Super Duplex 2507 (F53) & UNS S32760 (F55) Flanges & Fittings
Super duplex stainless steels raise chromium, molybdenum and nitrogen to give a pitting resistance equivalent number (PREN) of 40 or more, for seawater, high-chloride brines and sour service where duplex 2205 is not enough.
Teshi Group manufactures super duplex flanges to ASTM A182 F53 and F55 and fittings to ASTM A815, with heat treatment, ferrite and ASTM A923 testing, and PMI on every piece.
Super Duplex — grades, chemistry and properties
Grades and ASTM / ASME specifications
| Grade | Forged flanges & fittings | Butt weld fittings | Plate | Pipe |
|---|---|---|---|---|
| 2507 (S32750)UNS S32750 · W.Nr. 1.4410 | ASTM A182 F53 | ASTM A815 WPS32750 | ASTM A240 | ASTM A790 |
| S32760 (Zeron® 100 type)UNS S32760 · W.Nr. 1.4501 | ASTM A182 F55 | ASTM A815 WPS32760 | ASTM A240 | ASTM A790 |
Chemical composition (weight %, maximum unless a range is given)
| Grade | C | Mn | Si | Cr | Ni | Mo | Cu | N | W |
|---|---|---|---|---|---|---|---|---|---|
| 2507 (S32750) | 0.030 | 1.20 | 0.80 | 24.0–26.0 | 6.0–8.0 | 3.0–5.0 | 0.50 | 0.24–0.32 | — |
| S32760 (Zeron® 100 type) | 0.030 | 1.00 | 1.00 | 24.0–26.0 | 6.0–8.0 | 3.0–4.0 | 0.50–1.00 | 0.20–0.30 | 0.50–1.00 |
Mechanical properties (minimum, room temperature)
| Grade | Tensile strength | Yield strength (0.2 %) | Elongation | Note |
|---|---|---|---|---|
| 2507 (S32750) | 800 MPa (116 ksi) | 550 MPa (80 ksi) | 15 % | PREN ≥ 41 |
| S32760 (Zeron® 100 type) | 750 MPa (109 ksi) | 550 MPa (80 ksi) | 25 % | PREN ≥ 40 |
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
- Seawater reverse-osmosis desalination
- Offshore firewater and seawater injection
- Sour service to NACE MR0175 / ISO 15156 when specified
- High-chloride hydrometallurgical leaching
- Subsea manifolds and process piping
Testing & certification
- Solution annealed and water quenched
- ASTM A923 Methods A/B/C when specified
- Ferrite content 40–60 % by ASTM E562 point count
- ASTM G48 ferric chloride pitting test when specified
- Hardness checks for NACE MR0175 / ISO 15156 sour service when specified
- PMI on every piece
Super Duplex 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 Super Duplex is specified
ViewIndustryWater Treatment & Desalination
Where Super Duplex is specified
ViewIndustryMining & Smelters
Where Super Duplex is specified
ViewProjectsMega-projects & EPC supply
Project BOQs, shutdowns and annual rate contracts
ViewOther materials
Super Duplex by product
FAQ
Super Duplex: common questions
What is the PREN of super duplex 2507?
PREN = Cr + 3.3 Mo + 16 N. For UNS S32750 (ASTM A182 F53) it is typically 41–43, and super duplex is generally defined as PREN of at least 40.
Is UNS S32760 the same as Zeron 100?
Zeron® 100 is a registered trade name for an alloy within UNS S32760 (ASTM A182 F55). S32760 adds 0.5–1.0 % tungsten and copper to 2507-type chemistry. Teshi Group supplies S32760 to the ASTM specification.
Can super duplex flanges be supplied for sour service?
Yes. When NACE MR0175 / ISO 15156 is specified, hardness and heat treatment are controlled and reported to meet its limits for duplex stainless steels.
Which test confirms there are no intermetallic phases?
ASTM A923 Method A (etch screening), Method B (Charpy impact) and Method C (ferric chloride corrosion) detect sigma and other detrimental phases in duplex and super duplex steels.
Super duplex stainless steel grade data sheets
Super duplex stainless steel overview →Chemical composition, mechanical properties and PDF data sheet for each grade.
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