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Inconel 718 Flanges Supplier in Mumbai – ASTM B564 UNS N07718
Nicorex Alloys is an ISO 9001 / ISO 14001 certified stockist and supplier of Inconel 718 flanges in Mumbai, India. We provide these Alloy 718 flanges in compliance with the ASTM B564 / ASME SB564 standard.
UNS N07718 (Werkstoff 2.4668, Nicrofer 5219 Nb) flanges consist of approximately 50–55% nickel, 17–21% chromium, Nb+Ta 4.75–5.50%, and 2.80–3.30% molybdenum. Inconel 718 flanges deliver 1275 MPa (185 ksi) minimum tensile strength in the age-hardened condition, and retain that strength to 704°C (1300°F). The key is niobium. Nb at 4.75–5.50% forms γ″ (Ni₃Nb) precipitates during ageing, the primary strengthening phase, while Al + Ti form γ′ (Ni₃(Al,Ti)) as a secondary strengthener. Unlike most age-hardenable superalloys, 718’s Nb-based γ″ responds slowly, so the alloy can be welded without spontaneous hardening during cooling.
Inconel 718 flanges are typically supplied in the solution-annealed or precipitation-hardened (aged) condition. Available types include WNRF, BLRF, SORF, SWRF, RTJ, and threaded. Alloy 718 sizes range from NPS 1/2”–24” (ASME B16.5); NPS 26”–60” (ASME B16.47). We provide these flanges in classes 150 through 2500. They are API 6A rated to 20,000 psi, material class, temperature class, PSL level, and heat treatment condition as specified by API 6A, for wellhead service. These Nickel alloy flanges are NACE MR0175 / ISO 15156 compliant in solution-annealed condition. They serve key industries like aerospace, gas turbine, nuclear, oil and gas, and power generation. Each shipment comes with EN 10204/3.1B MTC and PMI.
Inconel 718 Flanges Specifications
Key forged flange specifications for UNS N07718 including standard, types, dimensions, and other details are covered in the table below:
| Specification | ASTM B564 / ASME SB564 |
|---|---|
| Dimensional Standards | ASME B16.5, B16.47, API 6A, EN 1092-1, JIS B2220 |
| Size (ASME B16.5) | NPS 1/2” to NPS 24” |
| Size (ASME B16.47) | NPS 26” to NPS 60” |
| Pressure Classes | 150, 300, 600, 900, 1500, 2500; API 6A: 2000–20,000 psi |
| Face Types | RF, FF, RTJ |
| Flange Types | WNRF, BLRF, SORF, SWRF, RTJ, Threaded |
Chemical Composition of Inconel 718 Flanges
The chemical composition per ASTM B564 for UNS N07718 and its key alloying elements are covered in the table below:
| Element | Ni | Cr | Fe | Nb+Ta | Mo | Ti | Al | C | B | Co | Cu | Mn | Si | P | S |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| wt% | 50.0–55.0 | 17.0–21.0 | Balance | 4.75–5.50 | 2.80–3.30 | 0.65–1.15 | 0.20–0.80 | 0.08 max | 0.006 max | 1.0 max | 0.30 max | 0.35 max | 0.35 max | 0.015 max | 0.015 max |
Nb at 4.75–5.50% forms γ″ (Ni₃Nb) during ageing. This is the primary strengthening phase. Al (0.20–0.80%) and Ti (0.65–1.15%) form γ′ (Ni₃(Al,Ti)) as a secondary strengthener. The γ″ phase responds slowly during cooling, which is why 718 can be welded and cooled without spontaneous hardening, a property that distinguishes it from γ′-dominant superalloys like Waspaloy or René 41.
Mechanical Properties of 718 Inconel Flanges
As per ASTM B564, the mechanical properties of 718 Inconel flanges like tensile and yield strength, elongation, and hardness, in the solution-annealed condition:
| Property | Tensile Strength (min) | Yield 0.2% Offset (min) | Elongation (min) | Hardness (max) |
|---|---|---|---|---|
| Value | 862 MPa (120 ksi) | 414 MPa (60 ksi) | 30% | 363 HBW |
As per ASTM B564, mechanical properties of Alloy 718 flanges in the precipitation-hardened (aged) condition are as follows:
| Property | Tensile Strength (min) | Yield 0.2% Offset (min) | Elongation (min) | Hardness |
|---|---|---|---|---|
| Value (Aged) | 1275 MPa (185 ksi) | 1034 MPa (150 ksi) | 12% | 331–444 HBW (36–44 HRC) |
Inconel 718 Equivalent Grades
The standard equivalent designation of Inconel 718 is UNS N07718, and its Werkstoff Nr. is 2.4668. Some other international designations are listed below:
| UNS | Werkstoff | EN | JIS | AFNOR / GOST |
|---|---|---|---|---|
| N07718 | 2.4668 | NiCr19NbMo | NCF 718 | NC19FeNb / ХН45МВТЮБР |
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Types of Inconel 718 Flanges in Stock
Alloy 718 flanges are forged per ASTM B564 in both solution-annealed and aged conditions. The alloy’s weldability without spontaneous hardening means all types can be field-welded:
Inconel 718 Weld Neck Flange (WNRF)
Inconel 718 Blind Flange (BLRF)
Inconel 718 Socket Weld Flange (SWRF)
Inconel 718 RTJ Flange
Inconel 718 Slip-On Flange (SORF)
Inconel 718 Threaded Flange
Nickel Alloy 718 Lap Joint Flange
Alloy 718 Orifice Flange
Inconel 718 Spectacle Blind Flange
Inconel 718 Reducing Flange
Pressure-Temperature Ratings for Inconel 718 Flanges
Precipitation-hardened 718 flanges hold higher allowable pressures at elevated temperatures than solid-solution alloys (625, C276) in the same pressure class, because the γ″/γ′ precipitates maintain yield strength where solid-solution matrices soften. For API 6A wellhead and Christmas tree assemblies, Alloy 718 is specified for pressure ratings from 2,000 to 20,000 psi at temperatures to 177°C (350°F). Designers must specify whether flanges are solution-annealed or aged, as rated pressures differ between the two conditions.
Industrial Applications of Inconel 718 Flanges
Precipitation-hardened strength to 704°C and excellent weldability drive Alloy 718 flange selection in the 5 key applications:
- Jet engine casing flanges, compressor discharge connections, afterburner ducting joints, and rocket engine turbopump piping.
- Turbine casing flanges, combustor transition connections, and HRSG exhaust joints where creep resistance to 704°C is required.
- HPHT wellhead flanges and Christmas tree connections per API 6A; subsea BOP stack flanges rated to 20,000 psi.
- Reactor pressure vessel internal flanges and steam generator connections per ASME BPVC Section III.
- Compressor discharge flanges, steam turbine casing joints, and supercritical CO₂ cycle piping.
How to Order Inconel 718 Flanges from Nicorex Alloys
Provide the following details to place an order for Inconel 718 flanges:
- Flange Type — WNRF / BLRF / SORF / SWRF / RTJ
- Size — NPS and Schedule (½" to 24"+)
- Pressure Class — 150 / 300 / 600 / 900 / 1500 / 2500
- Face Type — RF / FF / RTJ / T&G
- Material Grade — Inconel 718 / UNS N07718 / W.Nr. 2.4668
- Quantity — Number of pieces or kg
- Standard — ASME B16.5 / B16.47 / ASTM B564
- Additional Requirements — NACE, PMI, solution annealed + aged condition
- Documentation — MTC 3.1/3.2, PMI, Mechanical Properties Report, TPI Certificate
- Delivery — Domestic / International (specify destination)
Custom sizes and API 6A configurations available. Quotation within 24 hours.
Frequently Asked Questions
What is the Price of Inconel 718 Flanges per Kg in India?
Inconel 718 flanges in India generally range between ₹457 and ₹3,000 per kilogram, depending on the condition (annealed vs aged), size, class, and current nickel and niobium rates. Contact Nicorex Alloys for current pricing.
What is the Difference Between Inconel 718 and Inconel 625 Flanges?
718 is precipitation-hardened (1275 MPa tensile aged) for strength to 704°C. 625 is solid-solution strengthened (862 MPa tensile) for broad corrosion resistance to 982°C. Choose 718 for strength; choose 625 for corrosion resistance.
Can Inconel 718 Flanges Be Welded Without Losing Strength?
Yes. 718’s Nb-based γ″ hardening responds slowly, allowing welding without spontaneous hardening during cooling. Post-weld aging restores full precipitation-hardened strength.
What Heat Treatment is Required for Inconel 718 Flanges?
The material should first be solution annealed at 954°C (1750°F) for 1 hour, followed by air cooling. It should then be double aged by heating to 718°C (1325°F) and holding for 8 hours. This is followed by furnace cooling to 621°C (1150°F), holding for a further 8 hours, and finally air cooling.
Are Inconel 718 Flanges Approved for Nuclear Applications?
Yes. Inconel 718 is approved under ASME BPVC Section III for Class 1 nuclear pressure vessel components.
What is the Maximum Service Temperature for Alloy 718 Flanges?
704°C (1300°F) for structural applications requiring full creep resistance. Above this, γ″ precipitates overage and coarsen, causing significant strength loss.
Is Inconel 718 Suitable for Sour Gas (H₂S) Environments?
In solution-annealed condition, Inconel 718 generally meets NACE MR0175 / ISO 15156 requirements. The aged condition has hardness restrictions. Consult ISO 15156-3 Table A.28 for specific environmental limits.