Duplex Stainless Steel Pipe
- Duplex stainless steel pipe features a balanced austenitic-ferritic microstructure, offering nearly double the yield strength of standard 300-series austenitic grades. It exhibits outstanding resistance to chloride stress corrosion cracking (SCC) and pitting, with excellent weldability and formability. Widely used in marine environments, chemical processing, and oil & gas extraction, this product ensures long-term durability and reliability in high-pressure, high-temperature, and highly corrosive conditions. Its superior mechanical properties allow for reduced wall thickness, offering significant weight and cost savings compared to conventional steel pipes.
Application：
Duplex stainless steel pipes are essential components in industries where corrosion resistance and mechanical strength are critical. The primary application lies in the Oil & Gas sector, where they are used for subsea pipelines, flowlines, process piping, and heat exchanger tubes, often handling aggressive fluids containing chlorides, H₂S, and CO₂. Their resistance to sulfide stress corrosion cracking makes them suitable for sour service environments.
In Chemical and Petrochemical processing, these pipes transport corrosive media such as acids and alkalis, particularly in urea production, pulp & paper bleaching, and distillation columns. The Marine and Shipbuilding industry relies on them for seawater cooling systems, desalination plants, and ballast water treatment, given their superior resistance to pitting and crevice corrosion in saline conditions.
Beyond these, the Power Generation sector uses them in flue gas desulfurization (FGD) units and condenser tubing where thermal fatigue and corrosion resistance are paramount. In the Pulp & Paper industry, they are vital for handling highly corrosive chloride-laden bleaching liquors. Furthermore, these pipes are found in construction and architecture where structural integrity and aesthetic longevity are required, as well as in the Food and Beverage industry for specific high-heat sanitation processes.
Utilizing duplex stainless pipes allows engineers to design lighter support structures due to high strength, reduce installation costs through thinner wall sections, and ensure extended service life with minimal maintenance, thereby lowering the total lifecycle cost in demanding operational scenarios.
Specification:
| SPECIFICATION STANDARD(STEEL PIPE) | |||||||||||||||||||
| Normal Diameter | OD(MM) | WALL THICKMESS(MM) | |||||||||||||||||
| ANSI B36.10M | ANSI B36.19M | ||||||||||||||||||
| A(MM) | B(INCH) | ASME | SCH5/5S | SCH10S | SCH10 | SCH20 | SCH30 | STD | SCH40 | SCH40S | SCH60 | XS | SCH80 | SCH80S | SCH100 | SCH120 | SCH140 | SCH160 | XXS |
| 6 | 1/8" | 10.29 | 1.24 | 1.24 | 1.45 | 1.73 | 1.73 | 1.73 | 2.41 | 2.41 | 2.41 | ||||||||
| 8 | 1/4" | 13.72 | 1.65 | 1.65 | 1.85 | 2.24 | 2.24 | 2.24 | 3.02 | 3.02 | 3.02 | ||||||||
| 10 | 3/8" | 17.14 | 1.65 | 1.65 | 1.85 | 2.31 | 2.31 | 2.31 | 3.2 | 3.2 | 3.2 | ||||||||
| 15 | 1/2" | 21.34 | 1.65 | 2.11 | 2.11 | 2.41 | 2.77 | 2.77 | 2.77 | 3.73 | 3.73 | 3.73 | 4.78 | 7.47 | |||||
| 20 | 3/4" | 26.67 | 1.65 | 2.11 | 2.11 | 2.41 | 2.87 | 2.87 | 2.87 | 3.91 | 3.91 | 3.91 | 5.56 | 7.82 | |||||
| 25 | 1" | 33.40 | 1.65 | 2.77 | 2.77 | 2.9 | 3.38 | 3.38 | 3.38 | 4.55 | 4.55 | 4.55 | 6.35 | 9.09 | |||||
| 32 | 1.1/4" | 42.16 | 1.65 | 2.77 | 2.77 | 2.97 | 3.56 | 3.56 | 3.56 | 4.85 | 4.85 | 4.85 | 6.35 | 9.7 | |||||
| 40 | 1.1/2" | 48.26 | 1.65 | 2.77 | 2.77 | 3.18 | 3.68 | 3.68 | 3.68 | 5.08 | 5.08 | 5.08 | 7.14 | 10.15 | |||||
| 50 | 2" | 60.32 | 1.65 | 2.77 | 2.77 | 3.18 | 3.91 | 3.91 | 3.91 | 5.54 | 5.54 | 5.54 | 8.74 | 11.07 | |||||
| 65 | 2.1/2" | 73.02 | 2.11 | 3.05 | 3.05 | 4.78 | 5.16 | 5.16 | 5.16 | 7.01 | 7.01 | 7.01 | 9.53 | 14.02 | |||||
| 80 | 3" | 88.90 | 2.11 | 3.05 | 3.05 | 4.78 | 5.49 | 5.49 | 5.49 | 7.62 | 7.62 | 7.62 | 11.13 | 15.25 | |||||
| 90 | 3.1/2" | 101.60 | 2.11 | 3.05 | 3.05 | 4.78 | 5.74 | 5.74 | 5.74 | 8.08 | 8.08 | 8.08 | |||||||
| 100 | 4" | 114.30 | 2.11 | 3.05 | 3.05 | 4.78 | 6.02 | 6.02 | 6.02 | 8.56 | 8.56 | 8.56 | 11.13 | 13.49 | 17.12 | ||||
| 125 | 5" | 141.30 | 2.77 | 3.40 | 3.40 | 6.55 | 6.55 | 6.55 | 9.53 | 9.53 | 9.53 | 12.7 | 15.88 | 19.05 | |||||
| 150 | 6" | 168.28 | 2.77 | 3.40 | 3.40 | 7.11 | 7.11 | 7.11 | 10.97 | 10.97 | 10.97 | 14.27 | 18.26 | 21.95 | |||||
| 200 | 8" | 219.08 | 2.77 | 3.76 | 3.76 | 6.35 | 7.04 | 8.18 | 8.18 | 8.18 | 10.31 | 12.7 | 12.7 | 12.7 | 15.09 | 18.26 | 20.62 | 23.01 | 22.23 |
| 250 | 10" | 273.05 | 3.40 | 4.19 | 4.19 | 6.35 | 7.8 | 9.27 | 9.27 | 9.27 | 12.7 | 12.7 | 15.09 | 12.7 | 18.26 | 21.44 | 25.4 | 28.58 | 25.4 |
| 300 | 12" | 323.85 | 3.96 | 4.57 | 4.57 | 6.35 | 8.38 | 9.53 | 10.31 | 9.53 | 14.27 | 12.7 | 17.48 | 12.7 | 21.44 | 25.4 | 28.58 | 33.32 | 25.4 |
| 350 | 14" | 355.60 | 3.96 | 4.78 | 6.35 | 7.92 | 9.53 | 9.53 | 11.13 | 9.53 | 15.09 | 12.7 | 19.05 | 12.7 | 23.83 | 27.79 | 31.75 | 35.71 | |
| 400 | 16" | 406.40 | 4.19 | 4.78 | 6.35 | 7.92 | 9.53 | 9.53 | 12.7 | 9.53 | 16.66 | 12.7 | 21.44 | 12.7 | 26.19 | 30.96 | 36.53 | 40.49 | |
| 450 | 18" | 457.20 | 4.19 | 4.78 | 6.35 | 7.92 | 11.13 | 9.53 | 14.27 | 9.53 | 19.05 | 12.7 | 23.83 | 12.7 | 29.36 | 34.93 | 39.67 | 45.24 | |
| 500 | 20" | 508.00 | 4.78 | 5.54 | 6.35 | 9.53 | 12.7 | 9.53 | 15.09 | 9.53 | 20.62 | 12.7 | 26.19 | 12.7 | 32.54 | 38.1 | 44.45 | 50.01 | |
| 550 | 22" | 558.80 | 4.78 | 5.54 | 6.35 | 9.53 | 12.7 | 9.53 | 22.23 | 12.7 | 28.58 | 34.93 | 41.28 | 47.63 | 53.98 | ||||
| 600 | 24" | 609.60 | 5.54 | 6.35 | 6.35 | 9.53 | 14.27 | 9.53 | 17.48 | 9.53 | 24.61 | 12.7 | 30.96 | 12.7 | 38.89 | 46.02 | 52.37 | 59.54 | |
| 650 | 26" | 660.40 | 7.92 | 12.7 | 9.53 | 12.7 | |||||||||||||
| 700 | 28" | 711.20 | 7.92 | 12.7 | 15.88 | 9.53 | 12.7 | ||||||||||||
| 750 | 30" | 762.00 | 6.35 | 7.92 | 12.7 | 15.88 | 9.53 | 12.7 | |||||||||||
| 800 | 32" | 812.00 | 7.92 | 12.7 | 15.88 | 9.53 | 17.48 | 12.7 | |||||||||||
| 850 | 34" | 863.60 | 7.92 | 12.7 | 15.88 | 9.53 | 17.48 | 12.7 | |||||||||||
| 900 | 36" | 914.40 | 7.92 | 12.7 | 15.88 | 9.53 | 19.05 | 12.7 | |||||||||||
Standard：
| Classification | Main Products | Chemical Composition (Typical %) | Mechanical Properties (Typical) |
| Lean Duplex | Welded & Seamless Pipes, Fittings | Cr: 21-22%, Ni: 1.5-2.5%, Mo: 0.1-0.3%, N: 0.2-0.25% | Yield Strength: ≥ 450 MPa Tensile: ≥ 650 MPa Elongation: ≥ 25% |
| Standard Duplex | Seamless Pipes, ERW Pipes, Hollow Bars | Cr: 22-23%, Ni: 4.5-6.5%, Mo: 2.5-3.5%, N: 0.14-0.2% | Yield Strength: ≥ 485 MPa Tensile: ≥ 690 MPa Elongation: ≥ 25% Hardness: ≤ 290 HB |
| Super Duplex | Heavy Wall Seamless Pipes, Coils | Cr: 24-26%, Ni: 6-8%, Mo: 3-5%, N: 0.24-0.32%, W/Cu (optional) | Yield Strength: ≥ 550 MPa Tensile: ≥ 800 MPa Elongation: ≥ 25% PREN > 40 |
Process：
Packing:
