Abstract: A combustion subsystem with a circulating fluid bed boiler (12) having a pantleg configuration. The boiler includes front (22) and back (24) walls with external fluid bed heat exchangers (48) integral therewith. In addition to the conventional fuel inlets (54) which provide for entry of fuel into the side walls of the boiler through conduits connected to the seal pots (36) of solids recycle cyclones (30), supplemental fuel inlets (63, 66, 70, 72) are provided on the front and back wails of the boiler through the fluid bed heat exchangers or between adjacent fluid bed heat exchangers. The invention improves combustion efficiency in large boilers by reducing the theoretical mixing length within the boiler.

Abstract: A system for performing laser welding comprises an optical lens for receiving an incoming laser beam and for dividing the laser beam into a number of different beam segments. The top surface is defined by a number of different surfaces for respectively dividing the laser beam into the number of beam segments. The optical lens has a convex bottom surface for focusing and directing the beam segments onto a respective number of welding locations. Preferably, the laser welding system is used to simultaneously perform five welds on an improved spacer grid assembly which has a cylindrical member located at each intersection of the spacer strips. By simultaneously performing the five requisite welds, the welding time is significantly reduced. Also, the welding process is simplified since the system only has to be in one position to perform all of the welds at each intersection.

Abstract: The alloy of the present invention features controlled amounts of tin, nitrogen, and niobium and includes tin (Sn) in a range of greater than 0 to 1.50 wt. %, wherein 0.6 wt. % is typical. The alloy also has iron (Fe) in a range of greater than 0 to 0.24 wt. %, and typically 0.12 wt. %; chromium (Cr) in a range of greater than 0 to 0.15 wt. % and typically 0.10 wt. %; nitrogen (N) in a range of greater than 0 to 2300 ppm; silicon, in a range of greater than 0 up to 100 ppm, and typically 100 ppm; oxygen (O) in a range of greater than 0 and up to 1600 ppm, and typically 1200 ppm; niobium (Nb) in a range of greater than 0 wt. % to 0.5 wt. % and typically 0.45 wt. %; and the balance zirconium.

Abstract: A hexagonal grid is comprised of castled strips which are (a) bent into a zigzag form, and (b) interleaved with one another so that half-height bridge segments, which extend between and are integral with adjacent full-height castle segments, are placed in edge-to-edge contact so that they align with one another. This forms a grid with no double thickness portions. During fabrication the strips are sandwiched between slotted top and bottom plates. These plates are formed with access openings at sites where three segments intersect and through which welding is carried out. Relatively long spring features are only formed in full-height castle segments. The absence of these features in the half-height bridge segments allows the overall height of the grid to be minimized.

Abstract: A high efficiency exhauster which is capable of attaining operating efficiencies of up to 70% when employed in a solid fuel pulverizer firing system that includes a pulverizer which is operative to effect the pulverization therewithin of the solid fuel supplied thereto and a furnace into which the pulverized solid fuel is injected for combustion therewithin. The high efficiency exhauster includes a casing, an inlet ring supported on the casing, a rotor mounted on the casing for rotation therewithin, a multiplicity of blades, each of a preestablished length and width, mounted in spaced relation one to another on the circumference of the rotor so as to extend at a preestablished angle, and an outlet formed in the casing.

Abstract: An economizer apparatus for a fossil fuel fired vapor generation apparatus which includes a housing having an inlet and an outlet and a wall extending generally between the inlet and the outlet to define first and second flow paths in the housing. The inlet may include means for connection to an associated vapor generation apparatus and means for connection to an associated stack. Heat exchange tubing is disposed in the first flow path having the interior thereof coupled to associated working fluid of the vapor generation apparatus. The apparatus also includes apparatus in the second flow path to control flow in the second flow path. In most embodiments of the invention the apparatus also includes a bypass conduit for selectively directing fluid flow around the heat exchange tubing. Ordinarily this will be desirable when the damper is obstructing fluid flow in the second flow channel.

Abstract: A tool system features an EDM crack removal head which can be positioned within a nozzle/thermal sleeve and then oscillated in a vertical and horizontal directions to enable precise material removal, leaving the surface free of cracks and in a condition for rewelding if required. If a crack is found in a surface which is covered by a thermal sleeve, then a small specialized EDM cutting head, which can be delivered from the under side of the reactor head and has an ability to pass through the ID of the thermal sleeve, is used. The head enables the sleeve to be cut and allow a portion of the sleeve to be removed. The crack can then be removed using a crack removal type of head.

Abstract: A furnace apparatus which includes a plurality of water walls each including a plurality of tubes, the water walls collectively enclose a combustion chamber. The apparatus includes a plurality of windboxes and each of the windboxes are disposed intermediate adjacent water walls. A seal assembly seals the interface between respective windboxes with the water walls adjacent thereto and each of seal assemblies comprising first and second generally planar plates disposed in face to face abutting relationship. The apparatus also includes first means for mounting the first plate to the water wall and second means for mounting the second plate to the windbox. The means for mounting the first plate and the means for mounting the second plate define a chamber therebetween, the apparatus also includes means for enclosing the chamber that includes a flexible member allowing relative movement between the first and second plates.

Abstract: Through a localized compact workstation (104), the operator is offered all the monitoring, alarming and control functions which have been previously dispersed over many control panels located throughout the control room (100). The information display hierarchy is composed of an IPSO overview display (122), video display units (108) preferably based on CRT technology and qualified video display units (116) preferably based on solid state flat panel display technology. Associated with each display unit is an individual, independent control module to allow process and component control. One control module (112) supports non-safety control functions and avoids separate controllers for components and process control. Another control module (118) is a qualified system which supports safety system control functions and avoids separate controllers for component and process control.

Abstract: A self-sampling corrosion monitor is structurally adapted to be connected to the blowdown system or other piping systems external to a steam generator. The monitor includes a pump for providing positive solvent flow through the monitor, and a regenerative heat exchanger using recovered heat at the outlet. Magnetite is also added to a sludge cup within the corrosion monitor vessel to simulate real time measurement of short-lived corrosion conditions in the steam generator. In addition, the available corrosion monitoring equipment is modified to provide automatic microprocessor-controlled range selection. Still further, data acquisition, storage, and display techniques are modified.

Abstract: The alarm activation set point and priority for a given, spatially fixed alarm tile can vary depending in part on the mode of plant operation.

Abstract: Indicating the priority of a spatially fixed, activated alarm tile on an alarm tile array by a shape coding at the tile, and preferably using the same shape coding wherever the same alarm condition is indicated elsewhere in the control room. The status of an alarm tile can change automatically or by operator acknowledgement, but tones and/or flashing cues continue to provide status information to the operator.

Abstract: Alarm acknowledgment can be made not only at the alarm tile array of a given console but via other touch sensitive alarm indications in the screen displays of the monitoring system at the same or other consoles; also, touching one tile can acknowledge multiple alarm sources.

Abstract: A metal component (10) having non-uniform material characteristics which cause the component to undergo differential growth upon exposure to a neutron flux, and a process for producing such a component. The invention is useful for making metal components for use in nuclear reactors, particularly fuel assembly cantilever grid springs (12). By cold working a portion (40) of a cantilever spring on the convex side of the curved region of the spring, a spring can be provided which has a smaller reduction in preload upon exposure to radiation than a conventional cantilever spring.

Abstract: By using AVLIS or other methods capable of providing a depleted isotopic mixture, troublesome isotopes such as Gd.sup.154, Gd.sup.156 and Er.sup.166 are selectively removed from naturally occurring isotopic mixtures, while avoiding the additional costs associated with complete fractionation of the mixture. Such mixtures can be used to provide a burnable nuclear fuel absorber having a selectively depleted isotope or isotopes. In particular, the invention concerns burnable absorbers containing erbium with a depleted 166 isotope, gadolinium with a depleted 156 isotope or with depleted 154 and 156 isotopes, and methods for making such absorbers.

Abstract: A damper assembly particularly adapted for use in a hot furnace application that includes a damper blade, a housing having a passageway therein dimensioned and configured for receiving the damper blade, and a shaft carrying the damper for rotational movement in the passageway in the housing. A bearing is disposed at one axial extremity of the shaft. The apparatus also includes bearings including a bearing housing member having an interior portion thereof which is spherical section shaped and a bearing member disposed therein having an outer surface that is a spherical section dimensioned and configured for cooperation with the inner portion of the bearing housing member. The inner members has a bore tightly engaging the shaft and the bore has inboard and outboard ends. The inner member includes a counterbore disposed in concentric relationship with the bore at the inboard end thereof. A seal is disposed in the counterbore intermediate the shaft and the walls of the counterbore.

Abstract: An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually.

Abstract: A circulating fluidized bed combustion process which uses a sorbent to react with sulfur oxides employs a process for fracturing the sorbent particles to expose unreacted sorbent in the core of the particles to increase the sorbent utilization. The particles within the circulating bed are fractured by injecting water either as a liquid or as steam.

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 multi-elevations 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: A polisher is supported on either a frame/arm arrangement or on a vehicle which is guided by track, and is arranged to be energized to polish a predetermined surface of an annular flange or the like, when relative movement is sensed between the polishing element and the surface to be polished. The polishing arrangement can be motor driven so that the polisher can be left to polish the surface in the absence of an operator.