Duplex Stainless Steel Pipe
At Stellanox Steel, we manufacture and supply high-performance Duplex Stainless Steel Pipes designed for use in critical, high-pressure, and highly corrosive environments. Combining excellent mechanical strength with superior corrosion resistance, our duplex pipes are trusted across industries like oil & gas, chemical processing, marine engineering, offshore drilling, and desalination projects worldwide.
Built to meet international standards and customized to your project needs, Stellanox Steel’s duplex pipes offer a cost-effective, durable solution for aggressive service conditions.
What are Duplex Stainless Steel Pipes?
Duplex Stainless Steel Pipes are tubular products made from duplex-grade alloys, featuring an even mix of austenitic and ferritic microstructures.
This unique structure offers twice the yield strength of conventional austenitic stainless steels (like 304/316) along with excellent resistance to pitting, crevice corrosion, and chloride-induced stress corrosion cracking.
These properties make duplex pipes highly sought after for transporting fluids, gases, and corrosive chemicals under high pressure and extreme temperatures — particularly in marine, offshore, and chemical plant environments.
| Products |
|---|
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Stainless Steel |
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Carbon Steel |
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Duplex Stainless Steel |
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Super Duplex Stainless Steel |
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Alloy Steel |
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Titanium |
|
Hastelloy |
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Inconel |
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Monel |
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Aluminium |
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Copper |
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Pure Nickel |
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Flanges |
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Forged Fittings |
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Valves |
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Fasteners |
Key Features
- Superior Strength: 2X the yield strength of 300-series stainless steels.
- Outstanding Corrosion Resistance: Excellent protection against pitting, crevice, and stress corrosion.
- Excellent Weldability: Lower risk of weld cracking and distortion compared to ferritic grades.
- High Resistance to Fatigue and Impact Loads: Suitable for dynamic, cyclic load environments.
- Reduced Wall Thickness Possible: Savings on material cost and weight.
- Good Toughness at Sub-Zero Temperatures: Suitable for Arctic, subsea, and cryogenic applications.
Grades
Specifications
| Property | Details |
|---|---|
|
Product
|
Duplex Stainless Steel Pipe
|
|
Common Grades |
UNS S31803 (2205), UNS S32205, UNS S32750 (Super Duplex 2507), UNS S32760
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Manufacturing Standards
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ASTM A790 (Seamless & Welded), ASTM A928 (Welded SAW Pipes), EN 10216-5, EN 10217-7
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Pipe Types
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Seamless (SMLS), Welded (ERW, HFW, LSAW, SSAW)
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Size Range (Seamless)
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1/8” NB to 24” NB (10.3 mm to 610 mm OD)
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Size Range (Welded)
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1/2” NB to 48” NB (21.3 mm to 1219 mm OD)
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Wall Thickness
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SCH 5S, 10S, 40S, 80S, 160S, XXS
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Length Options
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Single Random (5–7 m), Double Random (11–13 m), Custom Lengths
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Surface Finish Options
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Pickled & Passivated, Polished, Annealed, Bead Blasted
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End Types
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Plain End (PE), Beveled End (BE), Threaded End (TE)
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Testing and Certification
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Hydrostatic Test, Ultrasonic Test, PMI Test, EN 10204 3.1/3.2, NACE MR0175 Certification
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Chemical Composition
| Element | Composition (%) |
|---|---|
|
Carbon (C) |
≤ 0.030
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Chromium
Cr |
21.0 – 23.0
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Nickel
Ni
|
4.5 – 6.5
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Molybdenum
Mo
|
2.5 – 3.5
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Nitrogen
N
|
0.08 – 0.20
|
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Manganese
Mn
|
≤ 2.0
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Silicon
Si
|
≤ 1.0
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Phosphorus
P
|
≤ 0.030
|
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Sulfur
S
|
≤ 0.020
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Iron
Fe
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Balance |
Mechanical Properties
| Property | Value |
|---|---|
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Tensile Strength (MPa)
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≥ 620
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Yield Strength 0.2% Proof (MPa)
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≥ 450
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Elongation (%)
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≥ 25
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Hardness (Brinell HB)
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≤ 290
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Impact Energy (Charpy V-notch)
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≥ 100 Joules @ -46°C
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Equivalent Grades
| Standard | Equivalent Grade |
|---|---|
|
ASTM |
A240 (Plate/Sheet), A790 (Pipe)
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UNS
|
S31803 (2205), S32205 (2205 improved)
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EN
|
1.4462
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DIN
|
X2CrNiMoN22-5-3
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JIS
|
SUS 329J3L
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Weight Chart (kg/m²)
| Size (inches) | OD (mm) | WT (mm) | Weight per Meter (kg) |
|---|---|---|---|
|
1″
|
33.4
|
3.38
|
2.38
|
|
1.5″
|
48.3
|
3.68
|
4.21
|
|
2″
|
60.3
|
3.91
|
5.76
|
|
3″
|
88.9
|
5.49
|
10.91
|
|
4″
|
114.3
|
6.02
|
16.46
|
|
6″
|
168.3
|
7.11
|
30.69
|
|
8″
|
219.1
|
8.18
|
48.31
|
Applications in Various Industries
Stellanox Steel’s products are valued for their strength, machinability, and cost-effectiveness across multiple sectors:
Benefits
- Exceptional Strength: Allows thinner-walled piping, reducing overall weight and material cost.
- High Corrosion Resistance: Protects against pitting, crevice corrosion, and stress corrosion cracking.
- Outstanding Mechanical and Fatigue Strength: Reliable under dynamic loads and thermal cycling.
- Good Weldability: Suitable for field welding without extensive post-weld treatments.
- Long-Term Service Life: Resistant to erosion, corrosion, and wear.
- Eco-Friendly Material: Fully recyclable, contributing to green energy and sustainable infrastructure.
Frequently Asked Questions
Super Duplex 2507 pipes (UNS S32750) have higher strength and corrosion resistance compared to standard Duplex 2205, and are used in extremely aggressive environments like deep-sea oilfields.
Yes. With proper procedures, duplex pipes can be welded efficiently and maintain excellent corrosion resistance even in highly corrosive offshore conditions.
Yes, grades compliant with NACE MR0175/ISO 15156 are suitable for sour (H₂S-containing) environments.
We offer pickled and passivated, polished, bead-blasted, and custom surface treatments depending on application needs.
2025 Stellanox Steel |