Duplex stainless steel combines the beneficial properties of austenitic and ferritic stainless steels, featuring a dual-phase microstructure of approximately equal parts austenite and ferrite. This unique composition gives duplex stainless steels enhanced strength, improved corrosion resistance, and better stress corrosion cracking resistance compared to standard austenitic stainless steels.

Duplex flanges with welded ends and seamless construction ensures leak-proof connections and are widely used across various industries due to their excellent corrosion resistance, high strength, durability, and for their reliability and longevity in demanding environments.

SPFA stock a core range of common standards and sizes, many of which are certified to multiple dimension and material specifications when the standards overlap. Many of the larger sizes are stocked in a semi-finished very heavy wall and are machined according to the required finished size, face and weld prep.

Commonly “Duplex” is referred to as the proprietary grade 2205, however the conventional grades F51 and F60 are more accurate. Most flange material is produced as dual grade F51/F60.