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Inconel 625 Fasteners Supplier in Mumbai, India
Nicorex Alloys is an ISO 9001/ISO 14001-certified supplier, importer and stockist of Inconel 625 fasteners based in Mumbai, India. We supply these fasteners, made according to ASTM F468 for bolts and ASTM F467 for nuts.
Inconel 625 fasteners are nickel-alloy parts built for high temperatures and corrosive conditions. They offer high strength, excellent resistance to pitting and crevice corrosion and very good fatigue performance. The Nb + Mo combination (3.15–4.15% Nb, 8–10% Mo) delivers high as-welded strength through solid-solution hardening, no precipitation heat treatment needed, while 20–23% Cr handles oxidising media. Industries like Subsea Christmas trees, FPSO process flanges and offshore platform piping all demand a single bolt material that resists chloride pitting in warm seawater, survives crevice corrosion under gaskets and matches the weld overlay on CRA-clad equipment. ERNiCrMo-3 (Alloy 625 weld filler) is the universal CRA overlay material, so using 625 bolts on 625-clad flanges eliminates galvanic mismatch.
Also known as UNS N06625 and Werkstoff 2.4856, Inconel 625 fasteners are engineered for demanding high‑corrosion environments. The alloy has a minimum tensile strength of 827 MPa (120 ksi), a minimum yield strength of 414 MPa (60 ksi), and a minimum elongation of 30%, giving it both high strength and good ductility. ASTM F468 requires Alloy 625 to be melted by ESR or VAR processes, which improves cleanliness, toughness, and fatigue life under repeated subsea pressure. These fasteners come in many types, including Alloy 625 hex bolts, stud bolts, socket head cap screws (SHCS), hex nuts, lock nuts, washers, threaded rods, U-bolts and eye bolts. They are typically manufactured in sizes from 1/4” to 1-1/2” as per F468 and M6 to M100 from ASTM B446 bar stock.
Inconel 625 Fastener Specifications
| Standard | ASTM B446 / ASME SB-446 |
|---|---|
| Forms | Bolts, Nuts, Screws, Washers, Studs, Threaded Rods, Hex Bolts, Socket Head Cap Screws, Hex Nuts, Lock Nuts, Stud Bolts |
| Size | M6 – M100 (Metric); 1/4″ – 4″ (Imperial) |
| Length | 3 mm – 200 mm; Custom lengths available |
| Diameter | M6 – M100 (Metric); 1/4″ – 4″ (Imperial) |
| Thread Types | UNC, UNF, Metric Coarse, Metric Fine, BSW, BSF |
| Surface Finishes | Bright Finish, Pickled, Passivated, Hot-Dip Galvanized, Electropolished |
| Available Conditions | Solution Annealed |
Chemical Composition of Inconel 625 Fasteners
| Element | Nickel (Ni) | Chromium (Cr) | Molybdenum (Mo) | Niobium + Tantalum (Nb+Ta) | Iron (Fe) | Cobalt (Co) | Titanium (Ti) | Aluminium (Al) | Carbon (C) |
|---|---|---|---|---|---|---|---|---|---|
| Composition (%) | 58.0 min (Balance) | 20.0–23.0 | 8.0–10.0 | 3.15–4.15 | 5.0 max | 1.0 max | 0.4 max | 0.4 max | 0.10 max |
The 3.15-4.15% niobium stiffens the matrix through solid-solution strengthening and forms NbC carbides that pin grain boundaries. This delivers high as-welded strength without precipitation hardening. The 8-10% Mo gives exceptional pitting and crevice resistance in chloride environments. No post-weld heat treatment is required.
Mechanical Properties of Inconel 625 Fasteners
| Property | Tensile Strength (min) | Yield Strength 0.2% (min) | Elongation (min) |
|---|---|---|---|
| Value | 827 MPa (120 ksi) | 414 MPa (60 ksi) | 30% |
Inconel 625 Fastener Equivalent Grades
| Standard System | UNS | Werkstoff Number | DIN | EN | JIS | GOST | AFNOR |
|---|---|---|---|---|---|---|---|
| Equivalent Grade | N06625 | 2.4856 | NiCr22Mo9Nb | NiCr22Mo9Nb | NCF 625 | ХН75МБТЮ | NC22DNb |
Get Inconel 625 Fasteners at Competitive Prices
Types of Inconel 625 Fasteners Available
Inconel 625 hex bolts
UNS N06625 Heavy hex bolts
Inconel alloy 625 Stud bolts
Alloy 625 Socket head cap screws
Inconel 625 nuts span hex nuts
W.Nr 2.4856 Heavy hex nuts (DIN 934) and lock nuts
UNS N06625 Flat washers & spring washers
Alloy 625 Threaded rods
UNS N06625 U-bolts
Inconel 625 Set screws
Inconel 625 Anchor Bolts
Alloy 625 (fasteners) Eye bolts
Surface Finish and Coating Options
- Plain / self-colour is standard for subsea and marine service (inherent passivation from 23% Cr + 10% Mo)
- Passivated per ASTM A967 (citric acid).
- PTFE coated for anti-galling
- Manganese phosphate for thread lubricity.
- Xylan-coated for subsea bolting assemblies.
- Nickel-based anti-seize recommended.
Industries and Applications for Inconel 625 Fasteners
Inconel 625 fasteners are applicable across various industries for their chloride pitting resistance, ESR/VAR fatigue life and weld filler compatibility drive selection across 5 industries:
- Offshore Oil and Gas / Subsea: Subsea Christmas tree stud bolts, FPSO process equipment flange bolting, platform topsides piping, wellhead connector studs, riser flange bolting. CPT and CCT values exceed super duplex, making 625 the fallback when S32750/S32760 fail pitting qualification in warm seawater service.
- Marine and Desalination: Seawater piping flange bolts, shipboard exhaust system studs, propulsion system hardware, and desalination plant bolting. The 8-10% Mo provides crevice resistance under gaskets and flanges in stagnant seawater conditions.
- Chemical, Petrochemical, and Pollution Control: Chloride process stream equipment, HCl handling, mixed acid reactor bolting and heat exchanger tubesheet studs. FGD scrubber bolting, waste incineration quench system fasteners.
- Aerospace and Nuclear: Exhaust system components, turbine shroud ring bolts, combustion hardware. Reactor core support structures and steam generator bolting.
How to Order Inconel 625 Fasteners from Nicorex Alloys
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Fastener Type - Hex Bolt, Stud Bolt, Socket Head Cap Screw, Nut, Washer, Threaded Rod, Anchor Bolt
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Size - Diameter × Length in mm or inches
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Thread Type - UNC, UNF, BSW, Metric Coarse/Fine
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Material Grade - Inconel 625 / UNS N06625
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Standard - ASTM F468 / ASTM F467 / ASME SA193 B446
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Finish - Bare, Passivated, Pickled
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Condition - Solution Annealed
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Quantity - Number of Pieces or kg
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Additional Requirements - NACE MR0175 compliance, specific heat numbers, subsea / marine service
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Documentation - MTC 3.1 per EN 10204, PMI report, third-party inspection certificate
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Packaging - Standard wooden box / export-grade sea-worthy packing / ISPM 15 compliant
- Delivery Destination - Domestic / International
Frequently Asked Questions
What is the difference between Inconel 625 and 718 for Fasteners?
625 is a corrosion alloy (solid-solution strengthened, 827 MPa tensile and outstanding seawater/chloride resistance). 718 is a strength alloy (precipitation hardened, 1240 MPa tensile). Choose 625 for corrosion-critical subsea/marine bolting. Choose 718 for strength-critical aerospace/wellhead bolting where yield >120 ksi is required.