Duplex and Super Duplex Steel Supplier in Chennai
Nobel Weld is a duplex and super duplex steel supplier in Chennai for UNS S31803 and S32205 (2205), S32750 (2507), S32760 and S32550 (Ferralium 255). We supply plate, bar, pipe and fittings, and machine duplex impellers, shafts, sleeves and fasteners.
Duplex steels combine austenite and ferrite, which roughly doubles the yield strength of 316L and gives far better resistance to chloride stress-corrosion cracking and pitting.
What are duplex and super duplex stainless steels?
Duplex stainless steels have a two-phase microstructure of about half austenite and half ferrite. They carry around 22% chromium, 3% molybdenum and nitrogen; super duplex grades raise chromium to 25% and molybdenum to 3.5–4%, for a pitting resistance equivalent (PREN) above 40.
The result is high strength, good toughness and resistance to seawater and chlorides at a lower nickel content than austenitic alloys, so they are often cheaper than 6Mo or nickel alloys for the same duty.
- Grades
- UNS S31803/S32205, S32750/S32760, S32550
- Forms
- Plate, bar, pipe, fittings
- Typical service
- Chloride stress-corrosion, seawater
- Certificates
- EN 10204 3.1; 3.2 and PMI on request
Duplex and super duplex grades we supply
| Grade | UNS / designation | Typical use |
|---|---|---|
| Duplex 2205 | S31803 / S32205 | General chloride service, PREN about 35 |
| Super duplex 2507 | S32750 | Seawater and offshore, PREN 41 min |
| Super duplex (Zeron 100 type) | S32760 | Seawater with Cu and W additions, PREN 40 min |
| Ferralium 255 | S32550 / SA182 F61 | Cu-bearing super duplex for pumps and valves |
Forms and standards
- Plate and sheet (ASTM A240 / ASME SA240)
- Bar (ASTM A276, A479)
- Seamless and welded pipe (ASTM A790, A928)
- Forgings and flanges (ASTM A182 F51, F53, F55, F61)
- Fittings (ASTM A815)
Pump and valve parts from a duplex and super duplex steel supplier in Chennai
Impellers, casing rings, shafts, sleeves and bushes for seawater and process pumps are machined from duplex and super duplex bar and forgings. Welding uses ER2209 or ER2594 with controlled heat input to keep the phase balance right.
Duplex and super duplex chemical composition
| Grade (UNS) | Cr | Ni | Mo | N | Other |
|---|---|---|---|---|---|
| 2205 (S32205) | 22.0–23.0 | 4.5–6.5 | 3.0–3.5 | 0.14–0.20 | – |
| 2507 (S32750) | 24.0–26.0 | 6.0–8.0 | 3.0–5.0 | 0.24–0.32 | Cu 0.5 max |
| S32760 | 24.0–26.0 | 6.0–8.0 | 3.0–4.0 | 0.20–0.30 | Cu 0.5–1.0, W 0.5–1.0 |
| Ferralium 255 (S32550) | 24.0–27.0 | 4.5–6.5 | 2.9–3.9 | 0.10–0.25 | Cu 1.5–2.5 |
Duplex and super duplex mechanical properties
| Grade | Tensile, MPa | Yield (0.2%), MPa | Elongation, % |
|---|---|---|---|
| 2205 (S32205) | 655 | 450 | 25 |
| 2507 (S32750) | 795 | 550 | 15 |
| S32760 | 750 | 550 | 25 |
| Ferralium 255 (S32550) | 760 | 550 | 15 |
Welding filler wire for duplex and super duplex
| Alloy family | Standard | Classifications | For base metal |
|---|---|---|---|
| Duplex and super duplex | AWS A5.9 | ER2209, ER2594 | UNS S31803 / S32205, S32750 / S32760 |
TIG rods and MIG spools with 3.1 certificates per heat. See the full filler wire range.
Where duplex and super duplex is used
- Seawater pumps, valves and firewater systems
- Offshore and desalination piping
- Chemical tankers and process vessels
- Pulp and paper digesters and bleach plants
Duplex and super duplex parts we machine
Where we deliver
Duplex and super duplex for Chennai, Tamil Nadu and India
From Chennai, we serve plants, OEMs and EPC contractors across Tamil Nadu and the rest of India, with EN 10204 3.1 certificates, heat-number traceability and export packing where needed.
- Chennai
- From our shop in Gowrivakkam to plants in Manali, Ennore, Ambattur, Guindy, Sriperumbudur and Oragadam.
- Tamil Nadu
- Coimbatore, Hosur, Tiruchirappalli, Thoothukudi, Cuddalore, Ranipet, Madurai and Mettur.
- India
- Gujarat, Maharashtra, Karnataka, Telangana, Andhra Pradesh and Kerala; export on ex-works, FOB or CIF terms.
FAQ
Duplex and super duplex: common questions
Which grades does your duplex and super duplex steel supply in Chennai cover?
UNS S31803/S32205 (2205), S32750 (2507), S32760 and S32550 (Ferralium 255) in plate, bar, pipe, forgings and machined parts.
What is the difference between duplex and super duplex?
Super duplex has more chromium, molybdenum and nitrogen, giving a PREN above 40 against about 35 for 2205. It is used for seawater and harsher chloride service.
Which filler wire is used for super duplex?
ER2594 to AWS A5.9 for super duplex, and ER2209 for 2205 duplex. We supply both.
Send your duplex and super duplex enquiry
Share the grade, form, size and quantity, or your drawing. You get a technical and commercial reply within 48 hours.