Abstract: Nuclear fuel cladding tube end plug welds are ultrasonically scanned to develop data indicative of weld thickness, weld penetration, and the existence and size of any included feature, such as pores. A computer analyzes the data to determine critical weld characteristics which are then tested against established quality assurance standards to see if the end plug weld is acceptable, all on an automated production line basis.

Abstract: A method for operating a computer to control the manufacture process of zirconium tubes in a pilger mill operation, the computer including an electronic memory and being coupled to the pilger mill to receive, as input, data related to the operation of the mill. The method comprising, in one embodiment, the steps of storing in the computer memory respective test signals, each test signal corresponding to a signal obtained by inspecting a tube manufactured by the mill with a respective, known defective operation condition, inspecting a zirconium tube finished by the manufacture process and generating a signal representative of the physical dimensions and material configuration of the tube, comparing the generated representative signal of the zirconium tube with the stored test signals, alerting an operator if the generated representative signal of the zirconium tube correlates to a stored test signal, and identifying the defective operation condition which corresponds to the correlated stored test signal.

Abstract: Nuclear fuel cladding tube end plug welds are ultrasonically scanned to develop data indicative of weld thickness, weld penetration, and the existence and size of any included feature, such as pores. A computer analyzes the data to determine critical weld characteristics which are then tested against established quality assurance standards to see if the end plug weld is acceptable, all on an automated production line basis.

Abstract: A quality assurance inspection system utilizes a plurality of ultrasonic transducers to probe an elongated tube for both dimensional and structural integrity. The transducers are pulsed in rapid succession, and echo signals are conducted over separate RF channels and through a multiplexor to a lesser number of detector signals channels, each including a discriminator. Inspection windows are opened in these discriminators to permit detection of echo signals and the generation of time mark signals for stopping a plurality of clocks which then register pulse-echo time intervals. These data are computer processed to provide tube dimension and flaw information.

Abstract: The disclosed invention comprises a method for assembling fuel bundles for service in nuclear reactors which minimizes damage to the assembled components of a nature that renders the components susceptible to destructive corrosion in service, and the enhanced product of the improved method. The invention includes the utilization of a temporary protective barrier, such as water soluble sodium silicate or gelatin, intermediate the components during assembly.

Abstract: To measure the dimensional characteristics of elongated flow channels for nuclear fuel rod assemblies at the manufacturing site, an upender is utilized to swing a flow channel from a horizontal loading orientation to an upright pre-measurement position and then to shift the flow channel laterally into a measurement position where it is engaged and held by reciprocatingly mounted upper and lower endplugs while its dimensional characteristics are acquired by a measurement carrige mounted for vertical scanning movement along the entire flow channel length.

Abstract: Pellet trays bearing rows of fuel pellets of known enrichment concentrations are retrieved from selected storage elevators and successively conveyed to a zone makeup machine. Parallel rows of pellets are raked from each tray and advanced over a longitudinally elongated, grooved loading surface into abutment with a selectively longitudinally positioned stop. A zone makeup carriage makes up the pellet rows to a prescribed, common zone length, which are then weighted and advanced in parallel by a vibratory loader into a plurality of cladding tubes arranged in parallel loading positions by tube handling apparatus. Overall operation is coordinated by a system controller to concurrently load the cladding tubes with multiple pellet zones of varying enrichments and lengths in automated fashion.

Abstract: In the automated production line manufacture of nuclear fuel bundle spacers, rod-supporting ferrules are cut from tubular stock, checked for length, laser cut to create predetermined features in the ferrule sidewall, formed with rod-centering stops in the ferrule sidewall, and checked for stop height dimensional accuracy. Pairs of ferrules are subassembled with a captive spring and assembled into a spacer assembly fixture together with other spacer parts. The fixtured spacer parts are conjoined by laser welding to create a structurally rigid spacer. The various production line operating stations are served by separate controllers linked to a central computer for production status reporting, parts traceability, and overall control purposes.

Abstract: In an automated first weld apparatus, a transporter conveys nuclear fuel cladding tubes successively to a welding station where a separate end plug is welded to an open end of each tube. Thereafter, the transporter indexes the tubes successsively through a cooldown station where the weld is cooled, to a reader station where a unique end plug serial number is read, and then to a succession of inspection stations where the internal and external weld characteristics are automatically examined. The resulting inspection data is correlated with the associated serial number for record purposes and tested against quality assurance standards pursuant to sorting the tubes into accepted and rejected lots.

Abstract: A system for determining the radioactive materials content of the ash or residue from an incinerator of contaminated materials contained in cans. The system includes can handling apparatus, a neutron source for activating the material and neutron and gamma ray detectors for detecting emissions from the materials by which fissile/fertile material content is determined.

Abstract: A system for determining the U-235 and U-238 content in a box of radioactive waste material. The system utilizes a passive arrangement which detects spontaneous gamma ray emission from the material in combination with an active arrangement including a neutron source for activating the material.

Abstract: Radiation detectors measuring gamma radiation from radioactive accumulations in an incinerator through low density refractory windows therein for burning combustible, contaminated wastes from nuclear fuel manufacturing activities.

Abstract: Transport apparatus is disclosed for moving a stream of objects along a substantially continuous path between a source and a collection station and past a viewing station. A stream of successive, spatially separated objects is moved into end-to-end abutment to form successive stacks of objects. Each stack is spiraled past the viewing station with minimal vibration to expose the complete surface of each object to inspection. Subsequently each stack is rearranged into spatially separated objects which are rapidly sorted by diverting those objects from the continuous path which do not conform to predetermined criteria upon inspection. The transport apparatus achieves high throughput without compromising the accuracy of the inspection process.

Abstract: A method and apparatus for determining the subcriticality of masses of uranium by directing epithermal neutrons toward said mass, isolating said material from external thermal neutrons, and measuring the ratio of thermal and epithermal neutrons to epithermal neutrons which enables the establishment of a subcriticality value representative of the mass of uranium.

Abstract: An automated inspection station comprises a pair of rotating rollers for supporting a collected group of pellets. A pusher drops in behind the group to urge the entire group forward. The rotating rollers cause the entire group of pellets to spin in unison as the pellets pass through an optical inspection station. The optical inspection station comprises a light source, diverging and collimating lenses to illuminate each rotating pellet in turn. Signals are generated by at least two arrays of photodiodes in response to light reflected from the surface of the pellets. Circuitry normalizes the signals of the respective diodes for variations unrelated to pellet surface features. The signals are analyzed to ascertain conformance of each pellet to length, cylindricality diameter and surface reflectivity requirements. A pellet sorter diverts unacceptable pellets from the path, while the acceptable pellets are transported to a collection station.

Abstract: Typical nuclear fuel material contains tramp ferromagnetic particles of random size and distribution. Also, selected amounts of paramagnetic or ferromagnetic material can be added at random or at known positions in the fuel material. The fuel material in its nonmagnetic container can be scanned by magnetic susceptibility change detecting apparatus to provide a unique signal waveform of the container of fuel material as a signature thereof. At subsequent times in its life, the container similarly can be scanned to provide subsequent signatures. Comparison of the signatures reveals any alteration or tampering with the fuel material.

Abstract: Method and apparatus for the nondestructive determination of the amount and quantitative distribution of a paramagnetic additive such as gadolinia in nuclear fuel elements. Changes in paramagnetic susceptibility of the material in the element are detected as the element is passed through a constant magnetic field and compared to the changes in susceptibility produced by a standard element of known additive content.

Abstract: The amount of fissile material such as U-235 in each portion of a fuel element, some of which portions may also contain burnable poison such as gadolinium, is determined by detecting the gamma ray emission due to the natural radioactive decay of the fuel material, analyzing the gamma ray signals from each portion to provide a first count of gamma rays primarily due to the U-235 and a second count of gamma rays primarily due to the U-238 daughter products. These first and second counts are corrected for the cladding wall thickness, the density of the fuel material and the burnable poison content in each portion. The first (U-235) count is then corrected by the second (U-238 daughter) count and the thus corrected U-235 count is converted to an indication of the fuel enrichment in each portion. From the enrichment, the burnable poison content, the density of the fuel material and the volumes of each portion, the weight of U-235 in each portion can be determined.