Cask System Design Guidance for Robotic Handling

Remote automated cask handling has the potential to reduce both the occupational exposure and the time required to process a nuclear waste transport cask at a handling facility. The ongoing Advanced Handling Technologies Project (AHTP) at Sandia National Laboratories is described. AHTP was initiated to explore the use of advanced robotic systems to perform cask handling operations at handling facilities for radioactive waste, and to provide guidance to cask designers regarding the impact of robotic handling on cask design. The proof-of-concept robotic systems developed in AHTP are intended to extrapolate from currently available commercial systems to the systems that will be available by the time that a repository would be open for operation. The project investigates those cask handling operations that would be performed at a nuclear waste repository facility during cask receiving and handling. The ongoing AHTP indicates that design guidance, rather than design specification, is appropriate, since the requirements for robotic handling do not place severe restrictions on cask design but rather focus on attention to detail and design for limited dexterity. The cask system design features that facilitate robotic handling operations are discussed, and results obtained from AHTP design and operation experience are summarized. The application of these design considerations is illustrated by discussion of the robot systems and their operation on cask feature mock-ups used in the AHTP project. 11 refs., 11 figs

LSQFT: a nonlinear least squares data fitting subroutine suitable for minicomputers. [In FORTRAN for Hewlett Packard 1000]

The FORTRAN subroutine LSQFT is described which uses the Gauss method to fit nonlinear functions to data. This particular program is suitable for use on a minicomputer that is utilized for real-time data acquisition and analysis. A sample problem is described that requires a nine-parameter nonlinear fit to 200 data points. This problem serves both to illustrate the use of LSQFT and to compare its results with TJMAR1, a nonlinear parameter estimation program available in the Sandia MATHLIB, for the CDC 6600/7600 computers. The results of this comparison fit are identical to the significance of the input convergence criteria. The output of LSQFT includes the standard deviation of each fit parameter, which is useful for analysis of the significance of the parameters based on the input data or for evaluation of functional models used to fit to the data. Examples are given of the types of graphical output that can be generated from the results of LSQFT. The program is documented and listed in its entirety, and a user's guide is provided. 10 figures

Thermal expansion and density measurements of molten and solid materials at high temperatures by the gamma attenuation technique

An apparatus is described for the measurement of the density and thermal expansion of molten materials to 3200/sup 0/K using the gamma attenuation technique. The precision of the experimental technique was analytically examined for both absolute and relative density determinations. Three analytical expressions used to reduce data for liquid density determinations were evaluated for their precision. Each allows use of a different set of input data parameters, which can be chosen based on experimental considerations. Using experimentally reasonable values for the precision of the parameters yields a similar resultant density precision from the three methods, on the order of 0.2%. The analytical method for measurements of the linear thermal expansion of solids by the gamma method is also described. To demonstrate the use of the technique on reasonably well-characterized systems, data are presented for (1) the density and thermal expansion of molten tin, lead, and aluminum to 1300/sup 0/K, (2) the thermal expansion of solid aluminum to the melting point, and (3) the thermal expansion of a low melting point glass through the transition temperature and melting region. The data agree very well with published results using other methods where such published data exist

Design of a high precision dilatometer using laser interferometry

This study examines the design of a high precision dilatometer which utilizes laser interferometry as the basis for the length measurement system. The dilatometer is being designed for operation from ambient to 800/sup 0/C using samples which require minimal preparation. Several interferometric techniques useful to dilatometry were reviewed from the literature. As a result of this review and establishment of performance criteria, a technical design is proposed. The optical design incorporates a two-frequency He--Ne laser with ac detection in a modified Michelson interferometer. A vertical sample/furnace configuration appears to offer a number of design advantages. Operational considerations and dilatometer development costs are also presented

Automated waste canister docking and emplacement using a sensor-based intelligent controller; Yucca Mountain Site Characterization Project

A sensor-based intelligent control system is described that utilizes a multiple degree-of-freedom robotic system for the automated remote manipulation and precision docking of large payloads such as waste canisters. Computer vision and ultrasonic proximity sensing are used to control the automated precision docking of a large object with a passive target cavity. Real-time sensor processing and model-based analysis are used to control payload position to a precision of {plus_minus} 0.5 millimeter

Thermal expansion of molten uranium dioxide

The density and thermal expansion of molten UO/sub 2/ were measured from 3120 to 3250/sup 0/K using the gamma attenuation technique. The density-temperature relation for molten UO/sub 2/ was found to be rho(T) = (8.86 +- 0.06) - (9.16 +- 0.43) x 10/sup -4/ x (T - 3120/sup 0/K) for rho in g/cm/sup 3/ and T in /sup 0/K. The results agreed within experimental error with the single previous measurement. However, the value of the first derivative of density in the molten phase with respect to temperature was found to be approximately 50% higher than the value recommended in a review of properties for reactor safety analysis. 4 figures

Thermal conductivity of aqueous foam

Thermal conductivity plays an important part in the response of aqueous foams used as geothermal drilling fluids. The thermal conductivity of these foams was measured at ambient conditions using the thermal conductivity probe technique. Foam densities studied were from 0.03 to 0.2 g/cm/sup 3/, corresponding to liquid volume fractions of the same magnitude. Microscopy of the foams indicated bubble sizes in the range 50 to 300 ..mu..m for nitrogen foams, and 30 to 150 ..mu..m for helium foams. Bubble shapes were observed to be polyhedral at low foam densities and spherical at the higher densities. The measured conductivity values ranged from 0.05 to 0.12 W/m-K for the foams studied. The predicted behavior in foam conductivity caused by a change in the conductivity of the discontinuous gas phase was observed using nitrogen or helium gas in the foams. Analysis of the probe response data required an interpretation using the full intergral solution to the heat conduction equation, since the thermal capacity of the foam was small relative to the thermal mass of the probe. The measurements of the thermal conductivity of the foams were influenced by experimental effects such as the probe input power, foam drainage, and the orientation of the probe and test cell. For nitrogen foams, the thermal conductivity vs liquid volume fraction was observed to fall between predictions based on the parallel ordering and Russell models for thermal conduction in heterogeneous materials