Super Duplex Steel Pipes
Super Duplex Steel Pipes are high-performance stainless steel pipes known for their exceptional strength, corrosion resistance, and durability. These pipes combine the best properties of austenitic and ferritic stainless steels, offering superior resistance to chloride stress corrosion cracking, pitting, and crevice corrosion, especially in aggressive environments such as seawater and chemical processing industries. They are widely used in oil & gas, petrochemical, desalination plants, and marine applications where high strength and corrosion resistance are critical. Super Duplex pipes typically conform to standards such as ASTM A789 and UNS S32750, featuring high chromium (25-28%), molybdenum (3-5%), and nitrogen content, which enhance their performance in harsh conditions.
Super Duplex Steel Pipes - Specifications
| Parameter | Description / Options |
|---|---|
| Standards | ASTM A789, ASTM A790, ASTM A213, ASTM A269, EN 10216-5, UNS S32750, UNS S32760 |
| Grades | UNS S32750, UNS S32760 (Super Duplex grades) |
| Type | Seamless (SMLS), Welded (ERW), Hot Finished |
| Outside Diameter (OD) | 6 mm to 610 mm (1/4" to 24") |
| Wall Thickness | Schedule 5, 10, 40, 80, 160 (per ASME B36.19M or customer requirements) |
| Length | Random length (5-7 m), Fixed length (up to 12 m), Customized lengths available |
| End Type | Plain End (PE), Beveled End (BE), Threaded |
| Surface Finish | Mill Finish, Pickled & Passivated, Electro-Polished |
| Testing | Hydrostatic Test, Eddy Current Test, Ultrasonic Test (UT), PMI Test |
| Certification | EN 10204 3.1 / 3.2 Mill Test Certificate |
| Applications | Oil & Gas, Chemical Processing, Marine, Desalination, Power Plants |
Mechanical Properties
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HB) |
|---|---|---|---|---|
| UNS S32750 | 830 - 930 | 550 - 700 | 25 - 35 | 250 - 300 |
| UNS S32760 | 860 - 960 | 600 - 750 | 20 - 30 | 280 - 320 |
Chemical Composition
| Element | UNS S32750 (%) | UNS S32760 (%) |
|---|---|---|
| Carbon (C) | ≤ 0.03 | ≤ 0.03 |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 |
| Silicon (Si) | ≤ 0.80 | ≤ 0.80 |
| Phosphorus (P) | ≤ 0.030 | ≤ 0.030 |
| Sulfur (S) | ≤ 0.020 | ≤ 0.020 |
| Chromium (Cr) | 24.0 - 26.0 | 25.0 - 27.0 |
| Nickel (Ni) | 6.0 - 8.0 | 6.0 - 8.0 |
| Molybdenum (Mo) | 3.0 - 5.0 | 3.0 - 5.5 |
| Nitrogen (N) | 0.20 - 0.30 | 0.24 - 0.32 |
| Copper (Cu) | ≤ 0.50 | ≤ 0.50 |