Duplex 2205 Reducing FlangeASTM A182 · ASME B16.5 · Manufacturer, stockist & exporter, India
UNS S32205 / S31803 · W.Nr 1.4462 · RF
A Duplex 2205 reducing flange is a flange with a smaller bore than its outside dimensions, connecting to a smaller pipe, made from Duplex 2205 to ASTM A182 F51 / F60. A reducing flange changes pipe size at a flanged joint without a separate reducer, saving space and a weld. Use it where the flow disturbance from a sudden change is acceptable.
- ASTM A182
- ASME B16.5
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is a Duplex 2205 Reducing Flange?
- What it is
- A flange with a smaller bore than its outside dimensions, connecting to a smaller pipe
- Material
- ASTM A182 F51 / F60
- Dimensions
- ASME B16.5
- Grade
- Duplex 2205 · UNS S32205
- Best at
- Strength with chloride resistance at a stainless-steel budget
Duplex 2205 Reducing Flange Specification
| Product | Duplex 2205 Reducing Flange |
|---|---|
| Material standard | ASTM A182 F51 / F60 |
| Dimensional standard | ASME B16.5 |
| Sizes | ½" – 24" (ASME B16.5) · 26" – 60" (ASME B16.47) |
| Pressure class | Class 150, 300, 400, 600, 900, 1500, 2500 · PN 6 – PN 100 |
| Facing | RF · FF · RTJ · tongue & groove |
| Bore | To match pipe schedule (state on order) |
| Testing | PMI · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
When to Choose a Reducing Flange
A reducing flange changes pipe size at a flanged joint without a separate reducer, saving space and a weld. Use it where the flow disturbance from a sudden change is acceptable.
- Outside dimensions of the larger size
- Bore / hub for the smaller pipe
- Weld neck, slip-on or threaded styles
More on choosing: Reducing flange guide.
Duplex 2205 Reducing Flange: Why 2205 for reducing flanges
A reducing flange changes pipe size at a flanged joint without a separate reducer, saving space and a weld. Use it where the flow disturbance from a sudden change is acceptable. In Duplex 2205, the choice usually comes down to the medium and temperature — the rows here are the points buyers check for this exact combination.
| Why this grade | Duplex flanges give stainless corrosion resistance with roughly twice the strength of 316L. Duplex 2205 is picked for strength with chloride resistance at a stainless-steel budget. |
|---|---|
| Typical service | Oil & gas — Flowlines, manifolds and topside piping. |
| B16.5 material group | 2.8 |
| Bolting | B7 (coated), B8M or duplex studs, as the project specifies |
| Welding to carbon steel | ER2209 or ER309L(Mo) is used when joining it to carbon steel, under a qualified WPS |
| Matching filler | ER2209 (AWS A5.9) |
| Sour service | Listed in NACE MR0175 / ISO 15156-3 within its limits — state it on the order |
Duplex 2205 Reducing Flange Chemical Composition
| Element | Weight % |
|---|---|
| Chromium | 22.0 – 23.0 |
| Nickel | 4.5 – 6.5 |
| Molybdenum | 3.0 – 3.5 |
| Nitrogen | 0.14 – 0.20 |
| Carbon | 0.030 max |
| Manganese | 2.00 max |
| Silicon | 1.00 max |
| Phosphorus | 0.030 max |
Duplex 2205 Reducing Flange Mechanical Properties
| Solution-annealed plate & sheet | Value |
|---|---|
| Tensile strength | 655 MPa · 95 ksi |
| Yield strength 0.2% | 450 MPa · 65 ksi |
| Elongation | 25% |
| Hardness | 293 HB max |
Full chemistry, properties and equivalents are on the Duplex 2205 grade page.
Other Duplex 2205 flanges
Duplex 2205 Reducing Flanges for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiDuplex 2205 Reducing Flange dimensions — ASME B16.5 Class 150 & 300
Outside diameter, thickness and bolting are set by size and class. Values in mm; thickness excludes the 1.6 mm raised face.
| NPS | Cl 150 OD | Cl 150 thickness | Cl 150 bolt circle | Cl 150 bolts | Cl 300 OD | Cl 300 thickness | Cl 300 bolt circle | Cl 300 bolts |
|---|---|---|---|---|---|---|---|---|
| ½" | 90 | 9.6 | 60.3 | 4 × ½" | 95 | 12.7 | 66.7 | 4 × ½" |
| 1" | 110 | 12.7 | 79.4 | 4 × ½" | 125 | 15.9 | 88.9 | 4 × ⅝" |
| 1½" | 125 | 15.9 | 98.4 | 4 × ½" | 155 | 19.1 | 114.3 | 4 × ¾" |
| 2" | 150 | 17.5 | 120.7 | 4 × ⅝" | 165 | 20.7 | 127.0 | 8 × ⅝" |
| 3" | 190 | 22.3 | 152.4 | 4 × ⅝" | 210 | 27.0 | 168.3 | 8 × ¾" |
| 4" | 230 | 22.3 | 190.5 | 8 × ⅝" | 255 | 30.2 | 200.0 | 8 × ¾" |
| 6" | 280 | 23.9 | 241.3 | 8 × ¾" | 320 | 35.0 | 269.9 | 12 × ¾" |
| 8" | 345 | 27.0 | 298.5 | 8 × ¾" | 380 | 39.7 | 330.2 | 12 × ⅞" |
| 10" | 405 | 28.6 | 362.0 | 12 × ⅞" | 445 | 46.1 | 387.4 | 16 × 1" |
| 12" | 485 | 30.2 | 431.8 | 12 × ⅞" | 520 | 49.3 | 450.8 | 16 × 1⅛" |
Full chart: ASME B16.5 flange dimensions.
Duplex 2205 Reducing Flange — questions buyers ask
Is a reducing flange better than a reducer plus flange?
It saves length and a weld, but a buttweld reducer gives smoother flow. Choose by space and process needs.
What pressure rating does a Duplex 2205 reducing flange have?
It depends on class and temperature. Duplex 2205 forgings are in ASME B16.5 material group 2.8; read your class column in that group's table at the design temperature.
Can Duplex 2205 reducing flanges be welded to carbon steel?
Yes — ER2209 or ER309L(Mo) is used when joining it to carbon steel, under a qualified WPS.
Which standard covers Duplex 2205 reducing flanges?
The material is ASTM A182 F51 / F60; dimensions follow ASME B16.5. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a Duplex 2205 reducing flange?
The alloy price, the size and pressure class, quantity, and the testing and documents required. Send your list and we quote the same working day.
Can you supply Duplex 2205 reducing flanges to NACE MR0175?
Yes. Duplex 2205 is listed in NACE MR0175 / ISO 15156-3 within its limits; state NACE compliance on the order and it is confirmed on the certificate.
What documents do you supply?
EN 10204 3.1 mill certificates as standard, 3.2 with third-party inspection on request, plus dimensional and PMI reports.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026