EN 1.4462 Duplex Stainless Steel Pipe Tube NB10 - NB400 Alloy Seamless Pipes for Oil and Gas

EN 1.4462 Duplex Stainless Steel Pipe Tube NB10 - NB400 Alloy Seamless Pipes for Oil and Gas

Products Specification

1. Introduction

EN 1.4462 (also known as X2CrNiMoN22-5-3, UNS S31803/S32205, or Duplex 2205) is a ferritic-austenitic stainless steel widely used in aggressive environments. Its dual-phase microstructure combines high strength (approximately twice that of standard austenitic steels like 316L) with exceptional corrosion resistance, especially in chloride-rich settings such as oil and gas extraction, seawater systems, and chemical processing. Seamless pipes in nominal bore (NB) sizes from NB10 (10 mm) to NB400 (400 mm) are critical for high-pressure applications in offshore platforms, pipelines, and heat exchangers.

2. Chemical Composition

The alloy’s corrosion resistance stems from its balanced composition, with chromium for passivation, molybdenum for pitting resistance, and nitrogen for strength stabilization:

Table 1: Chemical Composition (wt.%)

3. Mechanical Properties

1.4462 offers superior mechanical performance compared to standard austenitic grades, enabling thinner pipe walls and weight reduction:

Table 2: Mechanical Properties (Solution-Annealed)

4. Key Characteristics

• Corrosion Resistance: Excellent resistance to chloride-induced stress corrosion cracking (SCC), pitting, and crevice corrosion, outperforming 316L in seawater and H₂S environments.

• High Strength: Yield strength (~450 MPa) is ~2× higher than 316L, allowing reduced material use and cost savings.

• Weldability: Compatible with TIG, MIG, and SMAW using ER2209/ER2594 filler wires; post-weld heat treatment not required.

• Temperature Limits: Suitable for -50°C to 300°C; prolonged exposure >300°C may cause embrittlement.

• Magnetic Properties: Exhibits ferromagnetism due to its dual-phase structure.

5. Standards & Equivalent Grades

Manufacturing Standards:

• Pipe Production: EN 10216-5 (seamless pressure pipes).

• General Material: ASTM A789/A790 (seamless pipes), ASTM A182 F51 (fittings).

Equivalent Grades:

6. Applications in Oil & Gas

1.4462 seamless pipes are ideal for critical hydrocarbon and corrosive media transport:

• Offshore Platforms: Risers, subsea pipelines (NB100–NB400 sizes).

• Downhole Equipment: Casing tubes, wellhead components (NB10–NB50).

• Processing Units: Heat exchanger tubes, pressure vessels, and acid-resistant piping.

• Midstream Infrastructure: Gathering pipelines, LNG plant piping.

7. Export Packaging & Transportation

• Packaging:

  • Bundling: Pipes ≤159 mm OD, wrapped with waterproof material and steel straps.

  • Wooden Crates: For precision-finished pipes or small diameters (≤50 mm OD).

  • Surface Protection: Polished/annealed surfaces covered with plastic caps and anti-rust film.

• Transport:

  • Shipping Terms: FOB, CFR, CIF (sea freight for bulk orders)

  • Lead Time: ~35 days from order confirmation

  • Certifications: EN 10204 3.1, PED 2014/68/EU, and NACE MR0175 for sour service