What is UNS S32205 Duplex Steel Tube?
UNS S32205 is a Duplex 2205 stainless steel tube, known for its high yield strength, excellent corrosion resistance (especially to pitting, crevice, and stress corrosion cracking), and good fatigue strength. Its unique two-phase (ferritic-austenitic) metallurgical structure allows it to be used in high-pressure and highly corrosive environments. It is widely used in the oil and gas, chemical processing, and marine industries.
What is UNS S32750 Seamless Tube?
UNS S32750 seamless tube is a super duplex stainless steel pipe known for high strength and superior corrosion resistance, particularly in high chloride environments. It is a reliable choice for demanding applications like offshore oil and gas, chemical processing, and marine uses, where its balanced microstructure provides resistance to cracking and pitting.
What is the difference between S32750 and S32205?
The main difference is that S32750 (Super Duplex) offers significantly higher corrosion resistance and strength than S32205 (Duplex stainless steel) due to its higher alloying content of chromium, molybdenum, and nitrogen, making it suitable for more aggressive, high-chloride environments like warm seawater and acidic media, while S32205 is for moderately corrosive conditions.
Standards
| Property | UNS S32205 (Duplex 2205) | UNS S32750 (Super Duplex 2507) |
|---|---|---|
| Standard | ASTM A789 / A790 / A928 | ASTM A789 / A790 / A928 |
| Type | Duplex Stainless Steel | Super Duplex Stainless Steel |
| Common Name | Duplex 2205 | Super Duplex 2507 |
| UNS Number | S32205 / S31803 | S32750 |
| EN Grade | 1.4462 | 1.4410 |
| Manufacturing Process | Seamless / Welded Tube | Seamless / Welded Tube |
UNS S32205 Duplex Steel Tube vs.UNS S32750 Specification
| Specification | S32205 Duplex Tube | S32750 Super Duplex Tube |
|---|---|---|
| Outer Diameter | 6mm – 630mm | 6mm – 630mm |
| Wall Thickness | 0.5mm – 50mm | 0.5mm – 50mm |
| Length | Up to 12m or custom | Up to 12m or custom |
| Surface Finish | Pickled, polished, bright | Pickled, polished, bright |
| Tolerance | ASTM A789 / A790 | ASTM A789 / A790 |
| Delivery Condition | Annealed / Solution treated | Annealed / Solution treated |
| Certification | EN 10204 3.1 / 3.2 | EN 10204 3.1 / 3.2 |
Chemical Composition Comparison
| Element | S32205 (2205) | S32750 (2507) |
|---|---|---|
| Chromium (Cr) | 21.0 – 23.0% | 24.0 – 26.0% |
| Nickel (Ni) | 4.5 – 6.5% | 6.0 – 8.0% |
| Molybdenum (Mo) | 2.5 – 3.5% | 3.0 – 5.0% |
| Nitrogen (N) | 0.08 – 0.20% | 0.24 – 0.32% |
| Manganese (Mn) | ≤ 2.0% | ≤ 1.2% |
| Carbon (C) | ≤ 0.03% | ≤ 0.03% |
| Silicon (Si) | ≤ 1.0% | ≤ 0.8% |
| Iron (Fe) | Balance | Balance |
Mechanical Properties
| Property | S32205 | S32750 |
|---|---|---|
| Tensile Strength (MPa) | 620 – 880 | 800 – 1000 |
| Yield Strength (MPa) | ≥ 450 | ≥ 550 |
| Elongation (%) | ≥ 25 | ≥ 25 |
| Hardness (HB) | ≤ 290 | ≤ 310 |
| Density (g/cm³) | 7.8 | 7.8 |
Corrosion Resistance
| Type of Corrosion | S32205 (Duplex 2205) | S32750 (Super Duplex 2507) |
|---|---|---|
| Pitting Resistance (PREN) | ~35 | ≥ 42 |
| Chloride SCC Resistance | Excellent | Superior |
| General Corrosion | Very Good | Excellent |
| Crevice Corrosion | Very Good | Excellent |
| Acid Resistance | Moderate | High (suitable for H₂SO₄ and chlorides) |
Applications
| S32205 Duplex Tube | S32750 Super Duplex Tube |
|---|---|
| Heat exchangers | Offshore oil & gas equipment |
| Pressure vessels | Subsea pipelines |
| Marine exhaust systems | Desalination plants |
| Chemical processing | Paper and pulp digesters |
| Water treatment | Heat exchangers in seawater environments |
Why Choose Gnee?
GNEE has over 18 years of experience exporting duplex and super duplex steel. Our ISO, SGS, and BV-certified production facilities offer a comprehensive inventory of S32205 and S32750 steel tubes (sizes from 6mm to 630mm). We offer custom fabrication including cutting, polishing, bending, and welding. We offer competitive factory pricing and carry a mill test certificate (MTC EN 10204 3.1). We ship worldwide in moisture- and rust-resistant packaging.
Packaging and Delivery
| Item | Details |
|---|---|
| Package | Standard export seaworthy package with waterproof paper, plastic caps, and wooden cases |
| Loading Port | Tianjin, Qingdao, or Shanghai |
| Container Capacity | 1×20ft: Max 25 Tons, Max 5.8m 1×40ft: Max 25 Tons, Max 11.8m |
| Delivery Time | 7–15 working days depending on order quantity |
| Shipping Options | By sea, air, or express (DHL, FedEx, TNT) |
