The deformation behaviour of the long-term exploited pipelines in simulated soil electrolytes imitates

Pipeline transportation of hydrocarbon energy is one of the cheapest and most environmentally friendly transport methods. In the context of the green energy transition and implementing ambitious plans to reduce carbon emissions. The issue of optimal future use of the released pipeline capacities arises. One promising option is to use existing pipeline networks to transport green hydrogen and methane-hydrogen mixtures. The pipeline steel is subject to defect accumulation during long-term operation, which causes degradation of physical and mechanical properties. The influence of operational degradation on the resistance to deformation of 19G and 17GS pipe steels in soil electrolytes of different chemical compositions was studied. It is shown that the strain growth in corrosive environments can be up to 30%, which will increase operational risks, especially in areas that run in structurally unstable soils. At the same time, the absolute values of the strain increase are in the range of 3...7% and are not very dangerous since they are within the range of tolerable damage. In the future, it will be advisable to study in more detail the behaviour of pipe steels after long-term operation in the environment of hydrogen gas and methane-hydrogen mixtures to assess the prospects for using existing pipelines for their transportation.