Sour-gas-resistant steels
Resistance to corrosive fluids
Dillinger’s sour-gas-resistant steels convince users with their high cleanness and their homogenous structure – the most important preconditions for the prevention of hydrogen-induced cracking (HIC) in pipelines and pressure vessels.
The Dillinger range for your needs
- Dillinger has broadly based know-how and many years of experience in the production of sour-gas-resistant steels.
- Sour-gas resistance is verified in our own laboratory.
- Sour-gas-resistant plate is produced in yield-strength classes up to 485 MPa, e.g. X70MS as per API Spec 5L, for the line pipe industry. Large plate thicknesses can be produced, and high degrees of cold forming achieved in pipe forming, depending on the specific requirement profile.
- Dillinger supplies its DICREST and DI-TANK sour-gas-resistant proprietary steels with various levels of HIC-resistance, and in large plate thicknesses and high item weights, for pressure-vessel engineering purposes. DICREST and DI-TANK meet the requirements for standardised pressure-vessel steels specified in the ASTM/ASME and EN 10028 standards.
Useful information on sour-gas-resistant steels
The occurrence of hydrogen-induced cracking (HIC) when steels are used in so-called sour-gas service is the result of an electrochemical corrosion reaction between an acidic fluid and the surface of the steel. Atomic hydrogen is evolved from hydrogen sulphide (H2S) in an acidic and moist environment and recombines to form molecular hydrogen (H2) at lattice defects and interfaces, such as non-metallic inclusions, segregations or micropores, for example. This hydrogen can then cause cracking in the material. Sour-gas-resistant steels have a high cleanness and a homogenous microstructure and thus provide fewer points of attack for the hydrogen. This is made possible by the use of specific processing routes, in combination with carefully harmonised quality-assurance provisions.
