Higher Proof Strength
2205 has substantially greater minimum 0.2% proof strength than typical annealed 304L or 316L. Apply the full design code before specifying thinner walls.
Global Steel Supply & Processing
ASTM A790/A790M-24 · UNS S32205 / S31803 · SEAMLESS & WELDED
DUPLEX PIPING / INDUSTRIAL PROCUREMENT
Source 2205 duplex stainless pipe by the exact UNS grade, seamless or welded route, NPS, wall schedule, inspection plan and destination.
View technical specifications ↓A clear purchase specification aligns the UNS grade, manufacturing route, wall thickness and quality documents before quotation.
| Ordering parameter | Specify for your project |
|---|---|
| Grade | 2205 duplex stainless steel pipe; UNS S32205 or UNS S31803 specified individually |
| Pipe product standard | ASTM A790/A790M-24 for seamless and straight-seam welded duplex stainless steel pipe |
| Additional process standard | ASTM A928/A928M-14(2025) for applicable electric-fusion-welded pipe using filler metal |
| Dimensions | ASME B36.19-2022; NPS, outside diameter (OD), wall thickness (WT) and Schedule 10S / 40S / 80S |
| Production route | Seamless or automatic straight-seam welded to A790; specify route, heat treatment and inspection |
| Pipe length | Random mill lengths or agreed fixed lengths / cut-to-size |
| Heat-treated condition | Solution-annealed and suitably cooled according to ordered pipe grade and specification |
| Surface / ends | As-finished or pickled, clean / polished when agreed; plain, square or bevelled ends |
| Quality documents | Heat traceability, chemistry / mechanical reports, material test certificate and agreed supplementary tests |
| Commercial inquiry | Specify UNS, standards edition, diameter, wall, process, quantity, destination and delivery terms |
Review the two ASTM A790 UNS chemistries separately. Alloy chemistry supports austenite/ferrite balance and local corrosion resistance.
| Element | UNS S32205 | UNS S31803 |
|---|---|---|
| Chromium (Cr) | 22.00–23.00% | 21.00–23.00% |
| Nickel (Ni) | 4.50–6.50% | 4.50–6.50% |
| Molybdenum (Mo) | 3.00–3.50% | 2.50–3.50% |
| Nitrogen (N) | 0.14–0.20% | 0.08–0.20% |
| Carbon (C) | ≤0.030% | ≤0.030% |
| Manganese (Mn) | ≤2.00% | ≤2.00% |
| Silicon (Si) | ≤1.00% | ≤1.00% |
| Phosphorus (P) | ≤0.030% | ≤0.030% |
| Sulfur (S) | ≤0.020% | ≤0.020% |
| Iron (Fe) | Balance | Balance |
Compare grade-specific tensile properties with the contractual delivery condition and testing requirements.
| Material property | S32205 | S31803 |
|---|---|---|
| Minimum tensile strength Rm | 655 MPa (95 ksi) | 620 MPa (90 ksi) |
| Minimum 0.2% yield strength Rp0.2 | 450 MPa (65 ksi) | 450 MPa (65 ksi) |
| Minimum elongation, 50 mm | 25% | 25% |
| Hardness maximum (ASTM A790 table) | 290 HBW / 30 HRC | 290 HBW / 30 HRC |
| Reference material density | 7.80 g/cm³ for weight estimation | 7.80 g/cm³ for weight estimation |
2205 has substantially greater minimum 0.2% proof strength than typical annealed 304L or 316L. Apply the full design code before specifying thinner walls.
Austenite and ferrite balance comes from chemistry and heat treatment; the as-supplied phase condition may be an inspection requirement.
Request heat-treatment records where required. Improper thermal exposure can impair impact toughness and corrosion performance.
The manufacturing process affects the applicable ASTM standard, weld tests, pipe dimensions and fabrication plans.
Manufactured without a longitudinal production weld seam. Specify ASTM A790 seamless pipe together with solution heat treatment, dimensions, inspection and traceability.
ASTM A790 covers a defined automatic welding route without added filler during welding. For electric-fusion-welded pipe with filler metal, specify the relevant ASTM A928 requirements instead.
Seamless route: identify NPS, wall tolerance and heat treatment.
Welded route: confirm A790 versus A928 and welding inspections.
Identify nominal pipe sizes and wall schedules before comparing cut lengths, masses and delivery quantities.
Typical ASME B36.19 reference dimensions in mm. They are selection references, not an inventory statement; confirm availability and size tolerance by product standard.
| NPS | OD (mm) | SCH 10S WT | SCH 40S WT | SCH 80S WT |
|---|---|---|---|---|
| ½ | 21.3 | 2.11 | 2.77 | 3.73 |
| 1 | 33.4 | 2.77 | 3.38 | 4.55 |
| 2 | 60.3 | 2.77 | 3.91 | 5.54 |
| 3 | 88.9 | 3.05 | 5.49 | 7.62 |
| 4 | 114.3 | 3.05 | 6.02 | 8.56 |
| 6 | 168.3 | 3.40 | 7.11 | 10.97 |
| 8 | 219.1 | 3.76 | 8.18 | 12.70 |
| 10 | 273.1 | 4.19 | 9.27 | 12.70 |
| 12 | 323.9 | 4.57 | 9.53 | 12.70 |
High strength and corrosion performance depend on the supplied structure, not simply the 2205 name.
Duplex 2205 combines ferrite and austenite in a controlled microstructure. Chemistry, solution annealing and cooling practice influence the final balance, weld quality and service behavior.
Confirm grade and condition with material test reports rather than appearance alone.
A practical basis for specifying duplex piping in more aggressive operating environments.
Compared with 304L and 316L, 2205 can offer greater resistance to certain chloride-induced localized corrosion and stress corrosion cracking. Actual performance still depends on temperature, chloride concentration, oxygen, pH, flow, deposits and crevice geometry.
Specify actual solution chemistry, operating temperature and corrosion testing expectations.
Define how your pipe must arrive for fabrication, cleanliness requirements and site installation.
Confirm scale removal, internal cleanliness and surface quality for the ordered pipe production route.
Provide a bevel drawing, welding code and dimensional acceptance requirements for prefabricated piping.
Use appropriate separation, tools and protection to reduce embedded carbon-steel particles and transportation damage.
Specify desired internal or external finish and inspection criteria if polished pipe is required.
Request legible pipe markings or alternative traceability when cut lengths remove original identification.
Match end caps, wrapping and bundles to surface cleanliness and overseas handling.
Typical industrial projects where alloy chemistry, heat treatment, testing and fabrication drive buying decisions.
Duplex piping for selected corrosive process services, subject to chemical compatibility and pressure-code evaluation.
Headers and process lines chosen after assessing chloride, temperature, stagnation and disinfection chemistry.
Selected piping assemblies and process systems requiring welding, testing, material and NACE/ISO confirmation.
Some saline atmospheric and process exposures where engineered corrosion allowance and access are considered.
Equipment lines for process conditions where 2205 is evaluated for mechanical strength and corrosion.
High-strength connections, manifolds and fabricated parts meeting their applicable design standard.
These are possible industry applications, not blanket suitability approvals. Corrosion limits and pressure requirements depend on the individual service.
Calculate nominal mass per meter, per pipe and for a complete order using duplex-specific density.
Choose a nominal size and Schedule 10S / 40S / 80S or enter your own measurements. Uses a 7.80 g/cm³ material density.
Formula: π × (OD − WT) × WT × 0.00780 = kg/m; OD and WT in mm. Density reference: Alleima SAF 2205 pipe technical data.
Specify grade, route and delivery condition in the purchase contract to connect the material to its inspection records.
Duplex piping quality requires grade-specific chemistry, controlled heat treatment and a manufacturing route appropriate for the ordered ASTM pipe standard.
Production and processing capabilities are subject to confirmed mill supply arrangements.
Company-wide supply scale supports broad steel procurement discussions; individual duplex availability, mill origin and certification are confirmed per offer.
Coordinate pipe grade, NPS, schedule, cutting, required reports and export delivery within an itemized quotation.
8 million MT annual steel output and 1 million MT regular inventory are company-wide figures; 2205 pipe availability is confirmed per inquiry.
Request heat numbers, chemistry, mechanical tests, duplex-specific checks and third-party inspection when applicable.
Discuss order quantities, material separation, pipe-bundle dimensions and dispatch documentation for your destination.
Get the right evidence for material identity, mechanical strength, weld quality and the intended corrosion service.
Material certificates and project inspection criteria should be agreed with the purchase order.
Discuss cut lists, weld preparation and cleanliness requirements before your pipes are shipped.
State pipe lengths, cut tolerance, quantities per item and a method of retaining heat traceability.
Send welding groove geometry, end-cleanliness requirements and the relevant spool/isometric drawing.
Specify final surface condition, internal cleanliness and any project-approved passivation practice.
Request size, material grade, heat and line-item markings for easier receiving and fabrication.
Lead times, cutting feasibility, finishing methods and tolerances are confirmed at quotation.
Get grade-by-grade and size-by-size confirmation rather than assuming a broad steel inventory covers each duplex pipe.
| Supply consideration | What to confirm |
|---|---|
| Stock status | Confirm material availability by UNS, route, OD, wall, length and requested certificate; avoid assuming all sizes are stocked |
| Mill source | Identify the actual producer / mill for the quoted heat and delivery lot |
| Procurement quantity | Provide the number of pieces or metric tonnes by size and grade |
| Delivery time | Quote production and shipping schedules after the exact specification is checked |
| Export terms | State destination port / address, INCOTERM and expected receiving schedule |
| Documentation | MTC, packing list, inspection reports and destination-specific documentation by agreement |
Maintain material identification and finish quality from the supplier to your receiving site.
Plan material protection and documentation for long-distance shipments.
Choose a packing method that limits transportation damage and stainless contamination while supporting site sorting and safe handling.
Support material choices with chemistry, minimum strength, corrosion assessment and fabrication requirements.
Typical minimum 0.2% yield strengths in the relevant pipe product standards and annealed conditions. Compare engineering codes, service exposure and fabrication rather than yield alone.
| Pipe grade | Structure | Yield min. | Selection focus |
|---|---|---|---|
| 304 / S30400 | Austenitic | 205 MPa | General Cr-Ni service; evaluate chloride and corrosion risks |
| 304L / S30403 | Low-carbon austenitic | 170 MPa | Welded systems with controlled sensitization risk |
| 316L / S31603 | Mo-bearing austenitic | 170 MPa | Improved resistance over 304L in some chloride environments |
| 2205 / S31803 | Duplex | 450 MPa | Grade-specific chemistry and 620 MPa minimum tensile |
| 2205 / S32205 | Duplex | 450 MPa | Tighter Cr/Mo/N ranges and 655 MPa minimum tensile |
Compare adjacent material families and purchasing options using clearly identified standards and grade numbers.
Related links may point to draft pages until each product is published.
Answers for international buyers covering standards, properties, quality, schedules, corrosion and export procurement.
2205 is a Cr-Ni-Mo-N duplex stainless alloy with both ferritic and austenitic microstructural phases. For pipe, order the specific UNS designation and ASTM A790/A790M edition.
Both are marketed as duplex 2205, but S32205 has higher minimum chromium, molybdenum and nitrogen requirements and a higher ASTM A790 minimum tensile strength. State the exact grade on your purchase order.
ASTM A790/A790M-24 is the currently listed standard for seamless and specified straight-seam welded duplex pipe. Confirm the accepted version in your contract.
A790 includes seamless pipe and a defined automatic straight-seam weld route without filler addition during welding. A928 addresses electric-fusion-welded duplex pipe made with filler metal, with distinct classes and examinations.
Only after project engineering checks corrosion, allowable stress, temperature, joining methods, fittings, pressure-code requirements and service-specific acceptance.
2205 can outperform 316L in some chloride environments, but crevice corrosion and pitting remain possible in warm, stagnant or concentrated seawater. Verify project conditions and corrosion data.
A project must verify NACE MR0175 / ISO 15156 requirements, hardness, material condition and actual H₂S environment. The 2205 name alone is not a sour-service certificate.
ASTM A790/A790M-24 lists 655 MPa minimum tensile, 450 MPa minimum yield and 25% minimum elongation for S32205 in the relevant condition.
Schedules 10S, 40S and 80S are common dimensional designations under ASME B36.19. Confirm the ordered diameter, wall and availability; pressure suitability requires a separate engineering calculation.
Specify heat-traceable chemistry and tensile data, dimensional checks, hydrostatic or nondestructive examination as required, plus any agreed ferrite measurement, ASTM A923 test or third-party hold point.
For OD and wall in millimeters, mass in kg/m = π × (OD − wall) × wall × 0.00780, assuming 7.80 g/cm³ density and nominal dimensions. Exclude packing weight.
Provide UNS S32205 or S31803, ASTM edition, seamless or welded standard, NPS / OD, wall schedule, lengths, quantities, heat treatment, tests, pipe ends, destination and delivery terms.
Send your required grade, dimensions, quantity and destination. Our team will review the inquiry.