Abstract: Hydraulic jacks are arranged radially both inside and outside the confinement chamber (EC), substantially on a level with the center of gravity of the boiler (BV, EA) disposed inside. The inside jacks transmit thrust to the boiler via an annular floor (20). The outside jacks transmit thrust to the walls (M) of the hall. The outside jacks are arranged as energy-absorbing dampers. The inside and outside jacks resist fast compression by means of calibrated fluid flow orifices, while they expand readily by means of one way valves and pressure accumulators. The boiler and the confinement chamber stand on a base that is resiliently movable in a horizontal direction relative to the raft (R) of the building. This ensures that the reactor is returned to its normal position once an earthquake is over.

Abstract: A combustion system comprising a tubular structure having an upstream end and defining within it a longitudinal passage. A tubular wall surrounding the structure and defining with the structure a further longitudinal passage, of annular cross section. The tubular structure having longitudinally extending, circumferentially spaced staves and longitudinally spaced coaxial hoops for the passage of fluid, the hoops being shaped to deflect substantially axially flowing fluid either inwards or outwards through the openings for discharge either inside or outside the assembly respectively.

Abstract: The hydraulic drive mechanism comprises an hydraulically actuated rod drive mechanism that cooperates with a pivotable latching mechanism. The pressurized reactor coolant is utilized to raise the drive rod into contact with and to pivot the latching mechanism so as to allow the drive rod to pass the latching mechanism. The pressure in the housing is then equalized which allows the drive rod to move downwardly into contact with the latching mechanism but remain in a raised position with respect to the reactor core. Once again, the reactor coolant pressure may be utilized to raise the drive rod and thus pivot the latching mechanism so that the drive rod passes above the latching mechanism. Again, the mechanism pressure can be equalized which allows the drive rod to fall and pass by the latching mechanism so that the drive rod approaches the reactor core.

Abstract: A control system for rolling airframes utilizing variable pitch control surfaces includes a variable inertia device within the control system connected to the servo control motors that control the control surfaces, with the variable inertia device selectively controllable to optimize the inertia of the control system for optimizing the power requirements of the control system. The variable inertia means includes a rotatable mass with means for moving the effective position of the mass radially inwardly and outwardly from the rotary shaft of the control system for selectively varying the inertia of the control system.

Abstract: A mechanically attached load pad for the duct of a liquid metal nuclear reactor fuel assembly.

Abstract: A support structure for a nuclear reactor is disclosed comprising a primary support element connected with the roof of the pressure vessel and a secondary support element joined with the primary support element. The thermal roof shield and the roof reflector are connected to the secondary support element.

Abstract: A getter-lubricant coating system between the nuclear fuel and the fuel cladding minimizes the pellet-clad stress concentration and renders fission gases and impurities unreactive to the cladding. The getters are matched to the lubricant matrix such that they are homogeneously dispersed in the matrix and are physically and/or chemically bound in place. A preferred form of the getter is a graphite or boron nitride intercalate of the getter material.

Abstract: A device for securing a fuel assembly to a nuclear reactor pressure vessel comprises upper and lower tie plates for supporting the fuel assembly at its lower and upper ends, spacers for supporting the fuel assembly at intermediate portions between the both tie plates, a channel box surrounding the fuel assembly, and a stationary handle attached to the upper tie plate. A movable handle is attached to the stationary handle to be vertically slidable with respect thereto and the movable handle is always urged downwardly by a coil spring. Hook members are connected to the stationary handle to be rotatable in accordance with vertical movement of the movable handle such that the lower end of the hook member engages with an upper grid of the pressure vessel when the movable handle is lowered to a low portion and disengages therefrom when the movable handle is lifted to an upper position.

Abstract: Apparatus for superheating steam. In accordance with one aspect of the invention, the apparatus is provided with two banks of inclined tubes extending upwardly from an outlet header to respective inlet headers. The banks of tubes are disposed in the flow path of main steam through the apparatus and provide a flow of vapor for adding superheat to the main steam. In accordance with another aspect of the invention, the tubes extend upwardly to closed ends whereby a lower header acts as both a vapor inlet and condensate outlet. In accordance with another aspect of the invention, the vapor is provided by a fossil fuel-fired vapor generator to superheat main steam which has been provided by a nuclear steam generator.

Abstract: A fuel assembly for a boiling water reactor is provided with at least one vertical water channel (4, 5) for a by-pass flow through the fuel assembly. At its lower end the channel is connected to a radial tube (10) which opens out at the outer side surface of the fuel assembly. Below the radial tube, the wall of the assembly base (2) is provided with a through-hole (12).

Abstract: Fuel assembly having square cross-section and a plurality of tube elements (7,8) arranged in a square reactor lattice, at least one of said tube elements being water tubes (8) and a predominant number being fuel rods (7). Each fuel channel wall has a hollow projection (9) lying in a vertical mid-plane. The number of tube elements between two projections (9) lying in the same mid-plane is smaller than nine and greater than two. A plurality of rows of nine tube elements (7, 8) are arranged in parallel with each of the mid-planes.

Abstract: A fly trap for capturing umbilical plugs ejected radially outwardly from a missile during the initial portion of the launch, the fly trap comprises impact and retention arms and a ratchet and compression spring which cooperate with a housing to allow the arms to only rotate a limited amount to retain the plug within the arms and prevent it from rebounding into the missile as the missile accelerates in the launch tube.

Abstract: Fuel assembly for a nuclear reactor comprising at least two guide tubes (6) made of a material metallurgically compatible with the material of the spacer grids (9, 10). The guide tubes (6) are fixed rigidly to the plates (8) and to the spacer grids (9, 10). The other guide tubes (7), made of a material with a low neutron capture cross section, are secured to only one of the end plates and are movably engaged in the cells of the spacer grids (9, 10) so as to be able to move with respect to these under the effect of expansion.The invention is particularly applicable to pressurized water nuclear reactors.

Abstract: A grid of a fuel assembly structure for a nuclear reactor comprises two sets of uniformly spaced straps perpendicular to each other for receiving and supporting cylindrical sleeves. The straps forming cells which receive the sleeves have notches at their edges, and the sleeves are joined to the straps by lap welding at the notches.

Abstract: A quick opening hatch for use on a transfer tube of a nuclear reactor plant that is adapted to replace the conventional hatch on the transfer tube. A locking ring is provided with a plurality of screw openings that is adapted for connection to the transfer tube, and a hatch cover fitably received within the locking ring for closing-off the transfer tube. To lock the cover to the ring, latches are movably connected with the cover for locking engagement with the locking ring, and a sprocket with a plurality of crank arms is movably connected with the cover and the latches for movement thereof into locking engagement with a latch housing on the locking ring for locking the cover to the ring and out of engagement with the latch housing for releasing the cover from the locking ring so as to permit removal of the hatch cover from the locking ring to provide access to the transfer tube.

Abstract: In an ejection cavity defined by walls such as (753 and 754), an open decoy support body (70) in the form of a slide is placed, and equipped with a pyrotechnic ejection charge (709) and a transmitter (761) for igniting the ejection charge on command. In addition to the stopper (755) which closes the ejection orifice of the cavity, a retaining member (750) is provided, comprising along its edge V-shaped clips (751), whereof the point is directed towards the inside of the decoy launching cavity and keeps the decoys in place despite the high accelerations and vibrating stresses encountered in an aircraft. At the time of deployment of the decoy, the sliding of the slide will disengage the V-shaped clips (751), which allows a slow departure of the decoy support member.

Abstract: A fine-motion control rod drive for a nuclear reactor, which can be disassembled in sections. The drive includes a spindle defining a sealing surface to prevent spillage after the drive motor is removed. A spline connection with a sliding key arrangement permits the shaft of the drive motor to be separated from the spindle during disassembly. The drive motor is effective for uncoupling the control rod drive piston from the control rod prior to disassembly.

Abstract: A vacuum actuator having a vacuum chamber and an atmospheric chamber separated from each other by means of a diaphragm, and an actuator rod connected at its one end to the diaphragm and extending across the atmospheric chamber to the outside of the actuator so as to be connected to an object to be actuated. An annular solenoid coil is mounted on the upper surface of the upper wall of the case defining the vacuum chamber, in such a manner that the axis of the solenoid coil extends substantially at a right angle to the axis of the actuator rod. A plunger disposed in the annular solenoid coil is adapted to be moved in one and the other directions along the axis of the annular solenoid coil. The end of the plunger is adapted to be moved into and out of a valve case in which is defined a control pressure chamber.

Abstract: Apparatus for transferring, not only the fuel assemblies, but other component assemblies including control-rod assemblies, thimble-plug assemblies, poison assemblies and the like during refueling of a nuclear reactor. The apparatus includes an outer mast for guiding and protecting the component assemblies which are transferred, an inner mast movable vertically within the guiding mast. The inner mast has grippers for engaging and lifting or lowering fuel assemblies. The outer mast has internal grooved rollers along its length. The inner mast is formed at oppositely facing channels held in a rigid assembly by plates to which the channels are secured. Opposite corners formed by the flanges and the webs of the channels penetrate into the grooves of the rollers and the inner mast is guided and held in position by the rollers. The apparatus also includes an elongated tube within the inner mast movable vertically relative to the inner mast.

Abstract: This invention relates to a pump arrangement (54) for use in a linear fluid operated device having a reciprocating piston (14) separating a first active fluid chamber (30) and a second chamber (32) which eliminates the problem associated with fluid leakage buildup developing in the second chamber. The pump arrangement (54) is connected to the reciprocating piston (14) and pumps leakage fluid present in the second chamber (32) from the second chamber (32) and into the first chamber (30) in response to a force of a preselected minimum magnitude being applied to the pump arrangement (54). Thus, the problems of inefficient linear fluid operated device operation, reduced piston stroke length, external fluid leakage, and erratic piston travel speed are eliminated. The pump arrangement (54) is particularly suited for use in a single acting linear hydraulic jack (12) such as used on a material handling vehicle.