Abstract: The steam generator includes means for limiting the heat absorption of the economizer 28 during start-up and low load operation. An air bypass duct 54 is located to convey air from cold air duct 46 at a location between forced draft fan 44 and air heater 40 to the gas duct 38. The air is introduced upstream of economizer 28 where it mixes with hot flue gases to reduce the temperature of gas flowing through the economizer. Control dampers 56 are operated to maintain the desired temperature at the economizer outlet 30.

Abstract: A process for recovering nonferrous nickel, copper and cobalt from deep sea nodules to obtain a concentrate rich in the nonferrous metals, a middlings less concentrated in the nonferrous metals and a tailings with a very low concentration of the nonferrous metals. The crushed nodules are mixed with middlings, a carbonaceous reductant and a chlorinating agent which is a mixture of sodium chloride with either calcium carbonate or calcium hydroxide. In a non-oxidizing atmosphere, the mixture is roasted at a temperature about 850.degree. C. and then cooled. The roasted material is finely ground, slurried and magnetically separated into the three fractions.

Abstract: A method for testing the clad integrity of a nuclear fuel rod, comprising the first step of fabricating a sealed fuel rod with a wad of electrically conducting material mounted therein. The material is of a type that undergoes a permanent change in electrical conductivity when exposed to water. The next step is to establish an eddy current signal characteristic of the moisture-free rod. The rod is then loaded into the core as part of a fuel assembly. After the producing power, the assembly is removed for inspection, and an eddy current signal is again obtained from the rod. The eddy current signals are compared to determine whether inleakage of moisture has oxidized or otherwise altered the conductivity of the wad enough to significantly change the characteristic signal.

Abstract: A length-adjustable device is provided for use in applying setting force to a set of pipe slips, e.g. in a petroleum well. Then, the length of the device is adjusted and the device is installed on a seat in the head as a mechanical bridge between the set slips and an axially presented surface on an overlying part of the wellhead. Due to this interposition, the slips are prevented from losing gripping force as the suspended pipe expands and contracts.

Abstract: An automatic voltage control system controls the firing angle of a solid state switch (20), in turn the voltage applied to the primary winding (12) of a step-up transformer (10), in turn the voltage applied to the grid (38) and in turn the electric field intensity between grid elements (38) in an electrostatic separation process. Two voltage control signals are generated in the control system. The first voltage control signal is a protective control signal generated to maximize the voltage applied to the primary winding under normal operating conditions and to reduce the voltage to zero for a short time period following abnormal operating conditions then to reapply voltage to the primary winding (12) again. The second voltage control signal is a periodic signal of adjustable rate and frequency that functions as a variable upper limit to the magnitude of the first control signal.

Abstract: A method and apparatus for removing and replacing the primary manway cover (18) which is secured to the shell (10) of a nuclear steam generator by a multiplicity of nuts (24) and studs (22), including the steps of removing two of the studs and replacing them with two overlength special studs (30); removing the nuts (24) from all of the other studs (22); unthreading the nuts (24) on the overlength studs (30) until the cover (18) is positioned outside the ends (28) of the other studs (22); attaching (44) a cable (40) to the periphery of the cover; removing one of the overlength studs (30); and pivoting the cover (18) on the other of the overlength studs (30) out of alignment with the manway opening while supporting it by means of the cable (40).

Abstract: A wood-burning stoker grate is provided a barrier across its rear end functioning as an impact surface for fuel and foreign matter projected toward the rear of the stoker grate. The barrier is made up of two sections, each section formed of parts with the same configuration as parts used in the stoker grate.

Abstract: A steam generating heat exchanger (2) for cooling a high pressure, hot gas laden with molten ash particles comprising an inverted U-shaped pressure containment structure (4,6,8) having various heat exchange means disposed therein. The heat exchanger is formed of a first vertically elongated cylindrical pressure containment vessel (4) housing a radiant cooling chamber (12) therein, a second vertically elongated cylindrical pressure containment vessel (6) housing a convective cooling chamber (30) therein, and a pressure containment pipe (8) connecting the second pressure containment vessel (6) to the first pressure containment vessel (4) and housing therein a water-cooled duct (26) connecting the gas outlet of the radiant cooling chamber (12) disposed within the first pressure containment vessel (4) to the gas inlet of the convective cooling chamber (30) disposed within the second pressure containment vessel (6).

Abstract: A system receives raw coal which is routed through crushing, screening, pulverizing, classifying, and beneficiation stages with the de-mineralized fraction of the coal routed to a pulverized-coal-fired furnace, while the mineralized fraction is routed to a fluidized bed furnace.

Abstract: A buckstay stirrup for a steam generator is formed from a single plate, requiring only cutting and bending. The plate after cutting is bent to form two angled support portions (24) and a central portion (20). The outboard section (22) of the intermediate portion is cut (32) so that it extends inwardly to engage the inner edge of a buckstay, which is in the form of an I-beam. The central intermediate portion (20) is formed to be located inwardly of the outboard portion and contains an accordian fold (30) to permit the shortening which occurs during the bending. The two intermediate portions (20,22) are in parallel planes spaced to accept the buckstay flange therebetween.

Abstract: An improvement in fluid pressure transducers having a housing with oppositely facing magnetic blocks (12,14) that form a sealed chamber (20) in which a magnetically permeable diaphragm (24) is disposed for magnetic coupling with electromagnetic coils (30) mounted within the blocks. The coil is mounted on an elongated plug (34) and covered by a non-magnetic, unitary metal cap (36) that is flexibly sealed between the chamber and the coil. The cap has a generally cup-like inner portion (48) for covering the coil and a flat rim portion (46) that is sealingly (58) secured between the mounting plug and shoulder means (50,60) within the block.

Abstract: A torque structure particularly suitable for utilization in a power reactor of the Tokamak-type, and operable therein for purposes of providing support for the toroidal field (TF) coils that comprise one of the major operating components of such a Tokamak power reactor. The subject torque structure takes the form of a frame structure that is operable to enable torque loads acting on the TF coils to be equilibrated as close to the area of force application as feasible. The aforesaid torque structure includes an intercoil structure composed of spacer wedges that are interposed between each adjacent pair of TF coils. The spacer wedges, in turn, consist of bearing plates positioned between the TF coils so as to be in contacting relation therewith and a number of cross plates that are cooperatively associated with the bearing plates so as to form therewith a rigid assembly. The intercoil structure is affixed to a segmented, membrane shell that surrounds, encloses and supports the TF coil frames.

Abstract: An improved nuclear fuel assembly in which the lowermost grid is located close to the lower end fitting of the assembly, and a conventional Zircaloy-clad fuel rod is fitted with a stainless steel tip having a bevelled notch thereon for engaging resilient means on the grid within about one inch (2.5 cm) from the lower tip of the fuel rod. The notch mechanically restrains the fuel rod from lifting upwards during reactor operation, yet is shallow enough to permit removal of the fuel rod in the event reconstitution is required. The stainless steel tip is mechanically secured to the Zircaloy end cap of the fuel rod, and is located in a low importance flux region of the core so that the higher neutron poison absorption cross section of stainless steel is of little consequence. Since the lowermost grid secures each fuel rod within one inch of the lower end of the rod, there is little likelihood that the coolant flowing over the lower ends of the fuel rods will induce significant vibrations.

Abstract: A pump for feeding granular material into a pressurized zone having a feed screw (14) located within a cylinder (12). The cylinder is tapered (34) at its discharge end, and the outside diameter of the flights (32) is also tapered (43). The clearance (38) of the tapered flights is significantly greater than the clearance (40) of the non-tapered flights.

Abstract: In order to provide a metal-to-metal annular seal for use in a high pressure environment typical of a wellhead assembly that is provided on a high pressure, high temperature gas well, especially circumferentially between the outside surface of a tubular part and the inside surface of a relatively massive part, where these parts are to have a fixed longitudinal position relative to one another in use: the available strength for developing the seal are determined; like tapering surfaces are provided on the two parts such as would provide an allowable interference fit when the two parts are brought to the fixed longitudinal position; portions of the outside surface of the tubular part are machined-away to leave tapered land areas, e.g. in two axially closely spaced bands, so that when the two parts are forced to assume the fixed longitudinal position, the seal bands provide an elastic seal that avoids total plastic deformation yet provide the required unit loading.

Abstract: Apparatus for supporting screen (12) in a screening machine (10) that will permit long-life of the screen even when subjected to heat and vibration. The screen or wire cloth edge is folded over (30) and fastened or joined (42, 44, 46), with a metal rod (32) inserted down through the foldover space (34). Spring clips (40) or other adjustable tensioning devices attach the steel rod (32) to the screening machine frame (50), thus placing the screen (12) in tension.

Abstract: A method particularly suited for manufacturing a pulverizer, i.e., grinding, roll (18) of the type that is designed to be embodied in a bowl mill (10) so as to be operative therein for purposes of effecting the pulverization of a material such as coal through the coaction of the pulverizer roll (18) with another surface with which the bowl mill (10) is provided for this purpose.

Abstract: A flexible ceramic fiber board is formed from fibers with a homogeneous latex binder coating. The coating is formed from a slurry of the latex, a cationic acrylamide base copolymer and aluminum sulfate solution. The cationic copolymer aids the aluminum sulfate in homogeneously depositing the latex and forming a uniformly flexible board. The shape that is formed is dried dielectrically. The crystalline, high Al.sub.2 O.sub.3 fibers may be mixed with non-crystalline, Al.sub.2 O.sub.3.SiO.sub.2 fibers.

Abstract: A fluidized bed furnace (10) for generating steam (26) is designed to operate over a given load range, for example from 50% of full load to maximum capacity rating (MCR). The air distributor (12) is designed with a constant pressure drop restriction means or "float" (36) in each air inlet (18). As the load varies, the pressure drop across the float (36) will remain constant, reducing the overall fan horse power requirements.

Abstract: Apparatus for handling ash and slag produced in the combustion of coal or other ash-bearing fuel in the furnace (10) (not shown) of a steam generator, including a submerged scraper conveyor (20) beneath the furnace, and a water seal including plate means (24) extending from the furnace bottom or transition chute into the water (18) in the tank (16) housing the scraper conveyor, which plate means (24) also form a seal at their upper ends (40,42) with the furnace bottom or transition chute, for preventing the atmosphere from being exposed to the furnace interior. A motor (50,52) is provided for moving the plate means (24) upwardly and downwardly, to allow the submerged scraper conveyor (20) and its tank (16) to be quickly removed from beneath the furnace (10) when the unit is shut down for maintenance purposes.