IN-SERVICE DEGRADATION OF GAS TRUNK PIPELINE X52 STEEL

摘要

The following in-bulk material degradation modifying the mechanical and corrosion-mechanical properties of X52 steel exploited for 30 years in gas trunk pipelines has been established: - the decrease in resistance to brittle fracture, revealed by drop of impact strength, reduction of area, fracture toughness and resistance to SCC, HE and HIBG; - the anomalies of mechanical behaviour, specific to the in-service embrittlement of metal: the decrease in the resistance to brittle fracture simultaneously with the decrease in hardness; the opposite change of the plasticity parameters, the decrease in the RA accompanied by the increase in elongation;