Abstract: A calibration system is disclosed. The calibration system includes a waveform generator configured to generate a periodic waveform and a control circuit in signal communication with the waveform generator. The control circuit includes an analog-to-digital converter configured to convert the periodic waveform to digital values and an electronic device in signal communication with the analog-to-digital converter. The electronic device is configured to verify calibration of (1) timing of the control circuit and (2) voltage levels of the control circuit based on the periodic waveform.

Abstract: Welds made by pulses of laser energy are evaluated on-line by analyzing light emitted from the weld site during application the laser pulses. The pulses of light from the weld site are compared with base pulses generated from a good weld, and are used to calculate parameters such as heat-up rate and peak temperature which in turn, are analyzed to determine weld quality. For use in welding in confined spaces such as heat exchange tubes, and particularly the tubes in a PWR steam generator, a single optic fiber delivers the laser energy pulses to the weld site and transmits light from the weld site back to a splitter which diverts it to detectors for conversion to electrical signals used to generate a graphical display.

Abstract: Refueling apparatus for a nuclear reactor including a bridge and a trolley. The bridge is moveable in tracks along the containment of the pit in which the reactor is immersed in water and the trolley moveable in tracks on the bridge at right angles to the tracks on the bridge. The trolley carries a mast assembly for engaging, raising, and lowering a nuclear-reactor component assembly involved in the refueling. The mast includes an elongated member for engaging control-rod and thimble plug assembly and a gripper for raising fuel assemblies. The elongated member is moveable upwardly or downwardly.A TV camera and a light source and reflector are mounted on the gripper assembly at the lower end of the mast assembly. The source and reflector illuminate a selected part of the fuel assembly which is to be transferred and the camera is directed to this part so as to pick up an image of this part. The cooperative TV-receiver monitor on the console on the trolley is provided with cross hairs.

Abstract: Refueling apparatus for a nuclear reactor including a bridge and a trolley movable at right angles to each other over a pit. The trolley carries a mast assembly for engaging, raising, lowering reactor component assemblies.The mast assembly carries electric cables and compressed air hoses from electric and air driven components on the mast and is rotatable relative to the trolley. The cables and hoses are passed from the mast assembly through a flexible cable tray which is oriented with its cable-carrying slot vertically in the configuration generally of an S. The cable tray is connected to the mast at one of its ends, is partly wound around the mast from that end and departs from the mast a predetermined distance at the opposite end. The tray remains fixed at the opposite end as it is wound on or unwound from the mast, so that the cables and hoses as they pass from the opposite end to electrical and air terminals as the trolley remains anchored at the opposite end.

Abstract: A remotely operated device which attaches to an existing internals lifting rig to safely lift and transport nuclear reactor internals structures. The device includes a grapple assembly uniquely formed to maximize the effective bearing surface of an annular shoulder disposed on the grapple assembly to engage the internal structure. The annular shoulder comprises a first outer diameter, the annular shoulder defining a second outer diameter disposed thereabove. The grapple assembly comprises a plurality of fingers circumferentially disposed about an actuator rod which has a diameter essentially equal to a first inner diameter of the grapple assembly. The lower end of the grapple assembly has a second inner diameter smaller than the first and axially adjacent to the annular shoulder.

Abstract: A nuclear reactor containment arrangement has a permanent cavity ring seal extending across an annular expansion gap between a reactor pressure vessel and a containment wall to provide a water tight seal therebetween. The annular ring seal has a support ring with an inner downwardly extending cylindrical section resting on the reactor flange and an outer downwardly extending cylindrical section resting on a shelf in the containment wall. A vertically extending, L-shaped, seal extends between an inner end of the support ring while a vertically extending, L-shaped, seal extends between the outer cylindrical section and the containment wall shelf. Neutron shielding material is suspended, by support rods, within the annular expansion gap while thermal insulation is provided therebelow. Manways and ports in the support ring are sealed by hatches and provide access to the annular expansion gap and, while open, provide for flow of cooling air from the annular expansion gap through the support ring.

Abstract: An annular seal ring between a reactor pressure vessel and a containment wall is disposed in an annular expansion gap therebetween, having a support ring and inner and outer upwardly extending cylindrical sections. The inner cylindrical section is disposed below a flange on the reactor and has a flexible seal therebetween, while the outer cylindrical section terminates substantially parallel and spaced from a shelf in the containment wall with a flexible seal therebetween. The annular seal ring is supported by radial support beams, while support rods depending from the support ring position neutron shielding material in the annular expansion gap. Manways and ports provide access to the gap and thermal insulation is provided below the neutron shielding material to direct cooling air from the annular gap up through opened manway and port.

Abstract: A system for transferring fuel assemblies in a nuclear reactor includes a load control system which compares the current load to the more restrictive of fixed overload and underload limits, and instantaneous overload and underload limits continuously calculated from a running average of the measured load. Operation of the refueling machine is terminated if any of these limits are exceeded. The system also accommdates for changes in buoyancy and tension loading applied by spring loaded reels for pneumatic hoses and electrical cables servicing the gripper which engages the fuel assembly as the mast supporting the fuel assembly is raised and lowered in the pool of shielding water covering the reactor core. The current and recent suspended load measurements are displayed relative to the fixed and instantaneous overload and underload limits on a graphic display along with speed and other pertinent data.

Abstract: Refueling apparatus for a nuclear reactor including a bridge and a trolley. The bridge is moveable in tracks along the containment of the pit in which the reactor is immersed in water and the trolley moveable in tracks on the bridge at right angles to the tracks on the bridge. The trolley carries a mast assembly for engaging, raising, lowering a nuclear-reactor component assembly involved in refueling. The mast includes an elongated member for engaging control-rod and thimble plug assembly and a gripper for raising fuel assemblies. The elongated member is moveable upwardly or downwardly.The bridge, trolley and mast assembly each has a pulse generator which produces pulses in accordance with the movement of each. The number of pulses produced when the bridge, trolley or elongated member move to a position at a predetermined distance from a reference position is a measure of the new position of each.

Abstract: The responses of a nuclear reactor refueling machine to commands from a detachable control console are simulated to allow operation of the console for testing and operator training with the console removed from the machine. A simulator, which is connected to the console by the same input and output leads which normally connect the console to the refueling machine, includes a single pulse generator driven by a single three phase A-C motor to simulate movement of the refueling machine bridge, trolley and hoist. The motor drive signals generated on separate console output leads are all connected to the single simulator motor, while the brake release signals energize relays which switch the pulse signals generated by the single pulse generator to the console input leads corresponding to the selected refueling machine component drive motor.

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: A refueling machine for inserting and removing fuel assemblies from a nuclear reactor including a pair of concentrically disposed stationary masts mounted on a movable bridge which spans the containment walls of the reactor. The bridge supports a trolley movable transversely to bridge movement thus providing an arrangement wherein the masts can be precisely positioned over a fuel assembly in the reactor core. A hoist mounted on the outer of the masts supports a vertically movable inner mast of a size sufficient to enclose a fuel assembly. An actuator tube inside the inner mast moves gripper fingers on the bottom thereof into engagement with the top nozzle of a fuel assembly prior to lifting it upwardly out of the reactor core.