Safety for H2 Transport in Welded Low-Alloy Gas Pipelines
- Steel gas pipelines are to be used in the future for the transport of hydrogen (H) or for its blending in natural gas. For the use of existing pipeline systems, as well as their adaptation and expansion with modern steels to the end user, it is necessary to investigate the extent to which hydrogen is absorbed by the material or welded joints, depending on the gas composition and changing temperature and pressure stresses, and can reduce their ductility, in order to exclude an unexpected brittle failure in the form of hydrogen-assisted cracking. So far, in-situ tests of H-absorption under continuous mechanical stress have been carried out using slow strain rate tests (SSRT) with full-section test specimens in high-pressure autoclaves. The high safetyrelated laboratory costs associated with this prevent cost-effective series testing for industry. Initial studies show that hollow tensile specimens (HTS) SSRT are a viable alternative through the defined adjustment of gases and pressuresSteel gas pipelines are to be used in the future for the transport of hydrogen (H) or for its blending in natural gas. For the use of existing pipeline systems, as well as their adaptation and expansion with modern steels to the end user, it is necessary to investigate the extent to which hydrogen is absorbed by the material or welded joints, depending on the gas composition and changing temperature and pressure stresses, and can reduce their ductility, in order to exclude an unexpected brittle failure in the form of hydrogen-assisted cracking. So far, in-situ tests of H-absorption under continuous mechanical stress have been carried out using slow strain rate tests (SSRT) with full-section test specimens in high-pressure autoclaves. The high safetyrelated laboratory costs associated with this prevent cost-effective series testing for industry. Initial studies show that hollow tensile specimens (HTS) SSRT are a viable alternative through the defined adjustment of gases and pressures via the inner bore hole. To this end, the following key questions need to be addressed, (1) representation of real stress scenarios of welded pipes on HTS, (2) the effect of the gas composition (H2/CH4) on H absorption and degradation, (3) the influences and interaction of different weld seam structures under continuous and cyclically changing stress, (4) the possibility of integrating into a practical test concept for the evaluation of welded steels, and (5) the material behaviour of existing pipelines compared to modern steels. This work, which is being carried out as part of the IGF project no. 22884, focuses on a systematic investigation of the boundary conditions temperature, pressure and H2 partial pressure as well as steel grade and strain rate in correlation with realistic conditions. The experimental investigations show significant, and in dependence of the strain rate, different pronounced effects, in particular due to the temperature and the H2 partial pressure on the deformation capacity of the examined materials. With this, the technology should be further developed for further questions, in particular with regard to weld microstructure, in order to establish a simple, economical test procedure based on HZP-SSRT with regard to the H-readiness of welded steel pipelines by means of corresponding guidelines and transfer to standards. Ultimately, users, especially SMEs such as testing laboratories, should be involved in the development of the hydrogen economy as part of the energy transition, which underlines the high relevance for society as a whole.…


| Autor*innen: | Julien Witte |
|---|---|
| Koautor*innen: | Gero Fey, Dirk Schröpfer, Arne Kromm, Thomas Kannengießer |
| Dokumenttyp: | Posterpräsentation |
| Veröffentlichungsform: | Präsentation |
| Sprache: | Englisch |
| Jahr der Erstveröffentlichung: | 2025 |
| Organisationseinheit der BAM: | 9 Komponentensicherheit |
| 9 Komponentensicherheit / 9.2 Versuchsanlagen und Prüftechnik | |
| DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Angewandte Physik |
| Freie Schlagwörter: | High-strength steel; Hollow tensile specimens (HTS); Hydrogen safety / transport; Slow strain rate testing (SSRT); Welded hydrogen pipeline safety / integrity |
| Themenfelder/Aktivitätsfelder der BAM: | Energie |
| Energie / Wasserstoff | |
| Veranstaltung: | 5th International Conference on Metals and Hydrogen |
| Veranstaltungsort: | Ghent, Belgium |
| Beginndatum der Veranstaltung: | 14.10.2025 |
| Enddatum der Veranstaltung: | 16.10.2025 |
| Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
| Datum der Freischaltung: | 22.12.2025 |
| Referierte Publikation: | Nein |

