9.1 Komponenten für Energieträger
Filtern
Dokumenttyp
- Vortrag (41)
- Posterpräsentation (15)
- Zeitschriftenartikel (10)
- Beitrag zu einem Tagungsband (3)
- Beitrag zu einem Sammelband (1)
- Sonstiges (1)
Schlagworte
- Hydrogen (23)
- Hollow Specimen Technique (22)
- Hydrogen Embrittlement (17)
- TransHyDE (12)
- High-Pressure Gaseous Hydrogen (11)
- H2HohlZug (10)
- Wasserstoff (8)
- Hohlzugprobe (6)
- Microbiologically Influenced Corrosion (MIC) (6)
- Standardisation (6)
Organisationseinheit der BAM
- 9 Komponentensicherheit (71)
- 9.1 Komponenten für Energieträger (71)
- 9.4 Integrität von Schweißverbindungen (17)
- 4 Material und Umwelt (7)
- 4.1 Biologische Materialschädigung und Referenzorganismen (7)
- 9.6 Additive Fertigung metallischer Komponenten (5)
- 2 Prozess- und Anlagensicherheit (4)
- 2.1 Sicherheit von Energieträgern (4)
- 5 Werkstofftechnik (3)
- 5.1 Mikrostruktur Design und Degradation (3)
Paper des Monats
- ja (2)
A large explosion occurred at an oil refinery after a desulfurization reactor cracked, releasing hot, pressurized gasoline. The resulting explosions and fire caused extensive damage and injured some employees.
A 1.4 m crack adjacent to a weld seam at a reactor support bracket caused the release. The reactor shell exhibited distinctive circumferential bulging. The reactor was erected using mild steel. All material properties of the reactor shell complied with the regulations in effect at that time. Fractographic analysis of the main crack and smaller ones at the other support brackets revealed stepwise ductile fracture resulting from static loading. All well-known failure mechanisms for pressure vessel burst had proven wrong: overpressure, pressure cycles, overtemperature, creep, corrosion, external (cyclic) mechanical loads… Due to small spherical indentations on the inside of the reactor shell, a completely new failure mechanism was established and investigated:
During service, the reactor was partially filled with ceramic ball grading and catalyst. Gasoline was processed at 150–250 °C and ∼ 24 bar. Each of the reactor’s ∼ 20 operating cycles ran for several months until the catalyst was spent, after which the reactor was cooled, depressurized, emptied, and refilled. Upon heating, the thermal expansion of the steel shell (∼3 times greater than ceramic) created gaps that were filled as ceramic balls settled. During operation, the catalyst degraded and agglomerated with the ceramic balls, forming a rigid mass. Upon cooling, the rigid mass resisted the vessel’s thermal contraction, inducing circumferential tensile stresses and plastic deformation, resulting in permanent bulging of the vessel. Charpy impact energy near the welds was significantly reduced, attributed to thermal and strain aging in the bulged region. Progressive embrittlement and increasing plastic strain led to crack initiation and incremental ductile crack propagation at the support bracket welds over successive cycles. The fracture features were reproduced in laboratory tests at 200 °C. FEA analysis confirmed the proposed mechanism. Two identical vessels showed similar damage but had not yet failed. To prevent future damage in pressure vessels, this new failure mechanism needs to be incorporated into design, operating and inspection codes for pressure vessels possibly/partially filled with solids.
The diffusion of atomic hydrogen into metals can significantly affect the function and service life of components. Currently, however, there is no standardized procedure for analyzing hydrogen permeation through metals from the gas phase. The DIN EN ISO 17081 and ASTM G148 standards allow metallic materials to be tested using an electrochemical method. However, electrochemical methods are usually not practical for real-world applications, and measurement artifacts often occur due to surface reactions. A standardized method that investigates hydrogen permeation from the gas phase has the advantage that both the temperature and the hydrogen pressure can be precisely controlled over a wide range. This allows for the calculation of temperature- and pressure-dependent diffusion parameters (diffusivity, permeability, and solubility). The presentation showcases the activities at BAM on hydrogen gas permeation (experimental techniques) and their impact on standardization activities.
The future of the hydrogen infrastructure largely depends on the reliable operation and integrity of metallic components under high-pressure conditions. Since hydrogen embrittlement (HE) can degrade the mechanical properties of materials, detailed material qualification under realistic operating conditions is necessary. However, common testing methods in autoclaves are complex and costly, and are only available to a limited extent. The hollow-specimen technique has emerged as a cost- and time-efficient alternative. Its applicability has been demonstrated for a wide range of materials, including ferritic pipeline steels and their welds. The H2HohlZug project addressed critical knowledge gaps that had previously prevented full standardization. Surface roughness and microstructural damage to the inner hole were identified as dominant factors contributing to hydrogen-induced material degradation. Furthermore, "elongation at pressure drop" was defined as a precise criterion for characterizing embrittlement. An international round robin involving ten laboratories confirmed the method's high reproducibility. These results provide the technical foundation for revising the ISO 7039:2024 standard (led by German DIN) and pave the way for the global, cost-effective standardization of hydrogen testing using hollow specimens.
Stahlkomponenten können bei Einsatz in Wasserstoffatmosphäre eine verminderte Lebensdauer aufweisen, da Wasserstoff die Duktilität und das Rissverhalten der Werkstoffe negativ beeinflussen kann. Um diese wasserstoffunterstützte Schädigung ganzheitlich zu bewerten, müssen sowohl mikroskopische Gefügeeigenschaften als auch makroskopische Betriebsbedingungen berücksichtigt werden. Durch die innovative Testplattform „ModuH2Pipe@BAM“, als Teil des Reallabors „H2Netzte“, verfügt die BAM, neben Labortests, auch über die Infrastruktur zur Prüfung an realen Bauteilen. Diese europaweit einzigartige Prüfeinrichtung ermöglicht es, reale Bauteile unter praxisnahen und kombinierten Bedingungen wie Durchströmen, Pulsieren oder Vorkonditionieren gezielt zu untersuchen.
Hydrogen produced from renewable energy sources is a key low-carbon energy carrier for decarbonizing the energy sector and supporting the transition toward a hydrogen economy. One important pathway for this transition is the injection of hydrogen into existing natural gas networks, as emphasized in European hydrogen roadmaps and strategies. In this context, the SHIMMER project aims to support safe and efficient hydrogen integration by developing a publicly available database on European gas infrastructure. The database currently includes 262 records representing approximately 43,195 km of gas pipelines, with information such as material grade, design pressure, inner diameter, installation year, operational parameters, standards, pilot projects, and reference studies. By harmonizing data from open sources and participating transmission and distribution system operators, the SHIMMER database provides a structured basis for assessing hydrogen compatibility across countries and supports future research on hydrogen injection into gas transmission and distribution systems.
From research to a standard: The hollow specimen technique for high-pressure hydrogen gas testing
(2026)
Hydrogen infrastructure relies strongly on metallic components operating under high pressures, including pipelines, storage vessels, compressors, and valves. Ensuring the structural integrity of these materials in hydrogen environments is crucial, as hydrogen can significantly degrade the mechanical properties of structural components, leading to premature and sometimes catastrophic failure under conditions that would otherwise be well within their safe operating range. These degradation phenomena are broadly referred to as hydrogen-assisted degradation and encompass mechanisms such as hydrogen embrittlement (HE). Rigorous material testing under representative hydrogen exposure conditions is therefore essential to qualify structural alloys for hydrogen service. However, the accepted and standardised test methods for determining the influence of gaseous hydrogen on metallic materials describe complex and costly procedures available only to a limited number of facilities worldwide.
The hollow specimen technique offers a simple and economical alternative, confining hydrogen within a sealed internal hole machined through the specimen gauge section, rather than surrounding the specimen in a pressure vessel. This reduces hydrogen volumes, safety requirements, and infrastructure demands substantially, making the method suitable for widespread adoption and increasing experimental throughput. Initial studies demonstrated the feasibility of the technique for assessing hydrogen effects in metallic materials, leading to the establishment of the standard ISO 7039:2024. However, open questions relating to specimen geometry, inner hole manufacturing and surface condition, and gas purity prevented its full standardisation for hydrogen testing. The H2HohlZug project, conducted under the German research initiative TransHyDE and coordinated by BAM, was established to systematically close these gaps.
The project results have demonstrated that the hollow specimen technique is a viable, reproducible, and practical method for qualifying metallic materials under high-pressure gaseous hydrogen. By systematically addressing the identified knowledge gaps that prevented the standardisation of the technique for hydrogen testing, the project has established the technical foundation required for a comprehensive revision of ISO 7039:2024. The ongoing revision of ISO 7039, led by DIN, represents the direct translation of the project results into a normative framework, bringing the hollow specimen technique closer to widespread adoption as a reliable and accessible alternative to conventional autoclave based hydrogen testing.
We investigated the phase transformations during butt-welding of supermartensitic steel plates with help of Neutron Bragg-Edge Imaging (NBEI). Gas tungsten arc welding (GTAW) was used with a motorized torch allowing for automated weldments. The austenitization in the heat affected zone (HAZ) could be clearly visualized at λ = 3.95 Å, a wavelength smaller than the Bragg edge wavelengths of both austenite and martensite phases. The re-transformation into the martensitic phase during cooling was clearly detected. However, we observed an unexpected additional change in transmission at λ = 4.4 Å, a wavelength larger than the wavelengths of the Bragg edges of both the martensitic and austenitic phases. We attribute this change to the temperature dependence of coherent scattering at a crystal lattice. The observed two-dimensional attenuation map corresponds well with a temperature distribution modelling by software macros in ANSYS. Here, the absolute temperature values could be achieved by calibrating the modelled attenuation with help of a thermocouple placed at the steel plate. This allows in return for a direct two-dimensional temperature reading based on the relation between the neutron attenuation caused by the inelastic neutron scattering and the sample temperature. The method was extended further to 3D mapping of
temperature distribution in bulk y steel samples.
Das Kompetenzzentrum H2Safety@BAM forscht zu sicherheitstechnischen Fragestellungen über die gesamte Wertschöpfungskette von Wasserstoff. Der Fokus liegt hierbei insbesondere auf Untersuchungen zu Materialeignung und -kompatibilitäten, neuen Konzepten für die Bauteilsicherheit und -prüfung, Zertifizierungen, Sensortechnik und Analytik sowie der Prozess- und Anlagensicherheit. Das Poster gibt einen Praxisnahen überblick über die Aktivitäten.
The analysis of pipeline failures due to Microbiologically Influenced Corrosion (MIC) is challenging due to the complex interaction of many influencing parameters including pipeline operation conditions, fluid chemistry and microbiology, as well as the analysis of corrosion features and products. To help address this challenge, an expert system was developed to assist specialists and non-specialists in screening internal pipeline corrosion failures due to the threat of MIC. To that end, 15 MIC subject matter experts (with a total of 355 man-years of accumulated MIC based experience) were recruited to evaluate a total of 65 MIC failure cases based on real-life scenarios. These case study parameters and the expert elicited results were input into an Artificial Neural Network (ANN) model to create a model system which can screen whether a given failure scenario is one of three outcomes: a) failure is likely due to MIC, b) failure is likely not due to MIC, or c) the conclusion is inconclusive (analysis needs more data/information). The model system had an overall accuracy of 74.8% and it showcases that knowledge from subject matter experts can be captured in a reasonably effective way to screen for possible MIC failures. Based on that, this presentation will provide details of the model development process and key results to date. Important considerations regarding the level of confidence of the diagnoses and variation between expert opinion will also be discussed alongside with ideas on how to improve the model for field applicability.
Underground hydrogen storage (UHS) is a strategic step towards implementing the hydrogen economy. Achieving the required infrastructure by 2050 necessitates advancements in hydrogen-dedicated assets and the evaluation of existing infrastructure. The unique conditions in UHS require an experimental set-up to simulate UHS operating conditions, which allows to assess the readiness of current storage and transmission lines for hydrogen, and develop new technologies for material-resistance, operational-simulations, and risk-assessments. Currently, UHS-experiments for microbiologically-influenced-corrosion (MIC) are performed in standard autoclaves with relatively high volumes/pressures; which do not allow for an extensive evaluation of the system over the experiment, but rather their initial and final conditions. To overcome such limitations, the novel UHS-simulation-set-up developed is designed in a way that (1) it allows for liquid addition during the test, enabling the study of biocides or the evaluation of operating setups, as well as (2) it permits liquid/-gas sampling during the test, allowing for more efficient monitoring of testing conditions and a better understanding of the process over time. Additionally, a low-pressure-release function is added. It prevents degradation of polymers, corrosion products, microorganism during after the simulation is complete. Therefore, preserving the integrity of samples for subsequent evaluation, which otherwise would not be possible.
