Manufacturer of ASTM A790 S31803 Duplex Pipes EN 10204 3.2 Certified UNS S31803
ASTM A790 S31803 Duplex Stainless Steel Pipe | UNS S31803 | High Strength Corrosion Resistant Pipes
Meta Description:
Manufacturer of ASTM A790 S31803/2205 duplex steel pipes. Certified EN 10204 3.1, 100% hydro tested, PREN >38. Ideal for offshore, chemical & oil/gas. Request specs.
Product Overview
Our ASTM A790 seamless duplex pipes (UNS S31803) combine austenitic and ferritic microstructures, delivering 2x the yield strength of 316L stainless steel with exceptional chloride stress corrosion cracking (SCC) resistance. Ideal for high-pressure, corrosive environments.
Key Advantages:
- PREN >38 (Pitting Resistance Equivalent)
- 100% Hydrostatic Testing per ASTM A790
- Low-Temperature Toughness (-50°C / -58°F)
- Certified Traceability: EN 10204 3.1 MTC
Chemical Composition (Wt. %) – Optimized for Corrosion Resistance
Table: Balanced Chemistry of S31803 Duplex Steel Pipe
| Element | Min | Max | Target | Role in Performance |
|---|---|---|---|---|
| Cr | 21.0 | 23.0 | 22.0 | Pitting/Corrosion Resistance |
| Ni | 4.5 | 6.5 | 5.5 | Austenite Stability |
| Mo | 2.5 | 3.5 | 3.0 | Chloride Resistance |
| N | 0.08 | 0.20 | 0.15 | Strength & PRE Boost |
| Mn | - | 2.0 | 1.2 | Deoxidation |
| C | - | 0.030 | 0.02 | Weldability |
| S | - | 0.020 | 0.001 | Machinability |
| P | - | 0.030 | 0.025 | - |
| Fe | Balance |
Equivalent Grades – Global Compliance
Table: Cross-Standard Material Equivalents
| Standard | Grade | Common Name | Similarity |
|---|---|---|---|
| UNS | S31803 | Duplex 2205 | Identical |
| EN | 1.4462 | X2CrNiMoN22-5-3 | Direct Equivalent |
| ASME | SA790 | - | Parent Spec |
| GOST | 03Kh22N6M2 | - | Comparable |
| JIS | SUS 329J3L | - | Near Match |
Mechanical Properties – Engineered for Extreme Service
Table: Room-Temperature Mechanical Properties per ASTM A790
| Property | Requirement | Typical Value | Advantage vs. 316L |
|---|---|---|---|
| Tensile Strength | ≥ 620 MPa | 750-895 MPa | +40% Higher |
| Yield Strength (0.2%) | ≥ 450 MPa | 550-625 MPa | 2x Higher |
| Elongation (%) | ≥ 25% | 28-35% | Superior Ductility |
| Hardness (Rockwell C) | ≤ 32 HRC | 28-32 HRC | Optimal for Sour Service |
| Impact Toughness | ≥ 100 J (-50°C) | ≥140 J | Arctic Readiness |
Dimensional Tolerances – Precision Manufacturing
Table: Permissible Variations per ASTM A790/ASME B36.19
| Parameter | Tolerance (Seamless Pipe) | Critical Application Focus |
|---|---|---|
| OD (Outer Diameter) | ±0.8% or ±0.2mm* | Fitting Compatibility |
| Wall Thickness | +20% / -12.5% | Pressure Integrity |
| Straightness | ≤ 0.2% of length | Offshore Installation |
| Cut Length | +3mm / -0mm | Welding Efficiency |
Application Domains – Where S31803 Duplex Excels
Corrosion-Demanding Environments:
- Offshore Oil & Gas: Seawater injection lines, risers, umbilicals
- Chemical Processing: Acid coolers, chloride-bearing reactors
- Power Generation: FGD (Flue Gas Desulfurization) systems
- Pulp & Paper: Bleach plants, digesters
- Desalination Plants: High-salinity brine heaters
Why Choose YUHONG Duplex S31803 Pipes?
- Full Traceability
- NACE MR0175/ISO 15156 Compliant (Sour Service)
- Global Stock: Sizes 1/2" to 24" (DN15-DN600), SCH 10S to XXS
- Custom Processing: Beveling, polishing, PMI testing
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.