Blending hydrogen in urban gas pipeline system: Investigation of the hydrogen compatibility of PE pipeline material

• In-situ tensile, creep, relaxation tests of PE100 in H 2 environment were conducted. • MD simulations were conducted to study the mechanism of hydrogen effect. • H 2 has no obvious effect on the mechanical performance of PE100. • H 2 and temperature have no coupling effect on the performance of PE100. The transportation of hydrogen to downstream users through the existing medium-low pressure polyethylene (PE) urban gas pipeline is an important stage of the utilization of hydrogen energy. However, hydrogen molecules may permeate into the PE materials, leading to deterioration of the mechanical properties and hydrogen leakage, risking the safety of PE hydrogen pipelines. In order to ensure the safety of medium-low pressure PE hydrogen pipelines, this paper investigates the hydrogen compatibility of PE100 material in a hydrogen environment through molecular simulations, in-situ tensile, creep and relaxation tests. The effect of hydrogen permeation and the coupling effect of hydrogen and temperature are studied. Results show that hydrogen has no obvious deterioration effect on PE100 material in the hydrogen environment of 14∼50°C and 0∼4 MPa.