Duplex 2205 Stainless Steel Seamless Pipe EN 10204-3.1 Certified

Parameters

• Chemical Composition (Typical, wt%):
  • Carbon (C) ≤ 0.03
  • Manganese (Mn) ≤ 2.00
  • Silicon (Si) ≤ 1.00
  • Chromium (Cr): 21.0 – 23.0
  • Nickel (Ni): 4.5 – 6.5
  • Molybdenum (Mo): 2.5 – 3.5
  • Nitrogen (N): 0.08 – 0.20
  • Phosphorus (P) ≤ 0.035
  • Sulfur (S) ≤ 0.020
• Mechanical Properties:
  • Tensile Strength (σb): ≥ 690 MPa
  • Yield Strength (σ0.2): ≥ 450 MPa
  • Elongation (δ): ≥ 25%
  • Hardness: ≤ 290 HB (Brinell)
• Physical Properties:
  • Density: 7.8 g/cm³
  • Melting Point: 1300 – 1390°C
  • Magnetic Property: Slightly magnetic (due to ferritic phase)

Performance

• Corrosion Resistance:
  • Excellent resistance to pitting, crevice corrosion, and general corrosion in chloride-containing environments (e.g., seawater, industrial effluents).
  • Pitting Resistance Equivalent Number (PREN) ≈ 34 – 36, outperforming 316L (PREN ≈ 32) and making it suitable for moderately aggressive chloride conditions.
  • Good tolerance to organic acids (acetic, lactic) and dilute inorganic acids (sulfuric acid with low chloride levels).
• Mechanical Performance:
  • High strength (1.5 – 2 times that of 304/316 austenitic stainless steels) while maintaining good ductility and toughness.
  • Superior resistance to stress corrosion cracking (SCC) compared to austenitic grades, especially in chloride-rich environments.

Key Features

• Duplex Microstructure: ~50% ferritic and ~50% austenitic phases, balancing the strength of ferritic steel and the corrosion resistance of austenitic steel.
• Weldability: Compatible with standard welding methods (TIG, MIG); minimal risk of sensitization, and post-weld heat treatment is rarely required.
• Cost Efficiency: Higher strength allows for thinner wall designs, reducing material usage and overall project costs.
• Temperature Stability: Performs well at both low (-40°C) and moderate high temperatures (up to 300°C), with no significant loss of toughness.

Similar Grades

• UNS S31803 (older designation, often interchangeable with 2205)
• UNS S32205 (updated version with tighter nitrogen control)
• SAF 2205 (Sandvik designation)
• F51 (ASTM designation for forgings)
• W.Nr. 1.4462 (DIN/EN standard)

Standards

• ASTM A312 / ASME SA-312: Seamless and welded austenitic and duplex stainless steel pipes for high-temperature service.
• ASTM A789 / ASME SA-789: Seamless and welded duplex stainless steel tubes for general corrosion service.
• ASTM A276: Stainless steel bars and shapes (includes 2205 for pipe billets).
• EN 10216-5: Seamless steel tubes for pressure purposes – Duplex stainless steels.
• JIS G3463: Duplex stainless steel pipes for general use.

Packaging

• Pipes are capped with plastic or metal end protectors to prevent damage to bevels/ends and contamination.
• Bundled with steel straps, wrapped in waterproof plastic film, and placed on wooden pallets or in fumigated wooden crates (for export) to ensure stability during transport.
• Custom packaging (e.g., anti-rust oil coating, labeled bundles with size/grade details) is available upon request.

Applications

• Oil & Gas Industry: Offshore platforms, subsea pipelines, and wellhead equipment (resistant to seawater and sour gas environments).
• Chemical Processing: Piping for handling chlorides, acids, and corrosive chemicals in reactors and transfer lines.
• Water Treatment: Desalination plants, wastewater treatment systems, and seawater intake/outlet pipes.
• Marine Engineering: Shipbuilding, coastal infrastructure, and ballast water systems.
• Construction: Structural pipes for bridges, tanks, and pressure vessels in harsh environments.