Incoloy 800 / 800H / 800HT Orifice FlangeASTM B564 · ASME B16.36 · Manufacturer, stockist & exporter, India
Alloy 800 · UNS N08800 / N08810 / N08811 · ORF
An Incoloy 800 / 800H / 800HT orifice flange is a pair of weld neck or slip-on flanges with pressure taps that hold an orifice plate, made from Incoloy 800 / 800H / 800HT to ASTM B564. Orifice flanges are used for flow measurement. Each flange has two ½" NPT pressure-tap holes, and jack screws help separate the pair to change the plate.
- ASTM B564
- ASME B16.36
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an Incoloy 800 / 800H / 800HT Orifice Flange?
- What it is
- A pair of weld neck or slip-on flanges with pressure taps that hold an orifice plate
- Material
- ASTM B564
- Dimensions
- ASME B16.36
- Grade
- Incoloy 800 / 800H / 800HT · UNS N08800
- Best at
- Furnaces, petrochemical heaters and high-temperature piping
Incoloy 800 / 800H / 800HT Orifice Flange Specification
| Product | Incoloy 800 / 800H / 800HT Orifice Flange |
|---|---|
| Material standard | ASTM B564 |
| Dimensional standard | ASME B16.36 |
| Sizes | 1" – 24" (ASME B16.36) |
| Pressure class | Class 300 – 2500 |
| 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 an Orifice Flange
Orifice flanges are used for flow measurement. Each flange has two ½" NPT pressure-tap holes, and jack screws help separate the pair to change the plate.
- Class 300 minimum per ASME B16.36
- Supplied in pairs with jack screws
- Pressure taps: ½" NPT, two per flange
More on choosing: Orifice flange guide.
Incoloy 800 / 800H / 800HT Orifice Flange: Why 800 for orifice flanges
Orifice flanges are used for flow measurement. Each flange has two ½" NPT pressure-tap holes, and jack screws help separate the pair to change the plate. In Incoloy 800 / 800H / 800HT, 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 | Nickel-alloy flanges are used where acids, chlorides or heat defeat stainless. Incoloy 800 / 800H / 800HT is picked for furnaces, petrochemical heaters and high-temperature piping. |
|---|---|
| Typical service | Petrochemical — Steam-methane reformer and ethylene furnace piping. |
| Bolting | B7 (coated), B8M or nickel-alloy studs such as Incoloy 800 / 800H / 800HT from ASTM B408, as the project specifies |
| Welding to carbon steel | A nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel |
| Matching filler | ERNiCr-3 (AWS A5.14) |
Incoloy 800 / 800H / 800HT Orifice Flange Chemical Composition
| Element | Weight % |
|---|---|
| Nickel | 30.0 – 35.0 |
| Chromium | 19.0 – 23.0 |
| Iron | 39.5 min |
| Carbon | 0.10 max (800) · 0.05 – 0.10 (800H) |
| Aluminium | 0.15 – 0.60 |
| Titanium | 0.15 – 0.60 |
| Copper | 0.75 max |
| Manganese | 1.5 max |
Incoloy 800 / 800H / 800HT Orifice Flange Mechanical Properties
| Annealed plate | Value |
|---|---|
| Tensile strength | 520 MPa · 75 ksi (800) · 450 MPa · 65 ksi (800H) |
| Yield strength 0.2% | 205 MPa · 30 ksi (800) · 170 MPa · 25 ksi (800H) |
| Elongation | 30% |
Full chemistry, properties and equivalents are on the Incoloy 800 / 800H / 800HT grade page.
Other Incoloy 800 / 800H / 800HT flanges
Incoloy 800 / 800H / 800HT Orifice Flanges for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiIncoloy 800 / 800H / 800HT Orifice Flange — questions buyers ask
Why is the minimum class 300 for orifice flanges?
ASME B16.36 starts at Class 300 so the flange is thick enough to drill the pressure taps radially.
Can Incoloy 800 / 800H / 800HT orifice flanges be welded to carbon steel?
Yes — a nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel.
Which standard covers Incoloy 800 / 800H / 800HT orifice flanges?
The material is ASTM B564; dimensions follow ASME B16.36. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a Incoloy 800 / 800H / 800HT orifice 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.
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