hold no more than one fuel rod. Intact or damaged fuel rods may be stored in the storage tubes. After the fuel rods are loaded into the capsule, a lid is attached to a previously open top end of the capsule. In one embodiment, the lid may be sealed welded to the capsule for forming a gas tight enclosure. The interior of the capsule and multiple fuel rods contained therein may be dried together simultaneously via flow conduits formed in the lid that can be fluidly connected to a suitable drying process such as a forced gas dehydration system.
    Type: Grant
    Filed: May 2, 2019
    Date of Patent: December 15, 2020
    Inventors: Richard M. Springman, Stephen J. Agace, Krishna P. Singh