Analysis and optimization of high-pressure hydrogen rubber O-ring sealing structures

Rubber seals are widely used in high-pressure hydrogen sealing applications. However, due to hydrogen’s low molecular weight and wide explosive limits range, seal failure can readily lead to combustion or explosion incidents. Therefore, this paper addresses the challenges of enhancing the damage resistance stability and sealing performance of rubber O-ring seals in high-pressure hydrogen environments. By comprehensively considering material hydrogen absorption expansion, mechanical property changes, and the influence of multiple structural parameters, a predictive model for high-pressure hydrogen sealing performance is established. Through orthogonal experimental design and weight matrix analysis, the performance evolution under the combined effects of five key variables—O-ring inner diameter, groove depth, groove top radius, sealing gap, and backup ring thickness—was systematically investigated. This revealed the sealing mechanism and structural parameter sensitivity of high-pressure hydrogen seals. Results indicate that comprehensive sealing performance can be significantly enhanced when the five key variables are set to 22.4 mm, 2.1 mm, 0.2 mm, 0.05 mm, and 1 mm, respectively.