Filtered generated 403 hits.
-
2017:25 Evaluation of weld fatigue reduction in austenitic stainless steel pipe components
Background The performed investigation is a continuation of the work performed in SSM 2015:38 where fatigue tests were performed on pressurized welded austenitic stainless steel piping components. The specimens were subjected to a realistic variable amplitude loading with mainly reversed bending deformation and particular focus on high cycle fatigue. The previous fatigue results were quite...
Content type: Publications -
2017:11 Extended Common Load Model: A tool for dependent failure modelling in highly redundant structures
Background The treatment of dependent failures is one of the most controversial subjects in reliability and risk analyses. The difficulties are specially underlined in the case of highly redundant systems, when the number of redundant components or trains exceeds four. The Common Load Model (CLM), originally defined in the 70’ies, differs from other CCF models, as it relies on a specific...
Content type: Publications -
2022:18 Data report – sampling of sea water and marine organisms outside Ringhals NPP
SSM perspective Background The Radiation Safety Authority (SSM) funded the collection of marine biota over an annual cycle at the Ringhals nuclear power plant (NPP) to enable development of analytical methods for C-14. Methods for the C-14 analysis and results in the form of levels of C-14 in various marine organisms have been reported by the Swedish Defense Research Institute (FOI) in FOI...
Content type: Publications -
2021:04 Calibration of models for cladding tube high-temperature creep and rupture in the FRAPTRAN-QT-1.5 program
SSM perspective Background In Swedish Light Water Reactors (LWR), stress corrosion cracking of reactor components and welds occurs from time to time. As the nuclear power plants are ageing, it is essential to study and further understand the mechanism for environmentally induced sensitization. Natural cracking is a phenomenon that is difficult to predict and very hard to study since it occurs...
Content type: Publications -
2021:10 Establishment and use of attention values in environmental fatigue assessments
SSM perspective Background As Swedish NPPs reach their original technical design life, re-assessment of the fatigue life of structural components is needed for safe long term operation (LTO). In these re-assessments one must consider that new knowledge has shown that environmental effects on fatigue life must be considered. One common method to verify the fatigue life of structural components...
Content type: Publications -
2021:20 Effects of additives on UO2 fuel behavior: expanded edition
SSM perspective Background The Swedish Radiation Safety Authority (SSM) follows the development of nuclear fuel closely. Fuel with additives like chromia and gadolinia is used in Swedish reactors and fuel with even better thermal and mechanical properties is under development. This project is an in-depth study of data and models regarding the impact of additives on the properties of uranium...
Content type: Publications -
2021:09 Mechanisms important for material modelling in weld residual stress analysis
SSM perspective Background The prediction of weld residual stresses (WRS) is very complex as many mechanisms and phenomena influence the development of WRS during welding. For accurate prediction, the constitutive material models used are essential and must be able to describe the material response of the weldment constituents. For example, selection of a material model should only depend on...
Content type: Publications -
2023:11 Study of degradation of spent fuel’s structural material and core components under long-term wet storage
SSM perspective Background Sweden is managing the spent nuclear fuel and core components from its commercial nuclear reactors with a national strategic plan. The fuel and core components are initially stored at the reactor site. After an on-site storage period to comply with transportation limits on decay heat and radiation, these materials are shipped to the Clab (Central Interim Storage...
Content type: Publications -
2023:14 Effect of gamma-irradiation on the redox states of the structural iron in bentonite clay
SSM perspective Background Bentonite clay is used as buffer and backfill material which form engineered barrier in the spent fuel repository. The buffer material surrounding the copper canister will be exposed to gamma and neutron radiations, especially during the first few hundred years after closure of the repository. The redox states of the structural iron in montmorillonite, the dominant...
Content type: Publications -
2017:34 Human capability to cope with unexpected events är publicerad
Background In the light of the Fukushima accident, it stood clear that the challenge of the unexpected is of great importance to both regulators and licensees. For SSM, as for many other national regulators, there was a selfevident need to learn more about the capabilities and actions of people when the unexpected arises and conditions are potentially extreme. A task group was set up within...
Content type: Publications