Abstract: A hydrogen reference electrode is disclosed which is applicable to measuring systems for determining the oxygen content in high temperature water in the range of 400.degree. F. to the critical point of water of approximately 713.degree. F. at which it co-exists in the liquid and vapor states and which water is treated to provide a reducing atmosphere. The reference electrode is formed as a closed end tube of palladium-Silver alloy material pressurized with hydrogen gas and enclosed in a perforated sleeve which allows water to be trapped in the space between the alloy tube and the sleeve where the water is saturated with hydrogen permeating through the wall of the alloy tube.

Abstract: A safety system (10) for shutting down a nuclear reactor under overload conditions is provided using a series of parallel-connected computer memory type look-up tables (14a, 14b, 14c, 14d, 14e) each of which receives data on a particular reactor parameter (P, T, .phi..sub.T, .phi..sub.B, W) and each of which has stored therein a precalculated functional value [f(P); f(T); F(.phi..sub.T); f(.phi..sub.B); f(W)] for that parameter indicative of the percentage of maximum reactor load that the parameter contributes. The various functional values [f(P); f(T); f(.phi..sub.T); f(.phi..sub.B); f(W)] corresponding to the actual measured parameters are added together to provide a control signal (S) used to shut down the reactor under overload conditions.

Abstract: A once-through solar steam generator assembly (16) is controlled by a control system wherein the outlet temperature of superheated steam from two independent boiler flow paths (1-12; 1'-12') is independently controlled to a common set point by a combination of water spray attemperation (32) at the primary superheater outlet (34, 36; 34', 36') of each flow path (1-12; 1'-12') and the control of feedwater flow through the independent flow paths (1-12; 1'-12').

Abstract: A broaching tool is manufactured directly from a heat hardened blank of preformed metal by having a grinding wheel of CBN (cubic boron nitride) material cut a broach tooth from the hardened blank by cutting gullets in the blank. The blank is made movable and rotatable relative to the CBN grinding wheel to allow the manufacture of a series of broach teeth forming a broaching tool with various tooth spacings, depths, and angles with respect to the face of the broaching tool.

Abstract: A drag ball valve (10) that can variable regulate the pressure drop to which the fluid passing therethrough is subjected while maintaining the fluid velocity nearly constant is disclosed. To accomplish this, a series of fixed disks (34) having apertures (36) therein and rotatable disks (42) having apertures (44) with flange-like projections (46) therein are aligned so that either an unobstructed straight fluid passage through the apertures in both types of disks is created or the fluid is diverted by the flange-like projections (46) causing pressure reductions due to a variable number of flow direction turns. By varying the number of fixed disks (34) and rotatable disks (42) used, and by varying the number of rotatable disks (42) that are so aligned, any number of flow direction turns and associated pressure drops from zero pressure drops to the total number of rotatable disks (42) used can be achieved.

Abstract: A voltage linearization circuit for use with a resistance thermometer device or a thermocouple to produce a nearly linear output signal from a non-linear input signal. The circuit produces a voltage proportional to the square of the input voltage through the use of operational amplifiers and field-effect transistors connected in voltage dividing arrangements, and combines this second order voltage, or a reduced magnitude thereof, with the original input voltage to produce a nearly linear output signal.

Abstract: A measuring system (10) for measuring the flow of solids (w.sub.s) in a fluid stream is disclosed which utilizes only two differential pressure measurements (.DELTA.p.sub.1 ; .DELTA.p.sub.2) indicating the pressure drop across different points of a venturi (12). The fluid having the solids entrained therein is passed through the venturi (12) and pressure drop measurements are taken at points of the venturi (12). These pressure drop measuurements (.DELTA.p.sub.1 ; .DELTA.p.sub.2) are transmitted to a microprocessor (15) which calculates these measurements (.DELTA.p.sub.1 ; .DELTA.p.sub.2) according to a predetermined empirical formula to yield an output signal indicative of the flow of solids (w.sub.s) through the venturi (12).

Abstract: A method of etching a silicon diffused resistance pressure transducer assembly (13) of a transducer (10) mounted on a glass base (14) providing a thin flexible area on the transducer in the region of the diffused resistors (15) and a thick rigid area in the region where the transducer is mounted to the glass base (14). To accomplish this, the transducer (10) is first bonded to the glass base (14) which is tubular, thus providing a circular area on the backside (16) of the transducer (10) open to ambient. This open area is then filled with an isotropic etchant which etches silicon material but which has little effect on glass material. Thus, the region of the diffused resistors (15) is etched out to provide a thin flexible area while leaving a thick area where the transducer (10) is mounted to the glass base (14).

Abstract: A differential thermocouple hydrogen gas detector (10) is provided by coating one thermocouple junction (34) of a differential thermocouple pair (34, 36) with a Palladium-Silver alloy catalyst (46) and the other thermocouple junction (36) with a non-catalyst (52). Heated hydrogen gas reacts with the catalyst (46) to liberate heat to the catalyst coated thermocouple junction (34) in proportion to the concentration of hydrogen gas and proportionally raise the temperature of the catalyst coated junction (34) above that of the non-catalyst coated junction (36). The output signal (44) from the differential thermocouple device (34, 36) thus provides an output signal indicative of the concentration of hydrogen gas.

Abstract: A pneumatic-hydraulic proportional valve actuator system is provided having a relatively simple and adjustable means of achieving two stroking speeds by the hydraulic actuator, high speed in normal operation and low speed for small position adjustments and for the final part of any large position adjustments. This prevents overshoot and instability of the actuator.

Abstract: A highly flexible spacer-sealer for reflective insulation inner assemblies is provided which spaces a pair of flexible reflective insulation sheets or liners while also sealing a volume of space therebetween. To accomplish this a corrugated strip of material is mounted on its edge between the pair of flexible reflective insulation liners all along the perimeter of the two sheets. The corrugated strip is compressed and twisted at predetermined points and mounted to one of the liners leaving the other liner to lie on the corrugated strip. This construction allows the inner assemblies to be curved and bent to conform to the various shapes of the inner and outer case assemblies which are mounted to the body to be insulated.

Abstract: A broach pulling mechanism is provided utilizing puller jaws which engage with a significantly larger circumferential groove at the end of the broach to pull the broach through a workpiece without any vertical drop of the broach in the puller mechanism during any part of the broaching operation. To accomplish this a piston assembly is mounted at the bottom of the broach pulling mechanism to allow the end of the broach to bottom thereon. The piston assembly is controllably pressurized to lock a wall of the groove of the broach end between the puller jaws and the piston assembly thereby preventing any movement or dropping of the broach due to a loose fit of the jaws with respect to the groove throughout the entire broaching operation.

Abstract: This invention is directed toward a nuclear fuel assembly guide tube arrangement which restrains spacer grid movement due to coolant flow and which offers secondary means for supporting a fuel assembly during handling and transfer operations.

Abstract: An illustrative embodiment of the invention discloses a technique for disassembling a nuclear reactor fuel element without destroying the individual fuel pins and other structural components from which the element is assembled. A traveling bridge and trolley that span a water-filled spent fuel storage pool support a strongback. The strongback is under water and provides a working surface on which the spent fuel element is placed for inspection and for the manipulation that is associated with disassembly and assembly. To remove, in a non-destructive manner, the grids that hold the fuel pins in the proper relative positions within the element, bars are inserted through apertures in the grids with the aid of special tools. These bars are rotated to flex the adjacent grid walls and, in this way relax the physical engagement between protruding portions of the grid walls and the associated fuel pins.

Abstract: This invention relates to an improved system of providing power having a unique generating means of the nuclear reactor variety adapted with a plurality of steam generators in the form of replaceable modular units of the expendable type for the attainment of the optimum in effective and efficient vaporization of fluid during the process of generating power.

Abstract: The invention relates to an alumina based, phosphate bondable, dry refractory mix composition exhibiting an extended shelf life of up to eighteen months and longer. The mixture has the following preferred composition on a weight percentage basis: 40-70% sized tabular alumina, 15-35% calcined alumina, 2-10% hydrated alumina, 1-10% calcium aluminate cement and an acid ingredient such as 3 to 15 weight percent of an 115 percent concentration of polyphosphoric acid. The mix is prepared by a method which comprises the steps of formulating dry ingredients into a mixer, mixing the dry ingredients to a homogenous state, then adding a liquid acid ingredient to the mixture of dry ingredients, and subjecting the dry and acid ingredient mix to a high intensity mixing action for a predetermined period of time. The product is substantially dry to the touch.

Abstract: An ultrasonic search unit for locating defective fuel elements within a fuel assembly used in a water cooled nuclear reactor is presented. The unit is capable of freely traversing the restricted spaces between the fuel elements.

Abstract: A heat exchanger including a pressure vessel and a plurality of heat exchanger tubes extending within the vessel. A tube shroud forms an annular passage between the tubes and the pressure vessel wall. A partition wall, comprising a plurality of openings normally closed by closure means, divides the passage into a fluid inlet compartment and a fluid outlet compartment. In the event the fluid pressure differential between the inlet and outlet compartments attains a predetermined value, at least some of the closure means will open to reduce the pressure differential below the predetermined value. In one embodiment of the invention, the closure means comprise flap valves. In an alternate embodiment of the invention, rupture discs are utilized as closure means.

Abstract: A typical embodiment has an end fitting for a nuclear reactor fuel element that is joined to the control rod guide tubes by means of a nut plate assembly. The nut plate assembly has an array of nuts, each engaging the respective threaded end of the control rod guide tubes. The nuts, moreover, are retained on the plate during handling and before fuel element assembly by means of hollow cylindrical locking cups that are brazed to the plate and loosely circumscribe the individual enclosed nuts. After the nuts are threaded onto the respective guide tube ends, the locking cups are partially deformed to prevent one or more of the nuts from working loose during reactor operation. The locking cups also prevent loose or broken end fitting parts from becoming entrained in the reactor coolant. A tool for selectively locking and unlocking the nuts is presented.

Abstract: An illustrative embodiment of the invention has one or more corrugations formed in the surface of a fuel element grid for a nuclear reactor. Not only does the corrugation enhance the strength of the grid plate in which it is formed, but it also provides a simple and convenient means for regulating the reactor coolant pressure drop through an appropriate choice of the corrugation depth.