Hastelloy C22 FlangesASTM B462 UNS N06022 · Manufacturer, stockist & exporter, India
Also sold as Alloy C-22 · UNS N06022 · W.Nr 2.4602 · Nicrofer 5621
Hastelloy C22 flanges are forged to ASTM B462 / B564 and machined to ASME B16.5 (½"–24", Class 150–2500) or ASME B16.47 for larger sizes. It is a nickel–chromium–molybdenum alloy with tungsten, chosen for mixed oxidising and reducing acids, and weld overlays. Kanak Steel & Engineering Co. supplies it with EN 10204 3.1 mill certificates from Mumbai to buyers across India, the Gulf, South-East Asia, South America, Europe, the UK and the USA.
- Stock & mill supply
- EN 10204 3.1 / 3.2
- PMI on every heat
- NACE MR0175 on request
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is Hastelloy C22 Flanges?
Hastelloy C22 flanges is a nickel–chromium–molybdenum alloy with tungsten supplied as flanges to ASTM B462 / B564 (UNS N06022). Buyers specify it for mixed oxidising and reducing acids, and weld overlays. It is also sold as Alloy C-22, UNS N06022, W.Nr 2.4602.
- What it is
- Nickel–chromium–molybdenum alloy with tungsten
- Material
- ASTM B462 / B564
- Dimensions
- ASME B16.5 · B16.47 · EN 1092-1
- Classes
- 150 · 300 · 600 · 900 · 1500 · 2500
- Facing
- RF · FF · RTJ
- Best at
- Mixed oxidising and reducing acids, and weld overlays
Hastelloy C22 Flanges Specification & Sizes
| Material standard | ASTM B462 / B564 |
|---|---|
| Dimensional standards | ASME B16.5 (½"–24") · B16.47 Series A / B (26"–60") · B16.36 orifice · B16.48 line blanks · EN 1092-1 |
| Pressure classes | Class 150, 300, 400, 600, 900, 1500, 2500 · PN 6 – PN 100 |
| Facing | Raised face (RF) · flat face (FF) · ring type joint (RTJ) · tongue & groove |
| Bore | To match the pipe schedule — specify it on the order |
| Types | Weld neck flange · Slip-on flange · Blind flange · Socket weld flange · Threaded flange · Lap joint flange · Long weld neck flange · Orifice flange · Spectacle blind · Reducing flange · Ring type joint flange · Expander flange · Anchor flange · Swivel ring flange |
| Testing | PMI · dimensional · UT of forgings · IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
Standards on this page
Hastelloy C22 Flange Pressure–Temperature Rating
The class is not a pressure: the allowable pressure for C22 flanges comes from the ASME B16.5 table for its material group, and falls as temperature rises (how ratings work). ASTM B462 / B564 is in material group 3.8.
Take the actual pressures from the B16.5 rating table for group 3.8. A class is not a project pressure rating — your piping class sheet and design conditions govern.
Bolting & Gaskets for C22 Flanges
For Hastelloy C22 flanges the usual bolting is B7 (coated), B8M or nickel-alloy studs such as Hastelloy C22 from ASTM B574, as the project specifies — see Hastelloy C22 fasteners. Spiral-wound gaskets for this service usually use a winding in the same or a higher alloy, so the gasket does not corrode first. Facing and gasket options are compared in the flange guide.
Hastelloy C22 Flanges Chemical Composition
| Element | Weight % |
|---|---|
| Nickel | Balance |
| Chromium | 20.0 – 22.5 |
| Molybdenum | 12.5 – 14.5 |
| Iron | 2.0 – 6.0 |
| Tungsten | 2.5 – 3.5 |
| Cobalt | 2.5 max |
| Carbon | 0.015 max |
| Manganese | 0.50 max |
| Vanadium | 0.35 max |
| Silicon | 0.08 max |
Hastelloy C22 Flanges Mechanical Properties
| Solution-annealed plate & sheet | Value |
|---|---|
| Tensile strength | 690 MPa · 100 ksi |
| Yield strength 0.2% | 310 MPa · 45 ksi |
| Elongation | 45% |
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 8.69 g/cm³ |
| Melting range | 1357 – 1399 °C |
| Magnetic | Non-magnetic |
| PREN (approx.) | ≈ 65 |
Hastelloy C22 Equivalent Grades
Values follow ASTM B575 for UNS N06022. Always check against the edition named on your purchase order.
Hastelloy C22 flange dimensions — ASME B16.5 Class 150 & 300
Outside dimensions depend only on size and class, not on the alloy, so C22 flanges bolt to any B16.5 flange of the same 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.
Six-digit Harmonized System heading (nickel alloy, chapter 75). Your country adds its own digits — confirm with your customs broker. All HS codes.
How to Verify Hastelloy C22 Flanges with PMI
Positive material identification with a handheld XRF gun confirms the alloy on the piece itself, in seconds, before it is cut or welded. Hastelloy C22 is most often mixed up with Hastelloy C276 — the table shows which elements tell them apart.
Handheld XRF does not measure carbon or nitrogen; those come from the mill certificate or optical emission (OES) testing. We PMI-test nickel alloys as standard and any grade on request.
| Element | Hastelloy C22 | Hastelloy C276 |
|---|---|---|
| Nickel | Balance | Balance |
| Chromium | 20.0 – 22.5 | 14.5 – 16.5 |
| Molybdenum | 12.5 – 14.5 | 15.0 – 17.0 |
| Tungsten | 2.5 – 3.5 | 3.0 – 4.5 |
| Iron | 2.0 – 6.0 | 4.0 – 7.0 |
| Manganese | 0.50 max | 1.0 max |
Hastelloy C22 Flanges Price — What Decides It
Two quotes for "C22 flanges" can differ by 20% and both be fair. We quote C22 flanges per kg for full sizes and per piece for cut sizes. These six things move the price per kg, so you can compare offers like for like.
Hastelloy C22 flanges by type
Hastelloy C22 Flanges Applications
Hastelloy C22 is specified when the cheaper grade will not survive the service but a higher alloy would be more than the job needs. These are the jobs our buyers use it for.
Hastelloy C22 Flanges vs C276, 625 and 825
| Grade | Flanges standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| Inconel 825 | ASTM B564 | ≈ 31 | Sulphuric and phosphoric acid service, chloride stress-corrosion cracking and sour gas |
| Inconel 625 | ASTM B564 | ≈ 51 | Seawater, high strength and high temperature in one alloy |
| Hastelloy C22 | ASTM B462 / B564 | ≈ 65 | Mixed oxidising and reducing acids, and weld overlays |
| Hastelloy C276 | ASTM B462 / B564 | ≈ 68 | The most aggressive mixed acids, wet chlorine and hypochlorite |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
Hastelloy C22 Corrosion Resistance — Element by Element
Each alloying addition has a job. Knowing which one protects against your medium is the quickest way to judge whether C22 fits.
Higher chromium than C276 gives better resistance to oxidising acids and ferric/cupric chlorides.
Molybdenum keeps strong resistance in reducing acids.
Tungsten improves pitting and crevice resistance.
C22 filler is widely used to weld and overlay other alloys.
How your C22 flanges order runs
- 01Enquiry review — we confirm size, standard edition and documents against your MR or drawing.
- 02Heat selection & PMI — the mill certificate is checked and material is PMI-tested before processing.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked.
- 04Inspection — your third-party inspector witnesses, or we share photos and test reports.
- 05Packing & dispatch — seaworthy packing from Nhava Sheva (JNPT), Mumbai, FOB or CIF, documents sent before the vessel sails.
Standards on this page
Welding & Fabricating Hastelloy C22 Flanges
Hastelloy C22 welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ERNiCrMo-10 (AWS A5.14) |
|---|---|
| Over-alloyed filler | ENiCrMo-10 electrode |
| Preheat | Not required; keep interpass temperature low |
| Cutting | Thermal or abrasive cutting; grind off heat-tinted edges before welding |
Follow your approved WPS; this is general guidance. See also C22 fittings and C22 flanges for the matching pipe-system parts.
How to Order Hastelloy C22 Flanges: RFQ Checklist
Get an accurate quote the first time. Copy this list into your enquiry:
- Flange type and dimensional standard (B16.5 / B16.47 / EN 1092-1)
- Size, pressure class and facing
- Bore / schedule for weld neck and socket weld flanges
- Material standard and grade marking
- Certificate type and extra tests
- Delivery port, Incoterm and required date
Hastelloy C22 flanges for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiHastelloy C22 flanges — questions buyers ask
Is Hastelloy C22 the same as Alloy C-22?
Yes. Alloy C-22, UNS N06022, W.Nr 2.4602 all refer to the same material, and flanges is ordered to ASTM B462 / B564 whichever name is on the enquiry.
Which standard covers Hastelloy C22 flanges?
ASTM B462 / B564 is the material specification for the forging; dimensions follow ASME B16.5 for ½"–24" and ASME B16.47 for 26" and above. European projects use EN 1092-1.
What pressure can a Hastelloy C22 Class 300 flange take?
It depends on temperature. ASTM B462 / B564 is in ASME B16.5 material group 3.8; read the Class 300 column of that group's table at your design temperature.
Which bolts should I use with Hastelloy C22 flanges?
Usually B7 (coated), B8M or nickel-alloy studs such as Hastelloy C22 from ASTM B574, as the project specifies. In corrosive or sour service the bolting material is set by the project specification.
Can a Hastelloy C22 flange be welded to a different pipe material?
Yes — a nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel. Weld neck bores must match the mating pipe schedule.
Can you supply Hastelloy C22 flanges to NACE MR0175?
Yes. Hastelloy C22 is listed in NACE MR0175 / ISO 15156-3 for sour service within that standard's environmental limits. State NACE compliance on the order and it is confirmed on the certificate.
Hastelloy C22 or Inconel 825 — which should I choose?
Hastelloy C22 is chosen for mixed oxidising and reducing acids, and weld overlays. Inconel 825 is the step up when you need more pitting resistance or strength. See the comparison table on this page, or ask us with your process conditions.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026