High Strength 329 Duplex Stainless Steel Pipe S32900 Tubing For High Pressure Marine

High Strength 329 Duplex Stainless Steel Pipe S32900 Tubing for High Pressure and Marine Applications

Products Specification

Product: 329 Stainless Steel Tubing / Pipe

Material Grade: UNS S32900, EN 1.4460

Overview:
329 stainless steel tubing is a high-performance duplex (austenitic-ferritic) stainless steel alloy. It offers an exceptional combination of high strength, excellent corrosion resistance (particularly to stress corrosion cracking and pitting), and good weldability. This makes it ideal for demanding applications in aggressive environments.

Key Features & Benefits:

1. Superior Corrosion Resistance:

   • Excellent resistance to chloride stress corrosion cracking (SCC) – significantly better than standard 304/316 austenitic grades.

   • Good resistance to pitting and crevice corrosion, especially in acidic chloride environments.

   • Resistant to organic acids, nitric acid, and moderately oxidizing solutions.

2. High Strength:

   • Approximately twice the yield strength of standard austenitic grades (304, 316). Allows for thinner walls and reduced weight while maintaining pressure ratings.

   • High tensile strength.

3. Good Wear and Abrasion Resistance: Enhanced by the ferritic phase microstructure.

4. Favorable Fabricability: Can be welded and formed using standard techniques suitable for duplex stainless steels (requires controlled procedures).

5. Good Toughness: Maintains impact strength down to low temperatures.

Typical Chemical Composition (Weight %):

Mechanical Properties (Typical Annealed Condition):

• Tensile Strength: 620 MPa (min) / ~90 ksi (min)

• Yield Strength (0.2% Offset): 450 MPa (min) / ~65 ksi (min)

• Elongation (% in 50mm): 18% (min)

• Hardness (Brinell): 290 HB (max)

• Impact Toughness (Charpy V): > 100 J @ -20°C / -4°F

Available Forms & Specifications:

• Types: Seamless Pipe & Tube, Welded Pipe & Tube

• Sizes: Wide range available. Common Outer Diameters (OD) from 1/8" (3.17mm) upwards. Wall Thicknesses per schedule (e.g., SCH 5S, 10S, 40S, 80S) or custom.

• Standards: Manufactured to meet or exceed specifications including:

  • ASTM A789 / A790 (Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Tubing/Pipe)

  • ASME SA789 / SA790

  • EN 10216-5

  • Custom specifications available upon request.

• Surface Finish: Annealed & Pickled, Bright Annealed, Polished (various grits). Other finishes available.

Common Applications:

• Chemical and Petrochemical Processing Equipment (heat exchangers, reactors, piping systems)

• Oil & Gas Industry (downhole tubing, flowlines, umbilicals handling corrosive fluids/brines)

• Pulp & Paper Industry (digesters, bleaching equipment)

• Power Generation (FGD systems - Flue Gas Desulfurization)

• Marine & Offshore Applications (seawater handling systems)

• Pollution Control Equipment

• High-Strength Structural Components in corrosive environments.

Temperature Range:

• Recommended Continuous Service: -50°C to +300°C (-58°F to +572°F)

• Short Term Maximum: ~350°C (662°F) - Avoid prolonged exposure above 300°C to prevent embrittlement.

Fabrication Notes:

• Welding: Requires controlled procedures (low heat input, suitable filler metals like 2209 duplex grade) to maintain corrosion resistance and avoid excessive ferrite formation. Post-weld heat treatment may be recommended for critical applications.

• Forming: Good cold workability, but higher strength requires more force than austenitic grades. Avoid excessive cold working without annealing.