Corrosion Behavior of Sulfide-resistant Casing Steel P110SS under Condition of High Containing H₂S/CO₂ and Cl^-

High temperature/pressure autoclave was used to simulate the high containing H2S/CO2 corrosion environment, the influences of Cl- on corrosion rate, sulfide stress cracking and hydrogen induced cracking of sulfide-resistant casing steel P110SS were studied. The results show that the corrosion rate of P110SS increased in the first and then decreased with the increase of Cl- concentration, the corrosion rate reached the maximum when the Cl- concentration was 50 000 mg/L; P110SS did not ethibit cracks of sulfide stress cracking and hydrogen induced cracking, the sulfide stress cracking and hydrogen induced cracking sensitivities of P110SS were low. The reasons were the existance of homogenious tiny tempered sorbite microstructure of P110SS, addition of beneficial elements Cr, Mo, Ti, Nb and V and low content of harmful elements of S and P.