Super Duplex Stainless Steel Flanges Supplier in Mumbai, India
Nicorex Alloys is an ISO 9001 and ISO 14001 certified stockist and supplier of super duplex steel flanges in Mumbai, India. We stock Super Duplex 2507 (F53) and S32760 (F55) in weld neck, blind, slip-on, socket weld, threaded, and RTJ types made according to the ASTM A182 / ASME SA182 standard. Sizes range from 1/2″ NB to 48″ NB in pressure classes 150# to 2500#. All shipments carry EN 10204/3.1 mill test certificates.
Super duplex steel flanges are forged piping components with a PREN of 40 or higher. They have a near-equal (50/50) austenite-ferrite microstructure with approximately 25% chromium, 7% nickel, and 4% molybdenum. This gives them high strength and corrosion resistance in the duplex family. Offshore oil and gas, desalination, chemical processing, and marine industries use these flanges.
Super Duplex Steel Flanges Specifications
| Specifications | ASTM A182 / ASME SA182 |
|---|---|
| Standards | ANSI/ASME B16.5, B16.47 Series A & B, MSS SP-44, EN-1092, DIN, JIS |
| Grades | F53 (UNS S32750, 1.4410); F55 (UNS S32760, 1.4501) |
| Pressure Classes | 150#, 300#, 600#, 900#, 1500#, 2500# |
| Size Range | 1/2″ NB to 48″ NB (DN15 to DN1200) |
| Face Types | RF, FF, RTJ, LJF, Tongue & Groove, Male-Female |
| Flange Types | Weld Neck, Slip-On, Blind, Socket Weld, Threaded, Lap Joint, Long Weld Neck, Spectacle Blind, Orifice, RTJ, Reducing |
What are Super Duplex Steel Flanges?
Super duplex steel flanges are forged connection components made as per ASTM A182. They form leak-proof bolted joints in piping exposed to aggressive chloride environments. A PREN of 40 or higher comes from around 25% chromium, 4% molybdenum, and elevated nitrogen. Key traits include a CPT above 50°C, minimum yield strength of 550 MPa, and NACE MR0175/ISO 15156 compliance for sour gas service.
Flanges are forged at 1025 to 1230°C and solution annealed at 1025 to 1125°C with rapid water quench. Service range is -50°C to +250°C. Above 300°C, sigma phase forms and reduces toughness. Compared to duplex 2205, super duplex offers 22% higher yield and better pitting resistance (PREN 42 vs 35).
Types of Super Duplex Steel Flanges
Super Duplex Steel Weld Neck Flange (WNRF)
Super Duplex Stainless Steel Blind Flange (BLRF)
Super Duplex Steel Slip-On Flange
Super Duplex Socket Weld Flange
Super Duplex SS Threaded Flange
Super Duplex Lap Joint Flange
SDSS Spectacle Blind Flange
Super Duplex Steel Orifice Flange
Super Duplex Ring Type Joint Flange (RTJ)
Super Duplex Long Weld Neck Flange
Super Duplex Reducing Flange
Get Super Duplex Steel Flanges at Competitive Prices
Available Grades of Super Duplex Steel Flanges
Super Duplex UNS S32750 Flange
This is the most widely used super duplex grade. Its 25Cr-7Ni-4Mo-N composition gives a PREN of 41-43 with 550 MPa yield and 800 MPa tensile strength. CPT exceeds 50°C. NACE MR0175 compliant.
Super Duplex UNS S32760 Flange
F55 (S32760) has tungsten and copper in its chemistry, which S32750 does not. This gives it a PREN above 40 and better resistance to crevice corrosion in stagnant seawater. It is widely used in North Sea offshore projects for this reason.
Industries and Applications of Super Duplex Steel Flanges
- Offshore Oil & Gas: Subsea manifold flanges, Xmas tree connections, and riser piping joints.
- Desalination & Water Treatment: RO pump flanges, brine handling, and seawater intake piping use SDS flanges.
- Chemical & Petrochemical: Reactor vessel flanges, heat exchangers, and FGD scrubber flanges.
- Marine & Shipbuilding: Seawater cooling flanges, ballast piping, and fire main joints.
- Pulp, Paper & Power Generation: Bleach plant flanges, cooling water joints, and condenser piping.
Frequently Asked Questions
What is the Difference Between Super Duplex and Standard Duplex Flanges?
Which ASTM Standard Covers Super Duplex Flanges?
What is the Maximum Service Temperature for Super Duplex Flanges?
What Welding Filler Metals Are Used for Super Duplex Flanges?
Use ER2594 filler wire per AWS A5.9 for GTAW and GMAW. For SMAW, use E2594 electrodes. Keep heat input between 0.5 and 2.5 kJ/mm with interpass temperature below 150°C.