Periodic Reporting for period 1 - PilgrHYm (PRE-NORMATIVE RESEARCH ON INTEGRITY ASSESSMENT PROTOCOLS OF GAS PIPES REPURPOSED TO HYDROGEN AND MITIGATION GUIDELINES)
Período documentado: 2024-01-01 hasta 2025-06-30
Transporting natural gas through pipelines has been shown to be safe and efficient for decades. However, decarbonizing the European industry and reducing carbon emissions will require a significant portion of the existing pipeline infrastructure to be used for transporting gaseous hydrogen under high pressure across the continent, from production sites to end users. The pipelines, originally designed for natural gas, are not considered H2-ready, and Transmission System Operators must demonstrate their compatibility with hydrogen. The existing standards, such as ASME B31.12 are often viewed as overly conservative and not conducive to the development of pure hydrogen networks.
PilgrHYm is an ambitious R&D project that seeks to develop a pre-normative framework to support the development of a European standard. The project aims to conduct a comprehensive testing program on small-scale laboratory specimens, focusing on 8 base materials, 2 welds, and 2 heat-affected zones that are representative of the EU gas grids. These specimens will be selected after a thorough review by TSOs to address safety concerns, lack of regulations, codes, and standards, as well as research gaps related to the compatibility of current pipelines with hydrogen. PilgrHYm's ultimate goal is to provide quantified data on more than 70% of the EU grid and refine existing norms, codes, and standards by reducing over-conservatism and ensuring the safety and reliability of flaw assessment methodologies.
To reach the previously stated goals, PilgrHYm has established 7 technical and non-technical specific objectives (SO), interconnected with the project's results, key performance indicators and work packages.
- SO1: Develop a database of material characterization testing on representative steel grades of the EU gas grids, including tensile strength, fracture toughness and fatigue crack growth (FCG) properties.
- SO2: Establish a harmonized testing protocol to support the repurposing of natural gas lines to hydrogen.
- SO3: Develop a numerical modelling approach for simulating and predicting hydrogen assisted fracture and fatigue.
- SO4: Optimize a more realistic FCGR (Fatigue Crack Growth Rate) master curve for fitness-for-service assessment purpose, in particular for low ΔK values corresponding to the actual operating domain of the EU gas grids.
- SO5: Identify existing and/or innovative technologies for mitigation compatible with operational constraints.
- SO6: Engage with stakeholders to ensure cooperation and awareness.
- SO7: Facilitate the adoption and exploitation of PilgrHYm results by the academic community, technology developers and end-users.
The results of PilgrHYm will serve as the baseline for a harmonized European solution. This project represents a significant step forward in the development of a comprehensive European standard for transporting hydrogen through pipelines and will be instrumental in the successful decarbonization of the European industry and reducing carbon emissions.
PilgrHYm is an ambitious R&D project that seeks to develop a pre-normative framework to support the development of a European standard. The project aims to conduct a comprehensive testing program on small-scale laboratory specimens, focusing on 8 base materials, 2 welds, and 2 heat-affected zones that are representative of the EU gas grids. These specimens will be selected after a thorough review by TSOs to address safety concerns, lack of regulations, codes, and standards, as well as research gaps related to the compatibility of current pipelines with hydrogen. PilgrHYm's ultimate goal is to provide quantified data on more than 70% of the EU grid and refine existing norms, codes, and standards by reducing over-conservatism and ensuring the safety and reliability of flaw assessment methodologies.
To reach the previously stated goals, PilgrHYm has established 7 technical and non-technical specific objectives (SO), interconnected with the project's results, key performance indicators and work packages.
- SO1: Develop a database of material characterization testing on representative steel grades of the EU gas grids, including tensile strength, fracture toughness and fatigue crack growth (FCG) properties.
- SO2: Establish a harmonized testing protocol to support the repurposing of natural gas lines to hydrogen.
- SO3: Develop a numerical modelling approach for simulating and predicting hydrogen assisted fracture and fatigue.
- SO4: Optimize a more realistic FCGR (Fatigue Crack Growth Rate) master curve for fitness-for-service assessment purpose, in particular for low ΔK values corresponding to the actual operating domain of the EU gas grids.
- SO5: Identify existing and/or innovative technologies for mitigation compatible with operational constraints.
- SO6: Engage with stakeholders to ensure cooperation and awareness.
- SO7: Facilitate the adoption and exploitation of PilgrHYm results by the academic community, technology developers and end-users.
The results of PilgrHYm will serve as the baseline for a harmonized European solution. This project represents a significant step forward in the development of a comprehensive European standard for transporting hydrogen through pipelines and will be instrumental in the successful decarbonization of the European industry and reducing carbon emissions.
The project began on January 1st, 2024. As of now, six out of the eight Work Packages have started as scheduled.
In 2024, two literature reviews were conducted on innovative modeling approaches and standards for material mechanical testing in pressurized hydrogen gas. These reviews contributed to the project’s objectives related to experimental (testing protocol) and modeling aspects.
This effort was complemented by a questionnaire sent to European TSOs to collect extensive data on the transmission steel networks present in Europe. The gathered information helped to identify the 10 materials to be tested in the main testing campaigns (the 2 other materials being identified at an earlier stage for the round robin test).
This marks a significant step forward in the project's execution.
In 2024, two literature reviews were conducted on innovative modeling approaches and standards for material mechanical testing in pressurized hydrogen gas. These reviews contributed to the project’s objectives related to experimental (testing protocol) and modeling aspects.
This effort was complemented by a questionnaire sent to European TSOs to collect extensive data on the transmission steel networks present in Europe. The gathered information helped to identify the 10 materials to be tested in the main testing campaigns (the 2 other materials being identified at an earlier stage for the round robin test).
This marks a significant step forward in the project's execution.
1. Robust testing procedures in gaseous H2: PilgrHYm will conduct a round robin test on different specimen geometries to identify discrepancies in existing test methods. By systematically assessing key test parameters (e.g. specimen constraint, load vs. displacement control, and gas impurities), the project will establish robust, standardized testing procedures to enhance result comparability and safety in H2 environments.
The round robin test is ongoing.
2. Applicability and limitations of non-standardized testing methods (hollow specimen): PilgrHYm will scientifically evaluate hollow-specimen tests as a safer, cost-effective alternative to traditional autoclave testing. Comparative studies, including finite element simulations, will define best practices for specimen preparation, testing, and data interpretation, leading to validated guidelines for assessing hydrogen embrittlement in pipeline steels.
The testing protocol on hollow specimen has been defined in 2024 for the round robin test. The work is ongoing.
3. Innovative modeling approaches for hydrogen embrittlement: PilgrHYm will develop a standardized calibration procedure for hydrogen-assisted fracture models, extending them to fatigue damage prediction. By optimizing computational efficiency (e.g. cycle-jumping strategies) and improving understanding of cyclic degradation mechanisms, the project will enable more accurate lifetime predictions and reduce material testing costs.
A literature review on innovative modeling approaches (D4.1) has been performed in 2024. The development of the models is ongoing.
4. Testing campaign for transmission gas grids: PilgrHYm conducted in 2024 a comprehensive survey of European gas grid conditions and materials, leading to a representative test matrix for key pipeline steels.
By ensuring direct transferability of laboratory results to real-world conditions, the project will fill critical data gaps and provide a validated database for assessing H2 compatibility in Europe’s gas infrastructure.
The round robin test is ongoing.
2. Applicability and limitations of non-standardized testing methods (hollow specimen): PilgrHYm will scientifically evaluate hollow-specimen tests as a safer, cost-effective alternative to traditional autoclave testing. Comparative studies, including finite element simulations, will define best practices for specimen preparation, testing, and data interpretation, leading to validated guidelines for assessing hydrogen embrittlement in pipeline steels.
The testing protocol on hollow specimen has been defined in 2024 for the round robin test. The work is ongoing.
3. Innovative modeling approaches for hydrogen embrittlement: PilgrHYm will develop a standardized calibration procedure for hydrogen-assisted fracture models, extending them to fatigue damage prediction. By optimizing computational efficiency (e.g. cycle-jumping strategies) and improving understanding of cyclic degradation mechanisms, the project will enable more accurate lifetime predictions and reduce material testing costs.
A literature review on innovative modeling approaches (D4.1) has been performed in 2024. The development of the models is ongoing.
4. Testing campaign for transmission gas grids: PilgrHYm conducted in 2024 a comprehensive survey of European gas grid conditions and materials, leading to a representative test matrix for key pipeline steels.
By ensuring direct transferability of laboratory results to real-world conditions, the project will fill critical data gaps and provide a validated database for assessing H2 compatibility in Europe’s gas infrastructure.