super duplex flanges

Benefits and Applications Super Duplex Flanges

Super Duplex is molybdenum (moly)-added austenitic-ferritic iron chromium-nickel alloy. As opposed to traditional austenitic stainless steels, it has good pitting resistance, and has excellent Tensile strength, and is high resistance to stress corrosion cracking at modest temperatures.

Super Duplex Flanges

A flange is an external or internal ridge between two pipes that enables pumps, pipes, valves, and other machinery which is attached to form a piping structure.

Duplex 2507 is a super duplex austenitic stainless steel grade. The 2507 Super Duplex Flange’s specific chemistry or chemical composition contains elements such as 25% chromium, 4% molybdenum, and 7% nickel in its alloy.

Super Duplex Flanges have high thermal conductivity and a low thermal expansion, as well as excellent resistance to chloride stress-related corrosion cracking. The high chromium, molybdenum, and nickel content of the Super Duplex Pipe Flange provides the flanges with improved or enhanced resistance to the crevice, pitting, and general corrosion.


Super Duplex include this type of flanges:

  • Lap Joint Flanges.
  • Socket Welding Flange.
  • Blind Flanges and Spectacle Blind.
  • Welding Neck Flange.
  • Long Welding Neck Flanges.
  • Threaded Flanges.
  • Orifice Flange.
  • Slip-on Flange.


Super Duplex Flange is also resistant to inorganic acids, which is important in the presence of chloride-containing materials. While the Super Duplex Flange can be used in dilute hydrochloric acid, it should not be exposed to concentrated hydrochloric acid. Super Duplex Flanges have increased pitting corrosion tolerance in salty settings, brackish waters, bleaching procedures, and certain food processing applications. Offshore marine requires components that can survive severe and harsh environments and are light in weight. Because of the added Nitrogen, Super Duplex Flanges have an improved microstructure, allowing for the fabrication of small and light-weight flanges that are simple on the wallet.


Where is Super Duplex Flanges applicable?

  • Super Duplex is particularly useful in applications for industries such as offshore, oil and gas as well as in sour wells. Heat exchangers, tubes/ pipes for production and handling.
  • Desalination plants heat exchangers and drains
  • Components which are structural and mechanical
  • FGD applications in the power sector,
  • Pipes that carry chloride-containing solutions,
  • Utility and industrial systems, shafts, fans, rotors, and press rolls will all benefit from the high corrosion fatigue strength.
  • Chemical tanker cargo containers, boats, plumbing, and welding consumables



  • High tenacity
  • Pitting and crevice corrosion resistance is excellent.
  • Resistance to stress corrosion cracking, corrosion fatigue, and degradation 
  • Outstanding chloride stress-corrosion resistance cracking.
  • Sulfide stress corrosion resistance is fine.
  • Austenitic steel is less thermal expansion and has better conductivity to heat.
  • Workability and weldability are outstanding.
  • High Absorption of an electricity