TY - CONF A1 - Askar, Enis T1 - Competence centre h2safety@bam N2 - In this presentation the current focus areas of the competence centre H2Safety@BAM are shown. The fields of competence include “Material properties and compatibility”, “Process and plant safety”, “Component testing, component safety and approval” as well as “Sensors, analytics and certified reference Materials. Moreover, the cross-cutting activities regarding “Education and training” and the testing possibilities and planed test facilities at the Test Site for Technical Safety (BAM TTS) are presented. T2 - VDMA P2X4A: P2X Technik-Treffen CY - Online meeting DA - 14.09.2023 KW - Hydrogen KW - Test area hydrogen safety KW - ModuH2Pipe PY - 2023 AN - OPUS4-58333 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Asna Ashari, Parsa T1 - Exploring the Technological Innovation System for Hydrogen Technologies - Four Essays on the Roles of Research, Innovation, and Safety N2 - Presentation of the doctoral thesis held at the PhD Colloquium of the Chair of Innovation Management, Freie Universität Berlin. Hydrogen has recently come into political and industrial focus due to its potential to advance the transition to a net-zero economy. Despite this recognized potential, the market ramp-up of hydrogen technologies has not yet been realized at large. Therefore, this thesis attempts to investigate how advances in hydrogen research, innovation, and safety link up to market formation using the Technological Innovation Systems (TIS) and Quality Infrastructure (QI) frameworks. Thereupon, the thesis formulates several recommendations for transitioning to a hydrogen economy. T2 - PhD Colloquium of the Chair of Innovation Management (Freie Universität Berlin) CY - Berlin, Germany DA - 09.01.2024 KW - Hydrogen KW - Research and innovation KW - Innovation system KW - Safety PY - 2024 AN - OPUS4-59400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernardy, Christopher T1 - Thermal Radiation Investigations of Real-Scale Hydrogen Jet Flames at High Pressure N2 - In order to reduce global warming, the use of hydrogen as a renewable energy source is becoming more important. To enable this transition, unprecedently large amounts of hydrogen need to be safely transported and stored. Since hydrogen is usually stored and transported under pressure, one scenario to be considered is the release of hydrogen from a leakage with subsequent ignition. The resulting jet flame must be characterized with respect to the thermal radiation emitted into the environment to define safety distances. Various models that characterize the resulting flame shape and radiation already exist in the literature, but these are mainly based on empirical data from hydrocarbon jet flames. To verify the applicability of these models to hydrogen, real-scale tests are carried out at the BAM Test Site for Technical Safety (BAM-TTS) with the aim to assess the flame geometry and the emitted thermal radiation. Parameters such as leakage diameter (currently up to 30 mm), pressure (currently up to max. 250 bar) and mass flow (up to max. 0.5 kg/s) are varied. In particular, the focus will be laid on the measurement and modelling of the thermal radiation. The challenge here is the characterization of the flame geometry in an open environment and its impact on the thermal radiation. Existing heat radiation data from literature are mostly based on unsteady outflow conditions. The experimental setup used here allows for the generation of a steady-state outflow for several minutes and thus a direct comparability with existing (steady-state) models. Furthermore, stationary outflow tests with hydrocarbons (methane) were also carried out, which are intended to serve as reference tests for checking flame models based on hydrocarbon data. Following from the experimental investigations, modelling parameters such as the Surface Emissive Power (SEP) and the radiant heat fraction for hydrogen and methane will be compared to literature data. T2 - Center for Hydrogen Safety Americas Conference, American Institute of Chemical Engineers CY - Las Vegas, NV, USA DA - 21.05.2024 KW - Thermal radiation KW - Hydrogen KW - Release KW - Jet flame PY - 2024 AN - OPUS4-60195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernardy, Christopher T1 - Real scale safety investigations of hydrogen jet flames at high pressure N2 - In order to reduce the human footprint of CO2 emissions and limit global warming effects hydrogen combustion is becoming increasingly important. To enable fuel cells and gas turbines to operates this carbon free fuel, unprecedently large amounts of hydrogen need to be produced and safely transported and stored. The investigation of the effects of accidents involving hydrogen is therefore becoming of outmost importance. Since hydrogen is usually stored and transported under pressure, one scenario to be considered is the release of hydrogen from a leakage with subsequent ignition. The resulting jet flame must be characterized with respect to the thermal radiation emitted into the environment to define safety regulations. Various models that characterize the resulting flame shape and radiation already exist in the literature, but these are mainly based on empirical data from hydrocarbon jet flames.[1-4] To verify these models, a H2 Jet Flame project conducted at BAM, is investigating the safety of momentum driven hydrogen jet flames. For this purpose, large-scale tests are carried out at the Test Site Technical Safety (BAM-TTS). The object of the investigations is to assess the effects of real scale release scenarios regarding flame geometry and the thermal radiation emitted. Parameters such as release angle, leakage diameter (currently 1 mm to 10 mm), pressure (currently up to max. 250 bar) and mass flow (up to max. 0.5 kg/s) are varied. In addition, influences such as the type of ignition, ignition location as well as delayed ignition can also be investigated. The gained knowledge will be compared with existing jet flame models, to validate these and identify a possible need for further development. In particular, the focus will be laid on the thermal radiation of hydrogen flames. The challenge here is the visualization and characterization of the flame geometry in an open environment. Visualization is performed using infrared (IR) camera systems from at least two viewing angles. Measurements of the heat radiation of jet flames, which can be found in the literature, are mostly based on unsteady outflow conditions.The experimental setup used here allows for the generation of a steady-state outflow for several minutes and thus a direct comparability with existing (steady-state) models. Furthermore, the tests can be carried out for comparative measurements with hydrocarbons (methane, etc.) as well as mixtures of hydrogen and hydrocarbons. T2 - European PhD Hydrogen Conference 2024 (EPHyC2024) CY - Gent, Belgium DA - 20.03.2024 KW - Hydrogen KW - Release KW - Jet flame KW - Thermal radiation PY - 2024 AN - OPUS4-59908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernardy, Christopher T1 - Investigation of the thermal radiation from hydrogen jet flames N2 - For industrial applications dealing with hydrogen, the definition of safety distances and the assessment of possible hazards emanating from releases is mandatory. Since hydrogen is usually stored and transported under pressure, one scenario to be considered is the momentum driven release of hydrogen from a leakage with subsequent ignition. In this scenario, the emitted heat radiation from the resulting jet flame to the surroundings has to be determined to define adequate safety distances. For hydrocarbon flames, different jet flame models are available to assess the hazards resulting from an ignited jet release. Since hydrogen flames differ from hydrocarbon flames in their combustion behavior, it has to be checked if these models are also applicable for hydrogen. To evaluate the accuracy of these models for hydrogen jet flames, tests at real-scale are carried out at the BAM Test Site for Technical Safety (BAM-TTS). Herein, the flame geometry and the heat radiation at defined locations in the surroundings are recorded for varying release parameters such as leakage diameter (currently up to 30 mm), release pressure (currently up to max. 250 bar) and mass flow (up to max. 0.5 kg/s). The challenge here is the characterization of the flame geometry in an open environment and its impact on the thermal radiation. Existing heat radiation data from the literature are mostly based on unsteady outflow conditions. For a better comparability with the steady state jet flame models, the experiments presented here are focused on ensuring a constant mass flow over the release duration to obtain a (quasi) stationary jet flame. In addition, stationary outflow tests with hydrocarbons (methane) were also carried out, which are intended to serve as reference tests for checking flame models based on hydrocarbon data. T2 - 15th International Symposium on Hazards, Prevention and Mitigation of Industrial Explosions (ISHPMIE) CY - Naples, Italy DA - 10.06.2024 KW - Hydrogen KW - Release KW - Jet flame KW - Thermal radiation PY - 2024 AN - OPUS4-60512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernardy, Christopher T1 - Large scale safety investigations of hydrogen jet flames N2 - For industrial applications dealing with hydrogen, the definition of safety distances and the assessment of possible hazards emanating from releases is mandatory. Since hydrogen is usually stored and transported under pressure, one scenario to be considered is the momentum driven release of hydrogen from a leakage with subsequent ignition. In this scenario, the emitted heat radiation from the resulting jet flame to the surroundings has to be determined to define adequate safety distances. For hydrocarbon flames, different jet flame models are available to assess the hazards resulting from an ignited jet release. Since hydrogen flames differ from hydrocarbon flames in their combustion behavior, it has to be checked if these models are also applicable for hydrogen. To evaluate the accuracy of these models for hydrogen jet flames, tests with a horizontal outlet at large-scale are carried out at the BAM Test Site for Technical Safety (BAM-TTS). Herein, the flame geometry and the heat radiation at defined locations in the surroundings are recorded for varying release parameters such as release pressure (currently up to max. 250 bar), mass flow (up to max. 0.175 kg/s) at an outlet diameter of 30 mm. The challenge here is the characterization of the flame geometry in an open environment and its impact on the thermal radiation. Existing heat radiation data from the literature are mostly based on unsteady outflow conditions. For a better comparability with the steady state jet flame models, the experiments presented here are focused on ensuring a constant mass flow over the release duration (currently 120 s) to obtain a stationary jet flame. In addition, stationary outflow tests with hydrocarbons (methane) were also carried out, which are intended to serve as reference tests for checking flame models based on hydrocarbon data. The comparison of the flame geometry shows that hydrogen jet flames with the same outlet mass flow have a greater flame length (average deviation of 15 %) but a smaller flame diameter than methane jet flames (average deviation of 17 %). Conclusions regarding thermal radiation show that the proportion of total combustion energy emitted as thermal radiation is lower for hydrogen (xrad = 0.04–0.08) than for methane (xrad = 0.05–0.1). A comparison of the surface emissive power (SEP) of the jet flame shows a SEP range of 7 kW/m²-15 kW/m² for hydrogen and 3 kW/m² - 9,5 kW/m² for methane. T2 - H2 Safety - Colloquium - Process and Plant Safety CY - Online meeting DA - 19.02.2025 KW - Hydrogen KW - Release KW - Radiant heat fraction KW - Jet flame KW - Thermal radiation PY - 2025 AN - OPUS4-62779 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernardy, Christopher T1 - Experimental investigation of large scale hydrogen diffusion jet flames N2 - Hydrogen is a promising alternative to natural gas in industrial energy applications which would serve the goal of limiting global warming. However, wide application of hydrogen requires specific safety considerations taking into account that hydrogen is stored and transported under much higher pressure than natural gas. Thus, one scenario to be considered for hazard assessment is a sudden release of hydrogen from a leakage or safety valve and its subsequent ignition. For hydrocarbon flames, various jet flame models are available. However, hydrogen flames significantly differ from hydrocarbon flames in their combustion behavior, so that the applicability of these models to hydrogen has to be investigated. For that purpose, reals scale tests were carried out at the BAM Test Site Technical Safety. In addition, hydrocarbon jet flames (methane) were investigated. In these tests, the flame geometry and the thermal heat radiation were investigated for a release angle of 90°, for different release pressures (up to 220 bar) and mass flows (up to 0.175 kg/s). While existing heat radiation data from the literature are mostly based on unsteady outflow conditions and/or releases in still air, the experiments presented here are focused on ensuring a constant mass flow over the release duration under realistic free field conditions (with wind influence). This allows a better comparability with the stationary jet flame models and assessment of wind influence on model predictions. A number of parameters such as the surface emissive power of the jet flame and the radiant heat fraction were determined. A detailed comparison of the obtained experimental results with literature radiation models was performed. Good agreement between experimental and literature data was found for hydrogen whereas significant differences were identified for methane. Based on the investigations, empirical equations for modelling jet flames could be derived. T2 - American Society of Mechanical Engineers - Turbomachinery Technical Conference & Exposition CY - Memphis, TN, USA DA - 15.06.2025 KW - Hydrogen KW - Release KW - Thermal radiation KW - Diffusion jet flame PY - 2025 AN - OPUS4-63454 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bühling, Benjamin T1 - Recent Developments of Fluidic Ultrasonic Transducers at BAM N2 - Ultrasonic measurement technology has become indispensable in NDT. In order to reduce measurement time and extend the application to other materials, contactless ultrasound is the subject of many different research groups. Department 8 has been researching successfully in this field for years. A novel approach is based on so-called fluidic devices. These devices can be used to perform binary logic operations with the help of natural flow instabilities. Hence the abbreviated name, Fluidic (FLUID+LogIC). Only a pressure reservoir of the used fluid is required as energy supply. This enables the production of very robust actuators that generate ultrasonic signals in an extremely energy efficient way. The presentation includes the research results of the ZIM innovation project OsciCheck. The original idea will be presented and its application on different building materials is validated. Beyond this, the possible application areas are much larger and a detailed outlook is given to discuss the future potential of fluidic ultrasonic actuators. T2 - Abteilungsseminar Abteilung 8 CY - Berlin, Germany DA - 23.09.2021 KW - Uultrasound KW - Non-destructive testing KW - Fluidic devices KW - Hydrogen KW - Ranging KW - Harsh environments PY - 2021 AN - OPUS4-53356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chulvi Iborra, Katherine T1 - Pd(II)-LMOF based material for the sensing of molecular hydrogen in gas phase N2 - Current interest in hydrogen gas as an energy source is growing due to its attractive properties such as high chemical energy density and the fact that its combustion produces water as by-product, qualifying this gas as an appealing clean energy source. In particular, the use of molecular hydrogen in automotive applications such as the hydrogen internal combustion engine (HICE) or hydrogen fuel cells is an excellent clean alternative. Despite these promising opportunities, hydrogen gas has a distinct disadvantage as an everyday energy medium, that is, it is highly flammable. Hydrogen processing apparatuses should therefore be constantly monitored so that leaks are immediately detected. The implementation of direct sensing systems for H2(g) is thus a decisive factor for its application and acceptance as a clean energy source. Because the automotive market alone is already a mass market, these sensors do not only have to be reliable, robust and dimensionally small, but operation has to be simple and the device itself cost-effective. In addition, very low detection limits are a must as already escape of small quantities of H2(g) is directly related to public health and safety. Besides electrochemical or semiconductor sensors, optical sensors are especially appealing because the equipment is usually simple and accessible, easily miniaturized and measurements can be performed in situ and in real time. If one cannot rely for instance on metallic palladium as interacting matrix, a major challenge for optochemical hydrogen sensors is to find a suitable material that fulfils all the requirements mentioned above and undergoes a dedicated indication reaction with H2(g). One such alternative can be Metal-Organic Frameworks (MOFs) which constitute a predefined, organized, mesoporous structure built up from metal ions and organic bridging ligands. With a myriad of building blocks being available, MOFs can be equipped with internal H2 reception sites that shall allow for selective and sensitive indication. For instance, if Pd ions are implemented in such a way that they express open metal sites (OMS), these OMS shall possess a strong affinity for hydrogen. If light absorbing and emitting organic ligands are additionally chosen, luminescent MOFs (LMOFs) can result that are perfect candidates for optical sensors, as changes at the analyte reception site can be effectively transduced into a measurable signal. In this contribution, we intended to discuss the development of a new luminescent sensor material for the detection of the highly flammable H2(g). This sensor material is based on an LMOF assembled from Pd(II) and aromatic bridging ligands, the advent of hydrogen at the OMS in the LMOF producing distinct variations in the material’s optical properties. T2 - 24th Congress and General Assembly of the International Union of Crystallography CY - Hyderabad, India DA - 21.08.2017 KW - Optical sensor KW - Hydrogen KW - LMOF PY - 2017 UR - http://www.iucr2017.org/abstract/myaccount/pdf/iucr2017-abstract-0b61b4c101d7bf652ae5b0dffd66e5fd.pdf AN - OPUS4-42362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Prestressed Concrete Structures with ConcentratedTendons- Structural Damage due to Hydrogen-Induced Stress Corrosin Cracking N2 - In the course of the deconstruction of the "Bridge of the 20th anniversary of the GDR" at the Altstädter Bahnhof in Brandenburg a. d. Havel, new information on the initiation of hydrogen-induced stress cracks was obtained. BAM was commissioned by the Brandenburg State Road Administration to participate in a corresponding joint project which is financed by the Federal Ministry for Digital and Transport. The added value of the new information gained in this project goes beyond the specific structure. It describes unexpected new damage patterns that can be transferred to other structures with concentrated tendons (tendon block method and Baur-Leonhardt method) and were previously unknown in this form. These should be made known to other developers to enable them to initiate any necessary actions. T2 - Consec 2024 CY - Chennai, India DA - 24.09.2024 KW - Corrosion KW - Spannstahl KW - Hydrogen KW - Korrosion PY - 2024 AN - OPUS4-61305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Prestressed Concrete Structures with Concentrated Tendons - Structural Damage due to Hydrogen-Induced Stress Corrosion Cracking N2 - In the course of the deconstruction of the "Bridge of the 20th anniversary of the GDR" at the Altstädter Bahnhof in Brandenburg a. d. Havel, new information on the initiation of hydrogen-induced stress cracks was obtained. BAM was commissioned by the Brandenburg State Road Administration to participate in a corresponding joint project which is financed by the Federal Ministry for Digital and Transport. The added value of the new information gained in this project goes beyond the specific structure. It describes unexpected new damage patterns that can be transferred to other structures with concentrated tendons (tendon block method and Baur-Leonhardt method) and were previously unknown in this form. These should be made known to other developers to enable them to initiate any necessary actions. T2 - Eurocorr 2022 CY - Berlin, Gemany DA - 29.08.2022 KW - Korrosion KW - Corrosion KW - Hydrogen KW - Stress Cracking PY - 2022 AN - OPUS4-55613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Einfluss von Korrosionsprozessen auf die Verbundfestigkeit Feuerverzinkter Betonstähle in der Erstarrungsphase von Beton N2 - Die Wechselwirkung von hoher Alkalität und feuerverzinktem Betonstahl in der Frischbetonphase generiert einen Störung in der Verbundzone. diese Störung basiert sowohl auf der Wasserstoffentwicklung in der Frischbetonphase bis zur diffusionskontrollierten Decksschichtbildung als auch auf die erstarrungsverzögernde Wirkung von Zinkionen auf die CSH-Phasenbildung. Diese werden zwangsläufig infolge anfänglicher starker Korrosionsprozesse frei, und reichern sich in der Verbundzone an. Hier kann es beim normgerechten Ausschalen nach 24h zu weiteren Störungen des Haftverbundes kommen das davon Auszugehen ist das die Erstarrung der CSH-Phasen in der Verbundzone noch nicht begonnen hat. T2 - Forschungsbeiratssitzung der Forschungsvereinigung Feuerverzinkung CY - Darmstadt, Germany DA - 04.12.2025 KW - Korrosion KW - Verzinkter Betonstahl KW - Hydrogen PY - 2025 AN - OPUS4-65054 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Inhibition of hydrogen evolution on galvanized reinforcement in fresh concrete by addition of potassium permangante N2 - Due to the EUdirective53/2003/EEC,which has been in force since 17th January, 2005, restricts the soluble chromate content in cements to amaximum value of 2ppm. This ammount is to low to inhibit the hydrogen evolutuion by the cathodic partial reaction in fresh concrete. T2 - Eurocorr 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Corrosion KW - Galvanized reinforcement KW - Hydrogen PY - 2019 AN - OPUS4-48934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Seifert, Lando A1 - Müller, Thoralf T1 - Stress corrosion test in thiocyanate solution with galvanostatic current N2 - Prüfung von Spannstählen hinsichtlich ihrer Anfälligkeit gegenüber wasserstoffinduzierter Spannungsrisskorrosion in kürzeren Zeiträumen. Gewährleistung der Dauerhaftigkeit mittels neuartiger elektrochemischer Prüfverfahren und galvanostatischer Kontrolle und Wasserstoffbeladung T2 - Meeting ISO TC17 SC16 WG8 CY - Online meeting DA - 11.01.2023 KW - Hydrogen KW - Corrosion PY - 2023 AN - OPUS4-56854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ekici, Nilsah T1 - Introduction of The SHIMMER Database for Safe Hydrogen Injection in The European Natural Gas Infrastructure N2 - An important step in the transportation strategy for hydrogen is its injection into the existing natural gas grid, which allows accelerating the transition to a low-carbon economy, in other words, hydrogen economy. The European Commission has established hydrogen roadmaps and strategies that emphasize the safe and efficient integration of hydrogen into the natural gas network to support this transition. In line with the objectives of the road map, several funded projects have been established, among others – the Safe Hydrogen Injection Modelling and Management for European Gas Network Resilience (SHIMMER) project. One of the main goals of this project is establishing a database containing a comprehensive repository of information regarding materials, standards, European pilot projects, and operational conditions parameters for the European gas network gathered from open sources as well as transmission and distribution system operators participating in the project. The SHIMMER database has an extensive structure consisting of 262 pipeline entries, each with details such as length, design pressure, inner diameter, and installation year and more. The following contribution elaborates on how the SHIMMER database was established as reliable source of information to be available for the public. The database allows consistent assessments of hydrogen compatibility across different countries, offering a structured framework to help overcome the challenges inherent to the assessments of the components for the injection of hydrogen across Europe. Further, the SHIMMER database provides a valuable information source for future research on the European gas networks. T2 - ICHS 2025 CY - Seoul, South Korea DA - 22.09.2025 KW - Database KW - Hydrogen KW - Gas Grid KW - Low-carbon KW - Pipeline Steel PY - 2025 AN - OPUS4-64288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - El Harrab, Hayat A1 - Askar, Enis A1 - Franken, T. A1 - Mauss, F. T1 - Experimental and Reaction Kinetic Study of Hydrogen Ignition Behavior at Ignition Limits N2 - The paper presents the results of the experimental and reaction kinetic investigation of hydrogen ignition at different pressures, highlighting its non-linear behaviour and effects of radical wall termination. The reaction kinetic simulation predicts the three characteristic ignition limits caused by radical and thermal auto-ignition and is in close agreement with the experimental measurements. The introduction of radical wall termination in the reaction mechanism allowed us to investigate the effect of the autoclave wall and vessel size on the hydrogen ignition behaviour. The first ignition limit is determined by the chain initiation reaction H_2+O_2→2 OH and shows a strong sensitivity towards wall termination of O, H and OH radicals. The third ignition limit is dominated by the reaction paths HO_2+HO_2→H_2 O_2+O_2 and H_2 O_2+M→2 OH+M which is why it shows a strong sensitivity towards wall termination of HO₂ and H₂O₂ radicals. The second ignition limit is influenced by the wall termination of O, H, OH, HO2 and H2O2 radicals. Increasing the radical wall termination rate by increasing the adsorption rate of the radicals at the wall leads to an increase of the auto-ignition temperature at the same pressure. T2 - 13th Mediterranean Combustion Symposium CY - Corfu, Greece DA - 01.06.2025 KW - Hydrogen KW - Auto-ignition Temperature KW - Radical Wall Termination Reaction KW - Ignition Limit PY - 2025 AN - OPUS4-64762 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erxleben, Kjell T1 - Component test for the assessment of in-service welding on/onto pressurized hydrogen pipelines N2 - Hydrogen is seen as the energy carrier of the future. Therefore a reliable infrastructure to transport hydrogen in a large scale is needed. A so called European hydrogen backbone out of long distance transmission pipelines is planned by European countries to create a hydrogen transport infrastructure. Due to economic reasons this will be achieved by new build pipelines such as repurposed natural Gas (NG) pipelines, converted to hydrogen useage. A general suitability for hydrogen service of low alloyed pipeline steel, as it is used for NG service today, is given. But in case of necessary in-service welding procedures in terms of e.g. hot-tapping and stoppling, the risk of a critical hydrogen uptake into the pipe materials due to much higher temeperatures while welding and the possibility of hydrogen embrittlement (HE) needs to be closely investigated. The presentation gives an overview of the current H2-SuD project, investigating the feasability of in-service welding on future hydrogen pipelines. Therefore, component-like demonstrators were developed to test (I) the additional hydrogen uptake due to in-service welding under hydrogen pressure and (II) to measure the temperature field due to different welding parameters and demonstrator geometries, especially on the inner pipe wall surface. Collected data will be used to validate a numerical simulation of the thermal field and additionally the hydrogen diffusion in the pipeline material. T2 - Presentation at The University of Manchester CY - Manchester, United Kingdom DA - 12.09.2025 KW - In-service KW - Hydrogen KW - Pipeline KW - Welding PY - 2025 AN - OPUS4-64129 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erxleben, Kjell T1 - Hydrogen determination in welded metallic materials: Necessity and challenges N2 - In the course of tomorrow's hydrogen-based energy transition, the construction of the corresponding infrastructure will play a central role. The majority of materials used to date are typically welded for component fabrication. In that context, steels are widely applied and can be prone to hydrogen embrittlement. For the evaluation of any hydrogen effect on, for example, the mechanical properties of a welded metallic material, the hydrogen content must be precisely determined. According to ISO 3690, carrier gas hot extraction (CGHE) can be used. In addition to the pure quantification of hydrogen, thermal desorption analysis (TDA) with varied heating rates can be used to determine and evaluate the bonding state at microstructural defects in the material. For both techniques, experimental and measurement influences have to be considered, which have a great effect on the result. For CGHE, for example, ISO 3690 suggests different sample geometries as well as minimum extraction times. The present study summarizes results and experiences of numerous investigations with different sample temperatures and geometries (ISO 3690 type B and cylindrical TDA samples) regarding: the influence of the sample surface (polished/welded), measurement accuracies depending on the sample volume. In particular, a deviating extraction temperature to the set temperature, can significantly falsify the measurement results. Based on the results, methods are shown to quickly reach the desired extraction temperature without having to physically interfere with the measurement equipment. This serves to substantially improve the reliability of hydrogen measurement through increased signal stability and accelerated hydrogen desorption. In general, an independent temperature measurement with dummy samples for the selected heating procedure is advisable to exclude possible unwanted temperature influences already before the measurement. In addition (and way more important), the methods described can be transferred directly to industrial applications. T2 - Eurocorr 2023 - The European Corrosion Congress CY - Brussels, Belgium DA - 27.08.2023 KW - Hydrogen KW - Carrier gas hot extraction KW - Welding KW - ISO 3690 KW - Measurement PY - 2023 AN - OPUS4-58305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erxleben, Kjell T1 - Repair welding of in service hydrogen pipelines N2 - In the course of tomorrow's hydrogen-based energy transition, the construction of the corresponding infrastructure will play a central role. In that context, large diameter long-distance transmission pipelines for hydrogen will be the backbone in the European Union with service pressures from 70 to 90 bar (e.g., depending on national regulations). It is a major goal to rededicate the existing LNG infrastructure despite the necessity of new pipelines. From that point of view repairing of such transmissions pipelines via welding can be necessary. For the LNG infrastructure, it is state of the art that repair welding is conducted at pipelines under service, i.e., the LNG is still flowing as pressurized gas in the steel pipes. The reason is that a shut-down of large diameter pipelines is not so easy or sometimes impossible. In fact, as long no oxygen enters the pipeline, there would be any combustion or (in the worst case) explosion. At the moment, it is entirely open if current repair welding procedures for LNG pipelines can be transferred to pure hydrogen pipelines. In opposite to LNG, hydrogen can be way easier absorbed to the pipeline steels and diffuses through the material. If it accumulates in susceptible regions, i.e., in the welded joint, hydrogen assisted embrittlement could occur. The planned welding procedure requires a so-called preheating and maintenance of the weld joint of up to 300°C for several hours. This temperature is way higher compared to the typical service temperature of max. 40 to 50°C at operational pressures of 100 bar. In accordance to API 941, these low-alloyed pipeline steels are subjected to short-term service loads, which they are not designed for. For that reason, a collaborative project between BAM and DVGW (German Association for Gas and Water professions) was initiated in 2022 to answer the following questions by experiments and numerical simulation of: (1) How many hydrogen is additionally absorbed during the heating of the material to max. 300°C under remaining operational pressures? (2) Is the hydrogen concentration sufficient to reach a critical condition? (3) Which material and weld microstructure is the most susceptible? (4) Is there a significant difference in the repair welding behavior of LNG pipelines that had been already in use for long-term? (5) Which welding parameters and joint dimensions must be ensured for safe repair welding repair of typical pipelines? For that reason, the present study gives an overview on the current practice in repair welding of in-service pipelines, the industrial importance of this topic for the hydrogen-based energy transition and summarizes first results. T2 - Eurocorr 2023 - The European Corrosion Congress CY - Brussels, Belgium DA - 27.08.2023 KW - Hydrogen KW - Repair Welding KW - Pipeline KW - In-service KW - High-pressure PY - 2023 AN - OPUS4-58334 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erxleben, Kjell T1 - Component test for safety assessment of in-service welding on / onto pressurized hydrogen pipelines N2 - Hydrogen is the energy carrier of tomorrow for a fossil-free future. This requires a reliable transport infrastructure capable of transporting large quantities of hydrogen, e.g. for the steel and chemical industries. In addition to the construction of new pipelines, the conversion of existing natural gas (NG) networks is an essential part of global hydrogen strategies. The transport of hydrogen is fundamentally different from that of NG, as hydrogen can be absorbed into the pipeline material. Given the known effects of hydrogen embrittlement, the compatibility of the materials for the proposed pipelines (typically low alloy steels in a wide range of strengths and thicknesses) must be investigated. However, pipelines require frequent maintenance, repair, or the need to install additional outlets. In some cases, it is necessary to perform welding on or to the pipelines while they are still in service, i.e. with active gas flow under high pressure, such as the well-known "hot tapping". This in-service welding poses challenges for hydrogen operations in terms of additional hydrogen absorption during welding and material compatibility. The challenge can be roughly divided into the possible austenitization of the inner pipe material exposed to hydrogen, which can lead to sufficient hydrogen absorption, and the welding itself, which causes an increased temperature range. Both lead to a significant increase in hydrogen solubility and diffusivity of the respective materials compared to room temperature. In this context, knowledge about hot tapping on hydrogen pipelines is scarce due to the lack of operational experience. Fundamental experimental investigations are required to investigate the transferability from natural gas to hydrogen pipeline networks. For this reason, the present study presents a specially designed mock-up / demonstrator concept for the realistic assessment of the welding process conditions. T2 - Materials Week 2025 CY - Frankfurt am Main, Germany DA - 02.04.2025 KW - In-service KW - Hydrogen KW - Pipeline KW - Repair welding PY - 2025 AN - OPUS4-62874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -