Materials · Duplex
Duplex S31803 fasteners
HAGUE FASTENERS makes duplex S31803 fasteners to order: stud bolts, bolts, nuts and machined parts in 22% chromium duplex stainless steel, UNS S31803 and S32205, made to your drawing in our Willenhall facility.
F51
Also UNS S32205, 1.4462 and SAF 2205
450 MPa
Minimum yield strength
PREn 33 to 34
Typical pitting resistance equivalent
1 to 500
Prototypes to batches of several hundred
About the alloy
Strength and chloride resistance in one steel
HAGUE FASTENERS makes Duplex S31803 fasteners in the UK for oil and gas, chemical, pulp and paper and seawater service. S31803, often dual certified as S32205 and known as F51 or 1.4462, has a mixed austenitic and ferritic structure that gives it outstanding resistance to chloride pitting, crevice corrosion and stress corrosion cracking.
It also has roughly twice the yield strength of 316 stainless steel. For harsher duty, step up to super duplex S32750 or S32760.
At a glance
- 22% chromium duplex stainless steel
- Resists chloride pitting and stress corrosion cracking
- Listed in NACE MR-01-75 for oil and gas service
- NORSOK MDS D41 to D45, D47 and D48
Composition
Duplex S31803 chemical composition
Percentage by weight. Other: PREn 33 to 34 typical.
| Element | Min % | Max % |
|---|---|---|
| Nickel (Ni) | 4.50 | 6.5 |
| Molybdenum (Mo) | 3.00 | 3.50 |
| Silicon (Si) | – | 1.00 |
| Chromium (Cr) | 22.00 | 23.00 |
| Carbon (C) | – | 0.03 |
| Manganese (Mn) | – | 2.00 |
| Nitrogen (N) | 0.08 | 0.20 |
| Sulphur (S) | – | 0.02 |
| Phosphorus (P) | – | 0.03 |
| Iron (Fe) | Bal | – |
Properties
Mechanical properties
Minimum strength and maximum hardness values.
| Property | Value |
|---|---|
| Tensile strength | 620 MPa min. |
| Yield strength (0.2% offset) | 450 MPa min. |
| Elongation in 2 in (50 mm) or 4D | 25% |
| Hardness | 270 HB max |
This data is for general information only and may change without notice. HAGUE FASTENERS LIMITED believes it to be accurate but gives no warranty as to its accuracy or completeness and accepts no liability for its use. Actual properties may vary, and nothing here guarantees suitability for a particular use.
Equivalents and applications
Duplex S31803 equivalents and typical uses
Alternative designations
UNS S31803, UNS S32205, Werkstoff 1.4462, EN 1.4462. ASTM A240, A276, A479, A789, A790, A182 (Grade F51), A923. ASME SA-240, SA-479, SA-789, SA-790, SA-182 (Grade 51), ASME P-group 10H. X2CrNiMoN22.5.3, Z2CND22.05Az, F51 (329LN) / F60, SAF 2205 SANMAC, URANUS 45N, FALC223, SS2377, 318S13, 332C15, 1.4470, Ralloy 2377. NORSOK MDS D41 to D45, D47 and D48. Listed in NACE MR-01-75 for oil and gas service.
Typical applications
- Pulp mill bleach plants
- Seawater heat exchangers
- Chemical process equipment
- Oil and gas process and pipework bolting
What we make
Fasteners we make in Duplex S31803
Certification and testing
Certified, traceable and tested
Bar comes from approved UK, EU or US mills, with heat numbers carried through to release. Testing is by independent UKAS-accredited laboratories, with EN 10204 3.1 or 3.2 certificates as required. See quality and testing.
- Mill certificates and heat traceability
- PMI and chemical analysis
- Solution annealing by approved partners, with furnace charts
- Laser-marked heat codes or part numbers
Questions
Frequently asked questions
What is the equivalent of duplex S31803?
Duplex S31803 is equivalent to F51, EN 1.4462 and SAF 2205, and is commonly dual certified as UNS S32205.
Is duplex stainless steel magnetic?
Yes. Duplex stainless steels such as S31803 contain ferrite and are magnetic, unlike fully austenitic grades such as 316.
Can you make Duplex S31803 fasteners to ASTM A182 F51?
Yes. We make studs, bolts and nuts from bar to ASTM A182 F51, A276 or A479, or to the NORSOK data sheet you specify.
When should I choose super duplex instead of S31803?
Choose super duplex when the duty is harsher, for example warm seawater or higher chloride levels, where its higher pitting resistance is needed.
Duplex S31803 enquiry?
Send us your drawing or specification
Tell us the sizes, quantity and documentation you need, and we will reply quickly.