Sour-Service & HIC-Resistant Steel
Sour-service steels are selected and manufactured to reduce susceptibility to hydrogen-related cracking in wet H2S environments.
Engineering basis
Low carbon equivalent, controlled sulfur, inclusion shape control, clean steelmaking and hardness limits are commonly used. HIC-resistant plate may use calcium treatment and strict segregation control.
Standards, grades or methods
NACE MR0175 / ISO 15156 governs materials for H2S-containing oil and gas production environments; project specifications may require HIC, SSC or SOHIC testing beyond base material standards.
Typical applications
Sour oil and gas pipelines, pressure vessels, separators, tanks, fittings and upstream/downstream process equipment.
Critical checks
Confirm environmental severity, hardness limits, HIC/SSC test requirements, weld hardness mapping, PWHT, consumables, chemical composition and plate through-thickness quality.
Good engineering practice
Use the current governing code or specification and verify manufacturer data, material traceability and project-specific requirements. Where safety, pressure containment or structural integrity is involved, obtain approval from the responsible engineer before changing material, process or acceptance criteria.
Element Folio engineering reference. Requirements vary by standard, project and jurisdiction.
