Objective Seal rings and gaskets are deemed indispensable sealing components for the safe operation of pure hydrogen/ hydrogen-enriched compressed natural gas pipelines. Therefore, investigating their performance in hydrogen environments holds great significance for the safe operation of these pipelines.

Methods This study focused on reviewing the advancements in research concerning seal rings and gaskets both in China and abroad. It delved into pivotal aspects, including prevalent seal materials for hydrogen environments, the mechanism of hydrogen permeation through seal rings accompanied by hydrogen absorption induced swelling and blister fracture, as well as the compression resilience and creep relaxation of gaskets in non-hydrogen environments, and hydrogen embrittlement of gaskets within hydrogen environments.

Results Current researches on the properties of seal rings and gaskets in non-hydrogen environments have achieved promising progress. However, since pure hydrogen or hydrogen-enriched compressed natural gas pipelines are still in the stage of initial development, researches on the properties of seal rings and gaskets in these environments are deficient, and many weak points relating to this area are requiring urgent care.

Conclusion Hydrogen permeation through rubber O-rings occurs at the molecular level, and this process is influenced by gas pressure and external temperatures. Notably, carbon black and silicon dioxide, serving as filling materials, exhibit significant variations in hydrogen absorption within rubber materials. This necessitates a deeper examination of alternative filling materials and additives to understand their effects on hydrogen absorption. The volumetric expansion of rubber seal materials is observed in hydrogen environments, involving distinct mechanisms of swelling induced by hydrogen absorption and blister fracture. Acknowledging sudden drops in ambient pressure as an indispensable condition for blister fracture and transparent EPDM rubber as the main object of the blister fracture research, this paper advocates further investigation into other hydrogen-compatible rubber materials and the impact of varying hydrogen blending ratios on O-ring swelling. It also underscores the deficiency of in-situ mechanical experimental research on gaskets in contact with hydrogen, emphasizing the crucial need to establish a quantifiable relationship between hydrogen blending ratios and the mechanical performance parameters of gaskets.