You are here:

Super Duplex.

Super Duplex F53 and F55 Valves for Corrosive Petrochemical Applications

Super Duplex A182 F53, A182 F55, A890 Gr. 5A and A890 Gr. 6A Valves

Looking for a valve in this exotic alloy? Find it in the following configurations: Ball, Butterfly, Cast, Check, Control, Cryogenic, Custom made, Foot, Forged, Gate, Globe, Needle, Plug, and Safety relief, as well as Strainers.

Due to their ability to resist corrosion, alloy valves made of super duplex are often quite useful in various industrial processes including seawater systems and desalination plants. These corrosion-resistant valves are extremely functional in marine conditions such as subsea, offshore, and platform work. Also, these severe service valves are perfect in the chemical industry, especially when dealing with a variety of corrosive agents such as the following:

  • chlorides used in flue-gas cleaning
  • steam
  • fatty acids
  • concentrate brine
  • sea water
  • pulp water
  • potable water
  • pulp liquors at 220°F (104°C)
  • sulfuric acid (35-40% @ 185°F (85°C), plus 5% organics)
  • sulfuric acid (15-30% @ 140-160°F (60-71°C))

Lastly, these high-alloy valves are advantageous when the Pitting Resistance Number (PREN) is required.

Super duplex, used in exotic alloy valves, is a common name for a wide range of materials. Made of a 50/50 mixed microstructure of austenitic and ferrite, super duplex stainless steel is much stronger than austenitic and ferritic steel grades that have similar corrosion resistant properties. This increased strength is caused by the augmented chrome and nickel content in their composition. The super duplex stainless steel used in exotic alloy valves ranges in type and grade dependent on the method the raw material was developed and dependent on the international standards and norms used.

A variety of normalization codes and references can be used to identify super duplex valves. Using American ASTM norms, if you are seeking a forged super duplex valve, you would ask for an A182 F53 or F55 valve; however, if you were seeking a cast super duplex valve, you would be looking for an A955 Gr. 5A or 6A valve or an A351 CD3MWCuN valve, previously known as an A890 Gr. 5A or 6A valve. According to German DIN norms, super duplex is recognized as 1.4501 and 1.4410.