Abstract: An advanced overfire air system for NO.sub.x control designed for use in a firing system of the type that is particularly suited for use in fossil fuel-fired furnaces and a method of operating such a furnace which embodies an advanced overfire air system. The advanced overfire air system for NO.sub.x control includes multielevations of overfire air compartments consisting of a plurality of close coupled overfire air compartments and a plurality of separated overfire air compartments. The close coupled overfire air compartments are supported at a first elevation in the furnace and the separated overfire air compartments are supported at a second elevation in the furnace so as to be spaced from but aligned with the close coupled overfire air compartments.

Abstract: Grid strips for a nuclear fuel assembly grid have elongated weld tabs. The weld tabs are bent against the strips along the intersection with an adjacent orthogonal strip. The tabs are dimensioned and positioned to initially extend substantially the entire length of the intersection of two grid strips. The tabs are then melted during the welding process.

Abstract: The laser beam welding of a spacer grid assembly is accomplished by dividing a laser beam (21) into at least two beam segments (37). These beam segments (37) are then routed around the mixing vanes (31) and focused below the vanes (31). The focus and coincidence (34) of the beam segments (37) may be moved down along the intersection to provide an elongated smaller diameter weld. The spacer grid assembly of the present invention has an improved Departure from Nucleate Boiling performance, increased strength against buckling, and a reduced detrimental effect on the coolant flow.

Abstract: A removable and reusable cap for fuel rod ends to prevent grid damage during loading permits fuel end configurations to match utility's special tooling for fuel assembly repair and reconstitution. The elastomeric transitory fuel rod guidance ends expand over a flange and temporarily snap into place in a groove in the fuel rod end to provide a tapered guiding surface.

Abstract: A watertight cover for the hook, hook block and cables of a crane comprises a hook box, of a size to receive the hook, fixed to a first cover member, which is of a size to receive the hook block. A second cover member is telescopically carried on the first cover member. Remotely controlled means are provided for displacing the second cover, relative to the first cover, as the hook is lowered into the water.

Abstract: A wear resistant coating (50) for fuel rod cladding (20) comprises a ceramic material (52) which is premixed with a glass (54). The cladding tube is heated and the ceramic/glass mixture is flame sprayed onto the cladding tube. The coating is applied to lower portions of the fuel rods (10) in the area of the first support grid (12) where debris tends to fret the fuel rod.

Abstract: A method for detecting changes in the rate of heat transfer through a tube wall due to the deposition or removal of deposits formed thereon. The method involves obtaining a segment of tubing, placing a highly conductive material in contact with one of the inner surface and outer surface of the tubing wall, contacting the other of the inner and outer surface of the tubing wall with a heating or cooling medium, and measuring the time required for the temperature of the thermally conductive material to change between two predetermined temperature measurement points. Subsequently, the wall of the tubing segment is cleaned or the tubing segment is replaced with a different tubing segment, and the rate of temperature change of the tube walls is tested again in a similar manner. By comparing the times measured in the first and second trials, the difference in the rate of heat transfer before and after cleaning of the tubing segment can be determined.

Abstract: A method of remotely installing or removing and assembling and disassembling nozzle dams (10) from outside a steam generator manway (14) using a tool set. The tools are a bifurcated segment lifting (torquing and push-pull) tool 60 to unweight and faciltate the operation of sliding dam segments (30,32) edgewise along sliding brackets (40) and bars (44) in an assembly and disassembly operation; a cam-lock component (36) operating T-shaped tool (80) with a nozzle dam rib avoiding offset (88), transverse quick-connect body (50b) straddling tool (90) pull a sleeve (50c) in order to disassembly quick-connects; and, a gasket installing, tensioning and removing hook tool (102).

Abstract: A coupler body 12 with a socket 44 therein is attached to nuclear stream generator tools to be mated with an arm 22 of a remotely controlled manipulator. A plug 16 for insertion in socket 44 is mounted with a ball detent lock actuating air cylinder 18 on L-shaped bracket 20 attached to the end of arm 22. Cam surfaces 62 on body 12 and 64 on bracket 20 align the plug 16 and socket 44 for insertion to mate and couple the tools and arm 22.

Abstract: An apparatus for measuring an outside diameter of a cylindrical object moving along an axis includes a plurality of fixed transducer pairs for providing a continuous outside diameter profile of the moving cylindrical object. The sensors are located in a holder enveloping the cylindrical object. Temperature compensation for changes in temperature in the coupling medium include a wire reflector in an ultrasonic path at a fixed distance from a face of the sensor. Various types of outputs, including a continuous profile of the cylindrical object are provided. A method of measuring the outside diameter of such cylindrical objects while moving is also disclosed.

Abstract: Bottom end fuel assembly reconstitution is permitted by elimination of weld of Inconel lower grid perimeter strip to stainless steel lower end fitting. Slots in 2 or 3 sides of L.E. Fitting capture ribbed sections of grid perimeter strip, locking screws hold L.E. Fitting in position on guide thimbles. Grids lip on perimeter strip is interlocked by sliding in L.E. Fitting groove.

Abstract: A tool for axially removing a defect-containing length portion from a steam generator tubesheet primary side grips the tube length portion on both sides of the defect by radially outwardly moving gripper structure in the form of expanding ferrules (16,20) or collet spring fingers (60). Structure in the form of a central mandrel member (12, 13 or 50, 52, 54) moves axially to actuate the gripper structure. A sleeve (62) separately actuated on the mandrel (50) assists this action in the collet spring finger (60) embodiment. Movement of the defect-containing length portion requires an initial cutting of the tube-to-tubesheet weld, and for convenience, separation of the tube length portion from the remainder of the tube. Hydraulic structure (32, 56, 64) provides the motion axially of the grippers' actuators (14, 22, 23 or 58, 66) on either side of the defect either independently or together.

Abstract: A strip (16) for an eggcrate-type nuclear fuel assembly grid (10), in which the fuel rod support springs (30,36) are formed by beams (75,77) and a connecting arch (78). More particularly, the strip has a substantially flat body (56), upper and lower edges (84,86) defining the strip vertical height, and opposed side edges (80) defining the length of the body. The fuel rod support structure (30) projects transversely from the body and comprises a plurality of spring members spaced apart in the longitudinal direction along the body, each spring member having a pedestal portion (75,77) resiliently supported by the body and a contact portion (78) integrally formed on and projecting from the pedestal portion. The pedestal portion preferably includes a beam integrally constrained at both ends by the body. By integrally fixing the ends, the spring member can be considerably smaller and produce the same force for a given deflection as a conventional grid.

Abstract: A watertight cover for the hook of a crane comprises a cylindrical rod interposed between the hook and the load. A circular seal, slidingly carried on the rod, engages an imperforate cover member telescoped over the rod and the hook. A device is provided for drawing the seal and cover member toward the hook as the hook is lowered into the water.

Abstract: An improved lower end fitting (L.E.F.) having a bell mouth type of flow jet diffuser decrease pressure drop 10-15%, more evenly distributes flow and adds strength. It includes neutron thimble flux impingement shield of instrument and/or cable. Diffusers are stainless steel of circular cross-sect. and parabolic to optimize diffusion. Shape is based on lower core plate flow hole geometry, L.E.F. design and reactor flow rate. Thinner L.E.F. legs, smaller L.E.F. gussets and thinner L.E.F. flow plates possible.

Abstract: A device for aligning nuclear fuel pellets, for insertion into fuel rods, comprises a vibrating table and a conveyor assembly adapted to receive pellets poured from a container and to deposit them in a single layer on the table. The upper surface of the table is formed with a number of parallel, substantially v-shaped grooves in which the pellets become aligned. The conveyor assembly, which comprises a horizontal traveling belt and an inclined planar slide, is slid along above the table to facilitate the distribution of pellets thereon. An inspection station, adjacent the table, comprises a number of rotating, parallel rollers in columnar-flow communication with the table grooves. Aligned pellets from the table are delivered onto the rollers where they slowly rotate, presenting their circumferential surfaces for visual inspection. A displaceable control member, transversely disposed between the table and the inspection station, controls transfer of pellets therebetween.

Abstract: A method and apparatus for assembling an egg-crate type grid (10) by orthogonally interengaging slots (30,32) cut transversely into one longitudinal edge of each of a plurality of metal strips (12,14). A first plurality of strips (14) is supported on their lower unslotted edges in north-south orientation so that the strips are uniformly spaced apart in parallel in the east-west direction with all the slots (32) oriented upwardly on the upper edge. The slotted upper edges (26) of adjacent north-south strips are then spread farther apart in the east west direction while maintaining the lower edges (28) at said uniform spacing. The lower, slotted edges (24) of a second plurality of east-west oriented strips are interengaged with the north-south strips while the selected portions of the upper edges of the north-south strips are spread. The upper edges of the first plurality of strips are then returned to the unspread orientation.

Abstract: A nuclear steam generator 10 with economizer 32 adjacent secondary side feedwater inlets 38a and 38b includes a secondary side divider plate 36 and handholes 40 at opposing 180.degree. locations in alignment with the ends of the plate 36. Notches 42 in the ends of the plate 36 adjacent the aligned handholes 40 facilitate inspection and maintenance access on the secondary side above tubesheet 22. To prevent bypass flow from one side of the divider plate 36 to the other, a novel flow blocker 50 of cylindrical shape is provided for mounting in handholes 40 and notches 42. The flow blocker 50 is defined by telescopically assembled member 52 and 62 which are biased in opposite directions by pre-loaded spring 64 therein to insure stability against vibration and flow induced loads. The flow blocker 50 fits sungly in notch 42 and handhole 40 and is bolted to the inside of closure plate 74 of handhole 40.

Abstract: A permanent pool seal and neutron shield 30 for providing an effective water barrier over the annular space 28 between a nuclear reactor vessel flange 24 and a surrounding annular ledge 22 includes annular deck sections 32 supported on spaced ribs 46.Flexible membranes 50,52 on the deck section peripheries accommodate relative movement. Openings 42, each with a removable plug structure which includes cover 44 and tapered can 60, provide vessel cavity 14 with ventilation and maintenance access. All cans 60 and similar containers 56 and 59 under the deck structure and flange 24 contain a shielding material 58 in the form of a boron-containing concrete. Supported below the cans is refractory insulating material 54.

Abstract: An integrated manufacturing system operative for managing the distribution to a factory floor as well as throughout a factory of the information that is necessary to effectuate the production of products on the factory floor. The information required for this purpose encompasses, but is not necessarily limited to, both the design information which is generated within the engineering enterprise and the scheduling information which is generated within the manufacturing resource planning system. This information consisting of design and manufacturing data pertaining to the product to be produced is in turn stored in a central repository for all shared information from whence as needed it is capable of being distributed in a logical and efficient fashion through operation of the integrated manufacturing system to the factory floor as well as throughout the factory so as to thereby enable the product to be produced on the factory floor in a most timely and most cost-effective manner.