Duplex Stainless Steel 2205 Flanges & Fittings (F51 / F60)
Duplex 2205 has a balanced austenite–ferrite structure that gives roughly twice the yield strength of 316L, with much better resistance to chloride stress corrosion cracking and pitting.
Teshi Group manufactures 2205 flanges to ASTM A182 F51 and F60 and fittings to ASTM A815, heat treated and tested for ferrite content and detrimental phases before dispatch.
Duplex 2205 — grades, chemistry and properties
Grades and ASTM / ASME specifications
| Grade | Forged flanges & fittings | Butt weld fittings | Plate | Pipe |
|---|---|---|---|---|
| 2205 (S31803)UNS S31803 · W.Nr. 1.4462 | ASTM A182 F51 | ASTM A815 WPS31803 | ASTM A240 | ASTM A790 |
| 2205 (S32205)UNS S32205 · W.Nr. 1.4462 | ASTM A182 F60 | ASTM A815 WPS32205 | ASTM A240 | ASTM A790 |
Chemical composition (weight %, maximum unless a range is given)
| Grade | C | Mn | Si | Cr | Ni | Mo | N |
|---|---|---|---|---|---|---|---|
| 2205 (S31803) | 0.030 | 2.00 | 1.00 | 21.0–23.0 | 4.5–6.5 | 2.5–3.5 | 0.08–0.20 |
| 2205 (S32205) | 0.030 | 2.00 | 1.00 | 22.0–23.0 | 4.5–6.5 | 3.0–3.5 | 0.14–0.20 |
Mechanical properties (minimum, room temperature)
| Grade | Tensile strength | Yield strength (0.2 %) | Elongation | Note |
|---|---|---|---|---|
| 2205 (S31803) | 620 MPa (90 ksi) | 450 MPa (65 ksi) | 25 % | PREN ≈ 33 |
| 2205 (S32205) | 655 MPa (95 ksi) | 450 MPa (65 ksi) | 25 % | PREN ≈ 35 |
Values are minimums and limits from the governing ASTM / ASME specifications, summarised for convenience. The current edition of the specification takes precedence; confirm requirements against your project specification.
Where it is used
- Brackish and produced-water lines
- Chemical process piping and vessels
- Oil and gas gathering and flow lines
- Pulp and paper digesters
- Hydrometallurgical leach circuits
Testing & certification
- Solution annealed and water quenched
- Ferrite content check, typically 35–65 %
- ASTM A923 tests for detrimental intermetallic phases when specified
- Impact testing and PMI as specified
Duplex 2205 products we manufacture
All products
01OEM manufacturerWeld Neck Flanges
ASME B16.5 · ASME B16.47
02OEM manufacturerBlind Flanges
ASME B16.5 · ASME B16.47
03OEM manufacturerSlip-On Flanges
ASME B16.5 · EN 1092-1 Type 12
04OEM manufacturerButt Weld Elbows
ASME B16.9 · ASME B16.25
05OEM manufacturerButt Weld Tees
ASME B16.9 · ASME B16.25
06OEM manufacturerWeldolets & Sockolets
MSS SP-97 · ASME B16.11
Industries and projects
Oil & Gas
Where Duplex 2205 is specified
ViewIndustryChemical & Petrochemical
Where Duplex 2205 is specified
ViewIndustryMining & Smelters
Where Duplex 2205 is specified
ViewProjectsMega-projects & EPC supply
Project BOQs, shutdowns and annual rate contracts
ViewGrade data sheets
Other materials
Duplex 2205 by product
FAQ
Duplex 2205: common questions
What is the difference between F51 and F60?
Both are duplex 2205. F51 is UNS S31803 (Cr 21–23 %, Mo 2.5–3.5 %); F60 is UNS S32205 with tighter, higher limits (Cr 22–23 %, Mo 3.0–3.5 %, N 0.14–0.20 %). Most 2205 today is dual-certified to both.
How strong is duplex 2205 compared with 316L?
Minimum yield strength is 450 MPa for duplex 2205 against 170 MPa for 316L forgings, which allows thinner, lighter components for the same pressure.
Which standard covers duplex butt weld fittings?
ASTM A815 covers wrought ferritic, ferritic/austenitic and martensitic stainless fittings, including WPS31803 and WPS32205, with dimensions to ASME B16.9.
Do you test duplex flanges for intermetallic phases?
Yes. When the order specifies it, duplex flanges and fittings are tested to ASTM A923 and checked for ferrite content, and the results are reported on the EN 10204 3.1 certificate.
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