Sour Gas and Hydrogen Embrittiement Resistance of High-Strength UNS N07022 Alloy for Oil and Gas Applications

摘要

N07022 is a Ni-21Cr-17Mo (wt.%) alloy that has found success in applications requiring corrosion resistance and high strength. The attributes of N07022 alloy in the cold-worked (CW) condition make it an excellent candidate for many oil and gas applications. It has been incorporated in the NACE MR0175 / ISO 15156 and NACE MR0103 / ISO 17945 standards at the highest test levels. It has also shown resistance to the NACE Level VII environment with 5 g/L elemental sulfur at 205°C (401 °F) and to the demanding conditions of 25% NaCI + 1,000 psi (6.9 MPa) CO_2 + 1,000 psi (6.9 MPa) H_2S at 288°C (550°F). As higher strength alloys are becoming more common in high-pressure, high-temperature (HPHT) oil and gas service, there have been a number of reported failures involving precipitation-strengthened Ni-base alloys. These failures were attributed to hydrogen embrittiement. Recent results of sour gas and hydrogen embrittiement testing of CW N07022 alloy will be presented. The test results of CW N07022 alloy will demonstrate that it offers superior properties to precipitation-strengthened Ni-base alloys for demanding oil and gas applications.