Super Duplex Steel

Super Duplex Pipes & Tubes

This is a Duplex alloy stainless steel designed to feature high strength, resistance to pitting, stress corrosion cracking, erosion corrosion and corrosion fatigue, crevice corrosion and strong weldability.

Super Duplex Applications

Oil and gas industry equipment, Offshore platforms, heat exchangers, process and service water systems, fire-fighting systems, injection and ballast water systems, Chemical process industries, heat exchangers, vessels, and piping, Desalination plants, high pressure RO-plants and seawater piping, Mechanical and structural components, high strength, corrosion-resistant parts, Power industry FGD systems, utility and industrial scrubber systems, absorber towers, ducting, and piping.

Super Duplex Corrosion Resistance

The high chromium and molybdenum content of Super Duplex makes it extremely resistant to uniform corrosion by organic acids like formic and acetic acid. Super Duplex also provides excellent resistance to inorganic acids, especially those containing chlorides. The pitting Resistance equivalent of Super Duplex, calculated by PREN = Cr + 3.3Mo + 16N, will exceed 40 in most material forms.

Forms of Super Duplex

Sheet, Plate, Bar, Pipe & Tube (welded & seamless), Fittings (i.e. flanges, slip-ons, blinds, weld-necks, lapjoints, long welding necks, socket welds, elbows, tees, stub-ends, returns, caps, crosses, reducers, and pipe nipples), Welding Wire and Welding Electrode

Properties of Super Duplex
  • Ferritic-Austenitic stainless steel.
  • Excellent corrosion resistance against general corrosion, stress corrosion cracking, corrosion fatigue, pitting, crevice and erosion corrosion and possessing very high mechanical strength properties.
  • Good weldability, post weld heat treatment not necessary.
  • Max. Temperature for long periods of service: 280°C (536°F) / (300°C/572°F possible for short periods).
  • Surface condition for optimum corrosion resistance: pickled or machined.

  • Standard for Super Duplex
    Alloy Designation
    UNS
    BS
    EN
    Basic
    DIN
    JIS
    Trade Name
    ASTM
    Alloy S32750 S32760   1.4410 25Cr-7Ni-4Mo-0.3N     SAF 2507 A789