Mechanical properties of a wide range of pipe steels under influence of pure hydrogen or hydrogen blended with natural gas

Hydrogen economy considers hydrogen as a substantial fraction of a nation's energy and services. This could happen in the future if hydrogen can be produced from domestic energy sources economically and in an environmental-friendly manner. Hydrogen can also be used as fuel in stationary fuel cell systems for buildings, emergency power or distributed generation. Hydrogen transport is generally made by pipelines. This solution is preferable than transport on road by truck for security reasons. The addition of hydrogen in natural gas could have an impact on the materials degradation over time especially those used for the storage, transport and distribution of natural gas. The compatibility of these materials with natural gas including of hydrogen is dependent on the proportion of hydrogen added into the gas and is assessed with regard to several criteria: - permeation of hydrogen through metallic materials; - loss of integrity of these materials and adaptation of follow-up actions in service, surveillance and maintenance of equipment. This paper is devoted to the effect of hydrogen embrittlement (HE) caused by adding hydrogen into natural gas network on its design, maintenance, supervision and maximum allowable service pressure (MAOP) for smooth and damaged pipes. •Effect of hydrogen embrittlement (HE) on pipe steels. •Influence on maximum allowable service pressure. •Influence on defect assessment. •Influence on surveillance and maintenance.