Abstract: A system for spraying liquid sodium onto impurities associated with liquid dip seals of nuclear reactors. The liquid sodium mixing with the impurities dissolves the impurities in the liquid sodium. The liquid sodium having dissolved and diluted the impurities carries the impurities away from the site thereby cleaning the liquid dip seal and surrounding area. The system also allows wetting of the metallic surfaces of the dip seal thereby reducing migration of radioactive particles across the wetted boundary.

Abstract: A method and apparatus for removing iodine-131 and iodine-125 from a liquid sodium reactor coolant. Non-radioactive iodine is dissolved in hot liquid sodium to increase the total iodine concentration. Subsequent precipitation of the iodine in a cold trap removes both the radioactive iodine isotopes as well as the non-radioactive iodine.

Abstract: A process for the insertion and exchange of the filter elements for suspended matter is performed from the clean-air-side. During the insertion of a filter element, a plastic tube (which encircles the circumference of the filter element and which exceeds in its length the layer thickness of the filter element several times) is tightly connected in its middle section with the side walls, which side walls form a border around the filter element; and then the open end of the plastic tube, which faces the frame, is connected by way of a tight fit with a ring, which is actually known and which surrounds the orifice of the frame into which the filter element is inserted. The filter element is connected with the frame by means of tightening devices, and the outer free end of the tube is turned inside out and around the filter element for the purpose of unhindered air passage through the filter layer, that during the exchange of the contaminated filter element, the outer open end of the tube is heat sealed.

Abstract: A recirculation system for use in pressurized water nuclear reactors to increase the output temperature of the reactor coolant, thereby achieving a significant improvement in plant efficiency without exceeding current core design limits. A portion of the hot outlet coolant is recirculated to the inlets of the peripheral fuel assemblies which operate at relatively low power levels. The outlet temperature from these peripheral fuel assemblies is increased to a temperature above that of the average core outlet. The recirculation system uses external pumps and introduces the hot recirculation coolant to the free space between the core barrel and the core baffle, where it flows downward and inward to the inlets of the peripheral fuel assemblies. In the unlikely event of a loss of coolant accident, the recirculation system flow path through the free space and to the inlets of the fuel assemblies is utilized for the injection of emergency coolant to the lower vessel and core.

Abstract: A system is disclosed for flushing the core of a nuclear reactor after a loss-of-coolant accident. A pump causes flow of liquid-phase fluid from the containment-vessel sump. This flow is used to provide the motivating force for an eductor that causes suction at the hot leg of the reactor. The eductor suction can draw gas-phase coolant out of the hot leg. As a result, it can reduce pressure which may be preventing the flow of liquid-phase coolant out of the hot leg. By causing liquid-phase flow through the reactor, the system ensures that particles and boric acid are flushed out of the core. The system thereby eliminates the build-up of particles and the concentrations of boric acid in the core that could result if the coolant were to leave the pressure vessel exclusively in the gas phase.

Abstract: In a blow-off device for limiting excess pressure in nuclear power plants, a condensation tube disposed so that a lower outlet end thereof is immersed in a volume of water in a condensation chamber having a gas cushion located in a space above the volume of water, and an upper inlet end of the condensation tube extends out of the volume of water and is connectible to a source of steam that is to be condensed or a steam-air mixture, the outlet end of the condensation tube being further provided with a base member at the mouth of the outlet end for limiting steam flows discharging in axial direction of the tube, and being formed with lateral openings subdividing the steam flow and bubbles produced in the volume of water, the lateral outlet openings being formed of slots widening toward the end of the condensation tube, the slots being distributed over the periphery of the outlet end of the condensation tube.

Abstract: The coolant gas of a gas-cooled high temperature nuclear reactor, structu components or the fuel elements of which are made predominantly of graphite, is circulated through a coolant circuit of the reactor and through a gas purification plant, and to further remove impurities from the coolant gas, carbon dust of colloidal particle size is fed into the coolant gas preferably on its passage back from the purification plant into the coolant circuit. The carbon dust may be monoatomic carbon or activated carbon, coke, carbon black or a mixture thereof. Preferably the coolant gas of the reactor is charged with the carbon dust before the reactor is initially started up and hot-run and the coolant gas charged with the carbon dust is circulated for a sufficiently long period to coat all metal surfaces in the coolant circuit with carbon dust before the initial starting up and hot-running takes place.

Abstract: Apparatus for baffling the flow of reactor coolant fluid into and about the core of a nuclear reactor. The apparatus includes a plurality of longitudinally aligned baffle plates with mating surfaces that allow longitudinal growth with temperature increases while alleviating both leakage through the aligned plates and stresses on the components supporting the plates.

Abstract: In a blow-off device for limiting excess pressure in nuclear power plants, at least one condensation tube disposed so that a lower outlet end thereof is immersed in a volume of water in a condensation chamber having a gas cushion located in a space above the volume of water, and the upper inlet end of the condensation tube extending out of the volume of water and being connectible to a source of steam that is to be condensed or a steam-air mixture, the outlet end of the condensation tube, for smoothing the condensation, being provided with wall parts forming passages extending in axial direction, delimited from one another and terminating in the water volume, the wall parts serving to subdivide steam flow from the source thereof and bubbles produced thereby in the water volume, the wall parts being constructed as a tube attachment and being formed with an opening corresponding to the outlet end of the condensation tube and by means of which the tube attachment is mounted on the outlet end of the condensation

Abstract: A pressurized-water reactor installation comprises a pressure vessel containing a core, a main reactor coolant system formed by one or more main coolant loops which are each formed by a steam generator and a main coolant pump and main coolant piping interconnecting the vessel, pump and generator. A pressurizer is connected with the coolant system to maintain a normal operating pressure on water in the loop and which prevents the water from boiling in the loop and pressure vessel. An emergency core cooling system is provided which includes a supply of emergency water and activating means responsive to a drop in the normal operating pressure in the loop, for automatically feeding the emergency water into the vessel to flood the core. In case the pump fails to operate, the pressure in the loop increases due to overheating of the water.

Abstract: In a nuclear reactor (e.g. one having coolant down-flow through a core to a hearth below) thermal insulation (e.g. of a floor of the hearth) comprises a layer of bricks and a layer of tiles thereon, with smaller clearances between the tiles than between the bricks but with the bricks being of reduced cross-section immediately adjacent the tiles so as to be surrounded by interconnected passages, of relatively large dimensions, constituting a continuous chamber extending behind the layer of tiles. By this arrangement, lateral coolant flow in the interbrick clearances is much reduced.The reactor core is preferably formed of hexagonal columns, supported on diamond-shaped plates each supported on a pillar resting on one of the hearth-floor tiles.

Abstract: An actuating mechanism for actuating electrical switches to insure coordinated connection of circuits vital to safe operation of a mass-transit vehicle includes a frame upon which are mounted one or more electrical switches. Also included is a cam rotatably mounted on the frame for actuating engagement with the switches upon rotation of the cam by key or similar device. The actuating mechanism further includes a toggle mechanism that is connected at one end to the frame and at the other end to the cam at a point spaced from the point of mounting of the cam to the frame. Secured to the toggle mechanism is a spring whose dead center position does not coincide with the point of actuating contact of the cam with the switch such that upon rotation of the cam, the spring resists movement of the cam until the dead center position of the spring is reached.

Abstract: An auxiliary cooling device for a primary fluid heat exchanger of a rapid neutron nuclear reactor, the exchanger having at least one nest of tubes in which there flows water to be heated to superheated steam and around whose tubes and inside whose casing there flows a liquid alkaline metal constituting the primary fluid. The casing of the exchanger is surrounded by a jacket having an air inlet tube and an air outlet tube at opposite ends. Inside the jacket there are auxiliary heat exchange surfaces such as spikes projecting from the casing of the primary heat exchanger proper. Application is to the absorption of residual power produced by a rapid neutron reactor after it is shut down.

Abstract: A personal security device incorporated into a conventional flashlight for informing a person, by remote control means, who is outside the door of the house, and indicating by a picture, whether it is a man, woman or child, the picture appearing on a view screen of a unit mounted on the flashlight, so that a person is thus cautioned against opening the door, particularly if there is a man outside.

Abstract: A combined baggage rack and overhead light assembly for attachment to an interior wall of a vehicle includes a pair of parallel support arm assemblies extending outwardly away from the wall for receiving a grill which provides the baggage rack. An elongated overhead light fixture housing is connected below the baggage rack and includes a pair of elongated tracks having an elongated opening therebetween to receive a plurality of light fixtures. The light fixtures are adapted to be moved on the tracks to different desired positions, dependent upon the seating arrangement in the vehicle, prior to securing them in place on said tracks. Panels of predetermined lengths are placed between adjacent pairs of light fixtures after fixtures are secured in place.

Abstract: A dispersement apparatus for an enlarged mass of fissionable material which causes the liquid fissionable material to move by gravity into a first passage means, the first passage means being connected to a plurality of second passages with the fissionable material separating into the second passages, each second passage being connected to a plurality of third passages which results in the liquid fissionable material being further separated. Each of the passages will contain adjacent the junction thereof with the previous passage a quantity of low melting point material, such as lead or tin. The heat of reaction of the fissionable material will readily melt this meltable material prior to entering the passage. The free end of the third passage may extend within a sand base with explosive means being located therewith to further and ultimately very finely disperse the fissionable material.

Abstract: A flow baffling arrangement for the core of a nuclear reactor. A plurality of core formers are aligned with the grids of the core fuel assemblies such that the high pressure drop areas in the core are at the same elevations as the high pressure drop areas about the core periphery. The arrangement minimizes core bypass flow, maintains cooling of the structure surrounding the core, and allows the utilization of alternative beneficial components such as neutron reflectors positioned near the core.

Abstract: Limit switch, particularly for use as a lock switch for safety belts, composed of a flat housing, spaced contact elements in the housing, a switching lever formfittingly secured on one side of the housing with the other side free to move, a spring-loaded switch element on the free end of the lever to open and close the contacts, the side wall of the housing acting as a stop to limit movement of the lever, a cover with an opening for the housing, and a tripping pin attached to the lever extending through the opening, which pin is activated by for example closing a seat belt by a sliding tongue inserted in the housing thus moving the switch element to open or close the contacts.

Abstract: Rupture protection device for hollow cylindrical members having, in installed condition thereof, respective projections at the axial ends thereof protruding beyond the diameter thereof and forming axial stops, includes a plurality of rings serially connectible to one another in axial direction of a hollow cylindrical member and slideable onto the hollow cylindrical member together with at least one divided filler ring so as to form a closed ring unit covering the hollow cylindrical member, the rings being formed with respective overlapping zones at adjoining end face regions thereof constituting respective encircling projections and recesses complementary thereto in mutual engagement and respectively overlying and underlying one another, the filler ring being at least bipartite and formed with both end face regions thereof having encircling projections overlying respective recesses formed in the rings adjoining the filler ring so as to facilitate insertion of the filler ring radially on a hollow cylindrical m

Abstract: In a blow-off device for limiting excess pressure in nuclear power plants, at least one condensation tube disposed so that a lower outflow end thereof is immersed in a volume of water in a condensation chamber having a gas cushion located in a space above the volume of water, and an upper inflow end of the condensation tube extends out of the volume of water and is connectible to a source of steam that is to be condensed or a steam-air mixture, the outflow end of the condensation tube, for stabilizing the condensation being provided with an assembly of wall parts forming passageways extending in axial direction for subdividing the steam flow and bubbles produced in the volume of water, the passageways of the assembly of wall parts being stepped in axial direction at both axial ends of the assembly of wall parts.