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[en] Decommissioning challenges at nuclear facilities around the globe are being addressed by development and deployment of a wide range of tools that are adapted from non-nuclear industries. Robust hose assemblies originally developed for the North American chemical processing industry were qualified for use in decommissioning US nuclear facilities in the period 1999 to 2003 and successfully deployed and operated at several US Department of Energy's sites since then. Similar equipment has recently been selected for service at Areva's La Hague site. These assemblies consist of a primary radioactive waste transfer hose encased within a secondary containment hose. Multiple assemblies can be joined together to form an integrated, double-contained piping system. This arrangement, referred to as a Hose-in-Hose Transfer Line (HIHTL), provides the site operator with a fully qualified piping system that can be rapidly deployed to transfer radioactive waste liquids and slurries from at-risk storage facilities, either in response to emergencies or as a part of planned waste treatment and facility decommissioning activities. Areva NC has organized the 'Projet de Reprise et Conditionnement des Dechets' (RCD Project) to manage waste forms at the La Hague commercial nuclear fuel reprocessing site. La Hague's Silo 130 waste storage facility is located in the northwest corner of the site. Tanks 43 and 44 in the Silo 130 facility store a mixed solution of water, powdered graphite, corrosion products, Mg+ and U. Combined, these two tanks hold a total of about 1500 m3 of this waste in interim storage. Future treatment plans include transferring the waste currently stored at Silo 130 to the site's liquid waste treatment facility STE3, located about 1.3 km away. Treatment of the waste now stored in Silo 130 is not planned to occur for several years. As a result of a decision by the French regulator ASN, one near-term task of the RCD Project is to prepare an emergency liquid waste transfer capability that can be rapidly deployed and relied on to empty the liquid contents of these tanks, in the event leakage is detected during interim storage. There is no existing piping system to support transfer of Silo 130 waste to the STE3 treatment facility. Early concepts of how to rapidly empty Tanks 43 and 44 drew from the LR-56 radioactive waste transporter model, and considered a process of loading/transport/off-loading of liquid waste using tanker trucks. As the concept was refined, it became apparent that this approach could be deployed to the field and start emptying the liquid contents of the Silo 130 tanks quickly. However, the total number of tanker loads to complete the mission using this approach could result in a total time to empty the liquid contents of the tanks of several months. Following engineering studies and workshops held with Areva Federal Services, LLC (AFS) of Richland, WA, USA, the RCD Project decided to rely on HIHTL technology as the piping system for this emergency waste transfer capability.
[en] In order to develop heavy gauge WPHY-80 pipe fitting steel with high strength and low temperature toughness, the experimental research and manufacturing technology have been studied in this paper. The continuous cooling phase transformation behavior of the material under deforming condition was investigated. The microstructure of the steel at different cooling rates was observed by microscope. The temperature gradient rolling process in rough rolling stage was developed, which prompt the deformation penetrated from the surface to the center. It could refine the grain size in the center of the thick plate to enhance uniformity of the microstructure along the thickness direction. By utilizing this process route, the heavy gauge (54mm) WPHY-80 pipe fitting steel with excellent mechanical properties was developed in Shougang steel (SG). The WPHY-80 plates obtained high strength and stable low temperature impact toughness. (paper)