Two of the most common corrosion problems encountered in wet H2S service are sulfide stress cracking (SSC) and hydrogen-induced cracking (HIC). The problems related to SSC were first recognized in the late
1940s and early 1950s. The interest in SSC was vastly increased after the tubing ftilure at Pincher Creek field in Alberta, Canada in 1949 and the well blowout at France’s Lacq field following the failure of the drill pipe and casing in 1951. Following a series of sour service pipeline failures in the Middle East in 1972 to 1974, the effect of HIC also caught the attention of the industry. Since then, effort has been made to combat these problems by researching the mechanism related to SSC and HIC and methods to improve materials resistance to such damage. Test methods such as NACE Standard TM0177 [1] and TM0284 [2], were developed and standardized by NACE to facilitate the process of evaluating and testing material for wet H2S service. These two standards provide a solid base for developing testing and research programs for materials evaluation and are two of the most widely used standards for sour service qualification. In order to filly utilize these standards, understanding of the corrosion and cracking mechanism and the usage of the standards are important. This paper attempts to address these issues and will discuss the background theories, proper usage, and limitation of the standards. In addition, information will be given on typical acceptance criteria in terms of linking test results to field applications.
Keywords : sulfide stress cracking, hydrogen-induced-cracking, hydrogen blistering, constant load, constant strain, hydrogen damage.