TY - CONF A1 - Auster, Jürgen A1 - Neumeyer, Tino A1 - Müller, Karsten A1 - Droste, Bernhard T1 - Leakage testing during lateral displacement of metallic seals under mechanical accident impact N2 - In context with approval design tests, the IAEA regulations for the safe transport of radioactive material specify tests for demonstrating ability to withstand normal and accident conditions of transport. For 9-m drop test onto an unyielding target the drop orientation of the package must be chosen in a manner so that maximum damage occurs with regard to the safety criteria. With respect to leak tightness after drop test impacts a horizontal or slap-down orientated test model can cause a lateral displacement of the packaging’s lids, affecting the leakage rate of the closure lid system strongly. In Germany dual purpose casks with double lid sealing system composed of primary and secondary lid with bolts, metallic seals as well as cask body sealing surfaces are mainly used. Besides free drop tests with full-scale and half-scale models within licensing approval procedure BAM develops experimental testing methods to simulate defined stresses and deformations by means of components testing. In order to investigate the relation between lateral lid displacement and leakage rate, BAM performs impact tests with small scaled flange-lid systems of transport packages in a drop test machine for guided drop tests. The test setup is realized in a way that the flange part is fixed while a drop weight is impacting onto the lid’s edge. The dynamic displacement of the lid is measured simultaneously. Because of capturing the drop weight after first impact during a short rebound phase by pneumatic arrest mechanism a secondary impact on lid’s edge is excluded. The guided drop tests were accompanied by various measurements such as leakage rate recording during and after impact, identification of lateral shifting by electro-optical displacement transducer as well as decelerations of the lid and the impacting weight. This paper describes the test setup, the test and measurement techniques as well as first results concerning the relation between lateral lid displacement and leaktightness. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 PY - 2013 SP - Paper 168, 1 EP - 6 PB - Omnipress AN - OPUS4-30282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Neumeyer, Tino A1 - Ballheimer, Viktor A1 - Wille, Frank T1 - Investigations of Aged Metal Seals for Transport Package Safety Assessment N2 - Acceptable limits for activity release from transport casks for high-level radioactive material specified in the IAEA regulations must be kept by the integrity of cask body and the cask sealing system. BAM as the German competent authority for mechanical, thermal and containment assessment of packages liable for approval verifies the activity release compliance with the regulatory limits. One of the fundamental aspects in assessment is the specification of conservative package design leakage rates. To ensure the required package tightness for both, storage, and transport of the cask before and after storage usually metal seals of the Helicoflex® Type are used. Due to the long-term use the seal behavior is influenced by temperature and time. The mechanical and thermal loadings associated with the routine, normal and accident conditions of transport specified in the regulations can have a significant effect on the leak tightness of the sealing system. Whereas the safety for application of new, non- aged Helicoflex® seals is verified sufficiently, there are still technical data gaps concerning the efficiency of aged Helicoflex® seals. BAM performed experiments to learn more about the sealing efficiency of aged Helicoflex® seals with Aluminum and Silver outer jackets. The seals were compressed in test-flanges and for artificial ageing the complete flange systems were stored in an oven for several month at a high temperature. During the compression and decompression tests after the aging, load-deformation characteristics of the seals, and leakage rates were measured. With these tests a load situation was simulated, which can occur in the regulatory drop test of the cask: Under high impact loads the bolted lid can lift a little for a short moment, allowing a little movement of the seal, so that the contact area can change before compressing again. The poster presentation will show details about test conditions and first results. T2 - Interdisciplinary research symposium on the safety of nuclear disposal practices safeND2023 CY - Berlin, Germany DA - 13.09.2023 KW - Radioactive material KW - Sealing KW - Ageing KW - Leaktightnes PY - 2023 AN - OPUS4-58436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Neumeyer, Tino A1 - Ballheimer, Viktor A1 - Wille, Frank T1 - Investigations of Aged Metal Seals for Transport Package Safety Assessment N2 - Acceptable limits for activity release from transport casks for high-level radioactive material specified in the IAEA regulations must be kept by the integrity of cask body and the cask sealing system. BAM as the German competent authority for mechanical, thermal and containment assessment of packages liable for approval verifies the activity release compliance with the regulatory limits. The specification of conservative package design leakage rates is one of the most important aspects in assessment. Metal seals of the Helicoflex® Type are usually used to ensure the required package tightness for both, storage, and transport of the cask before and after storage. Due to the long-term use the seal behavior is influenced by temperature and time. The mechanical and thermal loadings associated with the routine, normal and accident conditions of transport specified in the regulations can have a significant effect on the leak tightness of the sealing system. Whereas the safety for application of new, non- aged Helicoflex® seals is verified sufficiently, there are still technical data gaps concerning the efficiency of aged Helicoflex® seals. BAM performed experiments to learn more about the sealing efficiency of aged Helicoflex® seals with Aluminum and Silver outer jackets. The seals were compressed in test-flanges and for artificial ageing the complete flange systems were stored in an oven for several month at a high temperature. After this ageing procedure the flanges were opened completely, the seals were moved a little to vary the contact area, and the flanges were compressed again. During the compression and decompression tests after the aging, load-deformation characteristics of the seals, and leakage rates were measured. With these tests a load situation was simulated, which can occur in the regulatory drop test of the cask: Under high impact loads the bolted lid can lift a little for a short moment, allowing a little movement of the seal, so that the contact area can change before compressing again. Details about test conditions and first results will be presented in the poster. T2 - RAMTrans 2024, 12th Internatiopnal Conference on the Transport , Storage and Disposal of Radioactive Materials CY - London, UK DA - 15.05.2024 KW - Seals KW - Ageing KW - Radioaktiv PY - 2024 AN - OPUS4-60112 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Ballheimer, Viktor A1 - Neumeyer, Tino A1 - Wille, Frank T1 - Application of leakage rates measured on scaled cask or component models to the package containment safety assessment N2 - The containment systems of transport casks for spent fuel and high radioactive waste usually include bolted lids with metallic or elastomeric seals. The mechanical and thermal loadings associated with the routine, normal and accident conditions of transport can have a significant effect on the leak tightness of such containment system. Scaled cask models are often used for providing the required mechanical and thermal tests series. Leak tests have been conducted on those models. It is also common practice to use scaled component tests to investigate the influence of deformations or displacements of the lids and the seals on the standard leakage rate as well as to study the temperature and time depending alteration of the seals. In this paper questions of the transferability of scaled test results to the full size design of the containment system will be discussed. T2 - ASME 2018 Pressure Vessels and Piping Conference CY - Prag, Czech Republic DA - 15.08 2018 KW - Containment KW - Spent fuel KW - Leakage rate PY - 2018 VL - 7 SP - PVP2018-84089, 1 EP - 8 AN - OPUS4-46533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Ballheimer, Viktor A1 - Neumeyer, Tino A1 - Wille, Frank T1 - Application of leakage rates measured on scaled cask or component models to the package containment safety assessment N2 - The mechanical and thermal loadings associated with the routine, normal and accident conditions of transport can have a significant effect on the leak tightness of the containment system of transport casks for spent fuel and high radioactive waste. The containment systems of such transport casks usually include bolted lids with metallic or elastomeric seals. Scaled cask models are often used for providing the required mechanical and thermal tests series. Leak tests have been conducted on those models. It is common practice to use scaled component tests to investigate the influence of deformations or displacements of the lids and the seals on the standard leakage rate as well as to study the temperature and time depending alteration of the seals. In this paper questions and open points of the transferability of scaled test results to the fullscale design of the containment system will be discussed. T2 - 11th International Conference on the Transport, Storage and Disposal of Radioactive Materials CY - London, UK DA - 15. Mai 2018 KW - Transport packages KW - Radioactve KW - Seals KW - Leakage rate PY - 2018 AN - OPUS4-46734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Lars A1 - Scheidemann, Robert A1 - Neumeyer, Tino A1 - Komann, Steffen A1 - Wille, Frank T1 - Tightness Verification Procedures of Welded Lids for Encapsulations for Damaged Spent Nuclear Fuel in the Design Approval Process of Dual-Purpose Cask (DPC) N2 - Damaged spent nuclear fuel (DSNF) can be loaded in Germany in dual-purpose casks (DPC) for transport and interim storage. Therefore, special encapsulations are needed to guarantee a safe handling and a reliable tight closure. These encapsulations must be durable and leak-tight for a possible long interim storage term and the transport thereafter. Because components inside the package containment like these special encapsulations are not accessible within periodical inspections of the DPC. Due to the general design of DPCs for standard fuel assemblies, specific requirements needed to be considered for the design of the special encapsulations for DSNF to ensure the loading in existing package designs. Especially the content of the encapsulations with damaged spent nuclear fuel must be avoided to enter in the inner space of the DPC, due to the possible higher amount of corrosive and radioactive material as well as greater quantities of water, which can be trapped in defect fuel rods. The main difference of the encapsulations for damaged spent nuclear fuel is that they have no replaceable sealing as tightness barrier. They have a specific welded lid. Therefor the tightness needs to be shown in the design approval process for all transport conditions especially for accident conditions, where high internal impact loads can occur. As German competent authority, BAM is responsible for the safety assessment of the mechanical and thermal design, the release of radioactive material and the quality assurance aspects of manufacturing and operation. Concerning the mechanical package design BAM carried out a comprehensive safety assessment for the specific encapsulations during the package design approval process of the commonly used DPC. For the proof of tightness of the welded lid no representative standards are available. For minor loads the German KTA standards can verify the tightness of a weld seam but only for low stresses. For higher impact loads physical tests are required. These tests were performed with representative drop tests and highly sensitive leak tests. The present paper gives an overview of the applied assessments by BAM and points out the main findings of the mechanical design for the welded sealing. Both verification procedures are described, on one hand with German standards for lower loads and on the other hand with physical tests for higher impact loads. The drop tests based on complex numerical pre-calculations by the applicant which result in optimized dimensions and properties of the test specimens and representative drop heights for the drop tests. The horizontal drop orientation with a plane-parallel impact on the unyielding basement was most challenging and led to specific adaptations during preparation and conduction of the drop tests performed by BAM. With leak tests and the corresponding test evaluation, it could be finally approved that the specific welded sealing of an encapsulations for DSNF is tight for all transport conditions. T2 - ASME PVP 2024 CY - Bellevue, WA, USA DA - 28.07.2024 KW - Tightness verification KW - Weld seams KW - Drop tests KW - Encapsulations for damaged spent nuclear fuel KW - Helium leak tests PY - 2024 SN - 978-0-7918-8851-3 SP - 1 EP - 10 CY - New York AN - OPUS4-61351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Winkler, H. P. A1 - Probst, Ulrich A1 - Ballheimer, Viktor A1 - Neumeyer, Tino T1 - Verification of design leakage rates for activity release calculation N2 - The mechanical and thermal loadings associated with the routine, normal and accident conditions of transport can have a significant effect on the leak tightness of the sealing system of transport casks for spent fuel and high radioactive waste. Applicants are requested by BAM to provide test programmes for verification of design leakage rates of the sealing system under the possible loads. Two test series initiated to clarify the dependency of the standard leakage rate on dynamic lid displacement as well as the dependency of the useful elastic recovery ru of a metallic seal on temperature and time, are outlined in this paper as examples of present investigations: Sliding tests simulating a lid displacement possible by a horizontal drop of the cask are carried out at the controlled drop test facility of BAM with test flange pairs equipped with metallic Helicoflex seals. For specification of covering values for the useful elastic recovery ru GNS has started a very comprehensive test programme with overall 70 metallic seals installed in test flanges which are stored for a period of one year at three different temperatures up to 150°C. This paper gives an overview about the current approach of BAM in the assessment of cask tightness and informs about the status of the running test series. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 2013-08-18 KW - Radioactive material KW - Safety assessment KW - Leakage rate KW - Leak tightness KW - Sealing behavior PY - 2013 SP - 1 EP - 7 PB - Omnipress AN - OPUS4-32194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Neumeyer, Tino A1 - Droste, Bernhard T1 - Design Approval of Special Form Radioactive Material- Important Aspects N2 - The design of a special form radioactive material has to resist a severe transport accident without undue loss or dispersal of radioactive material. Safety assessment by authorities competent for design approval has to include besides the required test program (impact, percussion, bending and heat test) also the evaluation of the quality management system for design, manufacture, testing, documentation, use, maintenance and inspection. These quality assurance measures have to assure that every specimen of the approved design is produced in the same verified quality and every specimen must be able to survive the severe mechanical and thermal tests without undue loss or dispersal of radioactive material at any time of its working life. All important aspects in the design approval procedure by BAM as the competent authority for approvals of special form radioactive material in Germany are summarized in a guideline published in 2014. This paper will give additional explanations to some aspects in safety assessment, e.g.: the applicability of leak test methods and the need to consider ageing aspects. T2 - PATRAM 2016 CY - Kobe, Japan DA - 18.09.2016 KW - Transport KW - Radioactive material KW - Safety PY - 2016 SP - Paper 4004-22 AN - OPUS4-39912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Karsten A1 - Favre, A. A1 - Hilbert, F. A1 - Quercetti, Thomas A1 - Neumeyer, Tino A1 - Weingart, Barbara T1 - Prototype testing of a protective structural packaging for 30B cylinder N2 - Three drop test campaigns have been performed with DN 30 Protective Structural Packaging (PSP) developed by DAHER NUCLEAR TECHNOLOGIES GmbH for the transport of natural, enriched and reprocessed uranium hexafluoride (up to 5 wt%) in 30B cylinders. The mechanical prototype testing is intended to demonstrate that the package DN30 complies with regulatory requirements under normal and hypothetical accident conditions of transport (NCT, ACT) relevant to IF, AF and B(U)F packages, respectively. The paper includes the results of the latest test campaign carried out in 2015-2016 at the drop test facility of BAM, Germany with new full scale prototypes of the DN30 PSP and 30B cylinders. Repetition of drop test sequences became necessary after changing to Polyisocyanurate foam as shock absorbing material with variable foam densities. Furthermore, the mechanical behavior of the UF6 content of the 30B cylinder is now simulated by a mixture of cement and steel grid as modified surrogate material; instead of small steel balls. The behavior of this new content simulation is assumed to be more realistic with respect to the properties of real UF6. T2 - PATRAM 2016, 18th International Symposium on the Packaging and Transportation of Radioactive Materials CY - Kobe, Japan DA - 18.09.2016 KW - Drop test KW - Packaging KW - Radioactive material KW - Uranium hexafluoride PY - 2016 SP - Paper 1018, 1 EP - 11 PB - INMM CY - Deerfield, Illinois, USA AN - OPUS4-37568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hilbert, F. A1 - Kuschke, Christian A1 - Goedecke, Thomas A1 - Neumeyer, Tino T1 - Drop testing of the NCS 45 T2 - PATRAM 2007, 15th International Symposium on the Packaging and Transportation of Radioactive Materials CY - Miami, Florida, USA DA - 2007-10-21 KW - Drop tests KW - Scale model PY - 2007 SP - 1 EP - 8 PB - Institute of Nuclear Materials Management AN - OPUS4-18644 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Droste, Bernhard A1 - Neumeyer, Tino A1 - Kowalewsky, Helmut T1 - Hoch- und Tieftemperatureignung von Elastomerdichtringen für Transport- und Lagerbehälter radioaktiver Stoffe T2 - Jahrestagung Kerntechnik `99 CY - Karlsruhe, Deutschland DA - 1999-05-18 PY - 1999 SN - 0720-9207 SP - 313 EP - 316 PB - Inforum AN - OPUS4-21598 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kowalewsky, Helmut A1 - Droste, Bernhard A1 - Neumeyer, Tino A1 - Burnay, S.G. A1 - Ball, M. H. A1 - Morton, D.A.V. A1 - Smith, P.N. A1 - Tuson, A.T. ED - Droste, B. ED - Kowalewsky, H. T1 - Safety assessment of leaktightness criteria for radioactive materials transport packages T2 - PATRAM 98 - 12th International conference on the packaging and transportation of radioactive materials CY - Paris, France DA - 1998-05-10 PY - 1998 VL - 2 SP - 543 EP - 550 PB - Nuclear Technology Publishing CY - Paris, France AN - OPUS4-21599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Neumeyer, Tino A1 - Droste, Bernhard T1 - Testing of sealed radioactive sources at BAM N2 - Requirements and test programs for sealed radioactive sources are specified in international standards for safety in transport and in use. Sealed sources which are approved as special form radioactive material according to the Transport Regulations, IAEA Safety Standards TS-R-1, must be able to withstand mechanical (9 m drop, percussion and bending) and thermal (800°C heat) tests without loss of radioactive content. The International Standard ISO 2919 provides a set of tests which classifies the sources for their safety in use. Performance tests specified in this standard are temperature (high and low), external pressure, impact, vibration and puncture tests. Each test can be applied at different levels of intensity depending on typical usage. As a criterion of pass or fail, leakage testing has to be done after each test. The poster gives an overview of BAM s comprehensive test equipment and experience in testing sealed radioactive sources. T2 - 3rd European IRPA Congress CY - Helsinki, Finland DA - 2010-06-14 KW - Radioactive KW - Sealed sources KW - Testing PY - 2010 SN - 978-952-478-551-8 IS - P18-07 SP - 2749 EP - 2754 CY - Helsinki AN - OPUS4-23420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumeyer, Tino T1 - Experimental Drop Testing of Waste Containers for the KONRAD Repository T2 - ICEM 2011 - 14th International Conference on Environmental Remediation and radioactive Waste Management CY - Reims, France DA - 2011-09-25 PY - 2011 AN - OPUS4-24449 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kuschke, Christian A1 - Neumeyer, Tino A1 - Wille, Frank A1 - Droste, Bernhard T1 - Mechanical/thermal package design safety assessment and manufacturing quality assurance of spent fuel transport cask NCS 45 T2 - WM2010 - 36th Annual radioactive waste management symposium CY - Phoenix, Arizona, USA DA - 2010-03-07 KW - Package design KW - Spent fuel transport cask KW - Safety assessment PY - 2010 SN - 978-0-9828171-0-0 SP - 1 EP - 13 CY - Tempe, AZ, USA AN - OPUS4-24344 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rolle, Annette A1 - Neumeyer, Tino T1 - Prüfung und Zulassung von radioaktiven Stoffen in besonderer Form N2 - Radioaktive Stoffe in besonderer Form (SFRM) sind nicht dispergierbare feste radioaktive Stoffe oder dichte Kapseln, die radioaktive Stoffe enthalten /1/. SFRM sind eine Kategorie innerhalb der verkehrsrechtlichen Vorschriften. Für die Beförderung zu Anwendern in der Industrie, Medizin und Forschung werden umschlossene radioaktive Stoffe (Strahler) gemäß ihrem aktivitätsabhängigen Gefahrenpotenzial verpackt. Strahler mit einer hohen Aktivität (> A2) erfordern entsprechend der verkehrsrechtlichen Vorschriften eine Beförderung in Typ B (U) Versandstücken, die als unfallsicher gelten. Alternativ besteht bis zu einer Aktivität < A1 die Möglichkeit der Beförderung in nicht unfallsicheren Typ A Versandstücken, wenn die Strahler nachweislich unfallsicher ausgelegt sind und eine Zulassung als SFRM vorliegt. Die Bundesanstalt für Materialforschung und –prüfung (BAM) ist gemäß GGVSEB §8 (2) /2/ in Deutschland die zuständige Behörde für die Prüfung und Zulassung radioaktiver Stoffe in besonderer Form. KW - Zulassung KW - Radioaktiv KW - Beförderung KW - Strahlenschutz PY - 2020 SN - 0947-434 X IS - 1 SP - 14 EP - 16 PB - TÜV Media CY - Köln AN - OPUS4-50763 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Quercetti, Thomas A1 - Wille, Frank A1 - Gröke, Carsten A1 - Neumeyer, Tino T1 - Design assessment, approval of management systems and ageing aspects of transport packages for radioactive material not requiring competent authority approval of design N2 - Most transports of radioactive materials are carried out with packages not requiring competent authority approval of design. These encompass – in accordance with the IAEA SSR-6 regulations – packages of the classification excepted, Industrial packages Type 1, 2 and 3 and Type A packages. Currently an upsurge in number and variation of these package designs can be seen in Germany, resulting from the phase out of nuclear energy in Germany as well as e. g. increased use of radioactive material for medical purposes. A design assessment regarding the package safety is required in the international IAEA SSR-6 regulations. BAM operates facilities for the performance of all regulatory tests required such as drop towers for a wide range of package masses and dimensions, fire test, leak tightness measurements and pressure test facilities. Experiences with several package types are shown. Additionally, IAEA SSR-6 requires the establishment of a management system for design, manufacture, maintenance, and repair of the packaging as well as for the preparation, consigning, loading, carriage, unloading and receipt of the package. Relevant for Germany, BAM has published guidance material on the process of management system acceptance in the technical guide BAM-GGR 016. The requirements encompass quality management plans for the manufacturing of packages including independent manufacturing surveillance and specific instructions for operation, maintenance, and repair of packagings. Examples for management system specifics and requirements are given. Since the latest edition of the IAEA SSR-6 regulations an ageing evaluation including systematic ageing management measures are required for all kind of package types. BAM is going to update the guidance material BAM-GGR 016 to support the stakeholders with relevant information to fulfil the ageing aspect for packages not requiring competent authority approval. The paper explains how the ageing aspect may be included in the safety evaluation process and the management system measures and will give an outlook for the future guidance material. T2 - 20th International Symposium on the Packaging and Transportation of Radioactive Materials (PATRAM 22) CY - Juan-Les-Pins, Antibes, France DA - 11.06.2023 KW - Typ KW - Radioactive material KW - Non-approved PY - 2023 SP - 1 EP - 8 AN - OPUS4-57703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Lars A1 - Scheidemann, Robert A1 - Neumeyer, Tino A1 - Neumann, Martin A1 - Komann, Steffen A1 - Wille, Frank T1 - Thightness Assessment of welded Lids for Encapsulations of damaged Spent Nuclear Fuel in the Design Approval Process of Dual-Purpose Casks (DPC) N2 - The disposal of spent nuclear fuel in Germany is ensured using dual-purpose casks (DPC) for transport and interim storage. The leak tightness of the DPC and resulting containment is one of the most important aspects. Additional encapsulations are required for damaged spent nuclear fuel (DSNF) to guarantee safe handling and a separate tight closure. Due to the general design of DPCs for standard fuel assemblies should special requirements be considered for the design of the encapsulations for DSNF to ensure the loading in existing package designs. The absence of a replaceable sealing in the tightness barrier is the main difference for the encapsulations for damaged spent nuclear fuel. Instead, they are welded shut with a lid. The leak tightness of the encapsulation shall be proven in the design approval process for all transport conditions. This is especially valid for accident conditions of transport, where high internal impact forces may occur. BAM as German competent authority is responsible for the safety assessment of mechanical and thermal design, retention of radioactive material and quality assurance aspects of manufacturing and operation. BAM carried out a comprehensive safety assessment concerning the mechanical package design. As there are no representative standards for verifying the leak tightness of a welded lid, two approaches were being pursued. Established German standards may be used for verifying the leak tightness of a weld - but limited to low stresses. Therefore, physical tests were required for higher impact loads. Representative drop tests and highly sensitive leakage tests were performed. The paper presents an overview of the containment assessment by BAM and points out the main findings for the design of welds regarding leak tightness. Both verification procedures are described, on one hand with German standards for lower loads and on the other hand with physical tests for higher impact loads. The leak tightness of the encapsulation weld could be approved based on leakage tests and a corresponding evaluation for all transport conditions. T2 - PATRAM 2025 CY - San Antonio, Texas, USA DA - 27.07.2025 KW - Transport packages KW - Tightness assessment KW - Welded lids KW - Encapsulations PY - 2025 VL - 2025 SP - 1 EP - 11 PB - Institute of Nuclear Materials Management (INMM) CY - Indianapolis AN - OPUS4-64023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Ballheimer, Viktor A1 - Neumeyer, Tino A1 - Wille, Frank T1 - Application of leakage rates measured on scaled cask or component models to the package containment safety assessment N2 - The containment systems of transport and storage casks for spent fuel and highlevelradioactive waste usually include bolted lids with metallic or elastomeric seals. The mechanical and thermal loadings associated with the routine, normal and accident conditions of transport can have a significant effect on the leak tightness of such containment system. Scaled cask models are often used for providing the required mechanical and thermal tests series.Leak tests have been conducted on those models. It is also common practice to use scaled component tests to investigate the influence of deformations or displacements of the lids and the seals on the standard leakage rate as well as to study the temperature and time depending alteration of the seals. In this paper questions of the transferability of scaled test results to the full size design of the containment system will be discussed. T2 - 19th International Symposium on the Packaging and Transportation of Radioactive Materials PATRAM 2019 CY - New Orleans, LA, USA DA - 04.08.2019 KW - Leakage rate KW - Transport packages KW - Seals KW - Radioaktive PY - 2019 SP - Paper 1147, 1 AN - OPUS4-49053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -