About Duplex Steel — 2205, 32750 & 32760
Duplex stainless steels have a two-phase microstructure of roughly equal proportions of austenite and ferrite. This dual-phase structure provides approximately twice the 0.2% proof strength of standard austenitic steels (e.g. 304 or 316), making it possible to use thinner sections and achieve weight savings. The PREN (Pitting Resistance Equivalent Number) of 2205 is ≈ 35 and of super duplex 32750/32760 reaches ≈ 41–43, far exceeding standard 316L (PREN ≈ 23). Duplex is the industry standard for offshore topside piping, seawater cooling, and aggressive process streams.
Duplex Steel Sheets & Plates — 2205 · 32750 · 32760
Duplex Steel Sheets & Plates are supplied in hot-rolled, annealed and pickled (HRAP) condition conforming to ASTM A240. Solution annealing at 1050–1100°C followed by rapid quenching gives the correct phase balance and optimal corrosion resistance. All plates are supplied with heat-number traceable MTCs and PREN confirmation.
Sheet (CR)
1.0–6.0 mm
Plate (HR)
5–60 mm
Width × Length
Up to 2500 × 12,000 mm
| Grade | PREN | Thickness (mm) | Width (mm) | Condition |
|---|---|---|---|---|
| 2205 | ≥35 | 1.0–60 | Up to 2500 | HRAP / Annealed |
| 32750 (SAF 2507) | ≥43 | 1.5–50 | Up to 2000 | HRAP / Annealed |
| 32760 (Zeron 100) | ≥41 | 1.5–50 | Up to 2000 | HRAP / Annealed |
Standards
Duplex Steel Round Bar — 2205 · 32750 · 32760
Duplex Steel Round Bars are used for pump shafts, valve stems, fasteners, bolting, and machined structural components where the combination of high strength and corrosion resistance is required. 2205 is the standard choice; super duplex 32750 is specified for offshore and seawater applications requiring PREN ≥ 40.
Diameter
5 mm to 250 mm
Length
0.5 m to 6 m
Condition
Annealed
| Diameter (mm) | Grade | Condition | UTS (MPa) | PREN |
|---|---|---|---|---|
| 5–250 | 2205 | Annealed | 620 min | ≥35 |
| 5–200 | 32750 | Annealed | 795 min | ≥43 |
| 5–200 | 32760 | Annealed | 750 min | ≥41 |
Standards
Duplex Steel Seamless Pipes & Tubes — 2205 · 32750 · 32760
Duplex Steel Seamless Pipes are the preferred choice for offshore topside flowlines, injection lines, seawater lifting, and process piping where standard 316L would suffer SCC or pitting. Super duplex 32750 pipework is specified for the most aggressive offshore environments. All pipes are hydrotested and supplied with full NDE reports on request.
Pipe OD
21 mm to 323 mm
Schedules
SCH 5S to SCH XXS
Length
1 m to 6 m
| NB Size | OD (mm) | Grades | Schedules | Condition | Standard |
|---|---|---|---|---|---|
| ½″ – 1″ | 21.3 – 33.4 | 2205 / 32750 / 32760 | SCH 10S · 40S · 80S | Annealed | ASTM A790 |
| 1½″ – 3″ | 48.3 – 88.9 | 2205 / 32750 / 32760 | SCH 10S · 40S · 80S | Annealed | ASTM A790 |
| 4″ – 8″ | 114.3 – 219.1 | 2205 / 32750 / 32760 | SCH 5S · 10S · 40S · 80S | Annealed | ASTM A790 |
| 10″ – 12″ | 273.0 – 323.9 | 2205 / 32750 | SCH 5S · 10S · 40S | Annealed | ASTM A790 |
| 14″ – 24″ | 355.6 – 609.6 | 2205 | SCH 5S · 10S · 20S | Annealed | ASTM A790 |
Standards
Duplex Steel Flanges — 2205 · 32750 · 32760
Duplex Steel Flanges — forged to ASTM A182 F51 (2205) and F53/F55 (super duplex) — are stocked in all standard types for offshore, chemical, and seawater piping. Supplied with PREN confirmation and material traceability.
Types
WN · SO · BL · SW · TH · LJ
Sizes
½″–24″ NB
Pressure Class
150#–2500#
| Type | Material | Size Range | Pressure Class |
|---|---|---|---|
| Weld Neck / Slip-On / Blind | F51 (2205) | ½″–24″ | 150#–2500# |
| Weld Neck / Blind | F53 (32750) | ½″–24″ | 150#–2500# |
| All Types | F55 (32760) | ½″–24″ | 150#–2500# |
Standards
Duplex Steel Pipe Fittings — 2205 · 32750 · 32760
Duplex Steel Buttweld & Socket-Weld Fittings for offshore and chemical piping applications. Supplied to ASME B16.9 dimensions with ASTM A815 material conformance.
BW Fittings
½″–24″ NB
SW/Threaded
½″–4″ NB
Standards
ASME B16.9
| Fitting Type | Grade (UNS) | Size Range | Standard |
|---|---|---|---|
| Elbow 90° / 45° · Tee · Reducer · Cap | S31803/S32205 (2205) | ½″–24″ | ASTM A815 / ASME B16.9 |
| Elbow · Tee · Reducer | S32750 (32750) | ½″–24″ | ASTM A815 |
| All Fittings | S32760 (32760) | ½″–24″ | ASTM A815 |
Standards
Duplex Steel Square Bar & Flat Bar — 2205 · 32750 · 32760
Duplex Steel Square Bars & Flat Bars for structural supports, subsea frames, and machined components requiring the high strength of duplex in non-round cross-sections.
Square Bar
10×10 to 100×100 mm
Flat Bar
T:3–60 mm · W:10–200 mm
Condition
Annealed
| Section | Size Range | Grade | UTS (MPa) min | PREN | Condition |
|---|---|---|---|---|---|
| Square Bar | 10×10 to 100×100 mm | 2205 | 620 | ≥35 | Annealed |
| Square Bar | 10×10 to 80×80 mm | 32750 (SAF 2507) | 795 | ≥43 | Annealed |
| Square Bar | 10×10 to 60×60 mm | 32760 (Zeron 100) | 750 | ≥41 | Annealed |
| Flat Bar | 3–60 mm × 10–200 mm | 2205 / 32750 | 620 / 795 | ≥35 / ≥43 | Annealed |
| Flat Bar | 3–40 mm × 10–150 mm | 32760 (Zeron 100) | 750 | ≥41 | Annealed |
Standards
Duplex Steel Grade Reference — 2205 · 32750 · 32760
Chemical Composition — % by weight (max unless ranged)
| Grade | UNS | Cr | Ni | Mo | N | W / Cu | PREN | Type |
|---|---|---|---|---|---|---|---|---|
| 2205 | S31803 / S32205 | 21.0–23.0 | 4.5–6.5 | 2.5–3.5 | 0.08–0.20 | — | ≥35 | Standard Duplex |
| 32750 (SAF 2507) | S32750 | 24.0–26.0 | 6.0–8.0 | 3.0–5.0 | 0.24–0.32 | — | ≥43 | Super Duplex |
| 32760 (Zeron 100) | S32760 | 24.0–26.0 | 6.0–8.0 | 3.0–4.0 | 0.20–0.30 | W 0.5–1.0 / Cu 0.5–1.0 | ≥41 | Super Duplex |
Mechanical Properties — Annealed / Standard Condition
| Grade | UTS (MPa) min | 0.2% YS (MPa) min | Elong % min | Impact (J) at -46°C | Hardness HRC max |
|---|---|---|---|---|---|
| 2205 | 620 | 450 | 25 | >54 | 28 |
| 32750 | 795 | 550 | 15 | >45 | 32 |
| 32760 | 750 | 550 | 25 | >45 | 32 |
Grade Selection Guide
| Environment | Recommended Grade |
|---|---|
| Offshore topside piping, general seawater | 2205 |
| Aggressive seawater, high-chloride offshore | 32750 (SAF 2507) |
| Highly oxidising + reducing dual environments | 32760 (Zeron 100) |
| Pulp & paper digesters, kraft whitening | 2205 |
| Subsea umbilicals, injection flowlines | 32750 or 32760 |
Why Buy Duplex Steel from Suresh Metals?
Ready Stock — No Lead Times
All grades held in ready stock at our Mumbai facility. Same-day or next-day dispatch on standard sizes.
Mill Test Certificates (MTC)
Every consignment includes a heat-traceable MTC. NACE, PMI, third-party inspection on request.
Pan-India Delivery & Exports
Domestic delivery to any factory gate. Export to Middle East, SE Asia & Africa — sea-worthy packing, LC & TT accepted.
Cut-to-Size Processing
Plasma, waterjet, shearing, and sawing services — receive material sized to your drawing.
37+ Years of Expertise
Established 1987. Our team advises the right grade and form for your exact application.
Competitive Pricing
Direct mill sourcing and volume stock means best-in-market rates. Quote within 4 business hours.