Against the backdrop of dual carbon emissions, the hydrogen energy industry is rapidly taking off, with long-distance hydrogen pipelines becoming the core infrastructure of hydrogen energy storage and transportation systems. Unlike conventional natural gas pipelines, hydrogen molecules are small and easily diffuse, making them highly susceptible to hydrogen embrittlement and corrosion in steel, leading to decreased pipe toughness, cracking, and leaks. This places far more stringent requirements on pipeline materials, welding processes, and quality control than on conventional pipelines. This article outlines the core technical requirements and selection criteria for hydrogen pipelines, providing professional reference for hydrogen energy project procurement.
- 1. Key technical challenges of hydrogen pipelines: hydrogen embrittlement and hydrogen corrosion
- Under high-pressure hydrogen conditions, hydrogen atoms can penetrate into the interior of steel, accumulating at grain boundaries and defects. This leads to a significant decrease in the steel's plasticity and toughness, causing hydrogen-induced cracking, and this damage is irreversible. The higher the service pressure and the higher the purity, the more significant the risk of hydrogen embrittlement. Therefore, hydrogen pipelines cannot directly adopt the standards for ordinary natural gas pipelines.
- 2. Three core indicators for hydrogen pipeline selection
- Material purity and steel grade ratio: Low-carbon microalloyed clean steel must be selected, and the content of impurities such as sulfur and phosphorus must be strictly controlled to optimize the metallographic structure and reduce hydrogen embrittlement sensitivity from the base material level.
- Welding process control: The double-sided automatic submerged arc welding process is adopted to precisely control the composition and microstructure of the weld, ensuring that the weld toughness matches the base metal and preventing the weld from becoming a breakthrough point for hydrogen embrittlement.
- Stress relief process: Residual stress in the pipe is eliminated through processes such as online cold expansion and heat treatment, reducing stress sites where hydrogen atoms accumulate and improving the overall hydrogen resistance.
- 3. The selected model must match the current industry technical specifications.
- Currently, the " Technical Specification for Design of Pipes for Long-Distance Hydrogen Pipelines " in China has made clear requirements for the materials, design, and inspection of hydrogen pipelines. When selecting materials for projects, priority should be given to products from manufacturers that have participated in the drafting of standards and have accumulated technical expertise to ensure that the solutions are compliant and reliable.
- 4. Prioritize suppliers with proven track records from completed projects.
- Hydrogen pipelines are a high-end niche product, and laboratory data does not equate to engineering performance. Prioritizing manufacturers with actual experience supplying hydrogen energy projects and whose products have been validated under real-world operating conditions can significantly reduce the risk of trial and error in projects.
Company Reference: Hebei Haiganwei Steel Pipe focuses on the clean energy sector, specifically addressing the three major pain points of hydrogen embrittlement, hydrogen corrosion, and hydrogen leakage. It has optimized steel grade ratios, heat treatment, and welding processes, and its independently developed hydrogen transmission pipelines have been successfully applied to the Perdaman Ceres global large-scale urea base hydrogen service project in Australia, supplying all hydrogen transmission pipelines for the project. Furthermore, the company is a participating unit in the drafting of the "Technical Specification for Design of Pipes for Long-Distance Hydrogen Pipelines," possessing the capability to formulate industry standards for new energy pipelines and providing customized pipeline solutions suitable for various hydrogen energy projects.