Study on Applicability of Oil Casing Material 110Cr13S for Offshore Oil and Gas Fields

In order to evaluate the applicability of 110Cr13S oil casing steel in offshore oil and gas field development projects，the corrosion behavior of 110Cr13S steel in simulated high temperature，high pressure，CO2 and H2S coexisting corrosion environments under well of deep water oil and gas fields was studied using exposure corrosion tests，in-situ electrochemical tests，stress corrosion tests.Scanning electron microscopy，energy spectrometer，electrochemical workstation，slow strain rate tensile testing machine were used to study the corrosion morphology，corrosion product composition，electrochemical behavior and slow strain rate tensile curves of 110Cr13S oil casing steel under the conditions of 129.5 ℃，H2S partial pressure of 358 Pa and CO2 partial pressure of 2.754 MPa.Results showed that the average corrosion rate of 110Cr13S steel was 0.004 4 mm/a under the simulated deep sea oil and gas field well conditions，and a dense and complete passivation film was formed on the surface of the sample，which presented good corrosion resistance and excellent resistance to sulfide stress corrosion cracking.Therefore，110Cr13S oil casing steel was suitable for selecting oil casing materials for oil and gas well development under conditions of deep water，high temperature，high pressure，CO2 and H2S coexisting conditions.