This paper describes a general materials philosophy for pressure vessels in sour service applications as a function of the sour service severity. The development of pressure vessel steels with improved
resistance to the different forms of wet H2S cracking such as hydrogen induced cracking (HIC) or sulfide stress cracking (SSC) requires the attainment of high steel cleanliness and microstructural control. Guidelines are given on the measures necessary to obtain high resistance in the normalised carbon manganese steels commonly used in sour service. In addition, it is shown that quenched and tempered steels have the potential for improved performance through increased control of heat affected zone (HAZ) hardness after welding and uniform microstructure, offering excellent resistance to forms of cracking such as stress oriented hydrogen induced cracking (SOHIC).
Keywords: sulfide stress cracking, SSC, hydrogen induced cracking, HIC, stress oriented hydrogen induced cracking, SOHIC, steels, materials selection