Uses & Specifications
of Inconel Fasteners
Mumbai · India
What Makes Uses & Specifications of Inconel Fasteners
Inconel’s nickel-chromium base gives it a combination that few other alloy families offer at once: mechanical strength that holds up well beyond the temperature where stainless steel has already softened, resistance to oxidation and carburization in atmospheres that would scale ordinary steel, and corrosion resistance across a genuinely wide range of process chemistries. That combination is precisely why it shows up in industries as different as aerospace, oil and gas, and power generation — each is really asking the same underlying question in a different form: can this fastener hold its clamping force and resist attack under conditions that would defeat cheaper alternatives?
Uses and specifications are two sides of the same decision. Knowing that a fastener is going into a gas turbine hot section tells you almost immediately that you’re likely looking at Inconel 718 for its age-hardened strength, or X-750 if stress relaxation resistance matters more. Knowing it’s going into sour gas wellhead flanges points toward Inconel 625 for its corrosion resistance. The specification follows from the application — which is why this page walks through uses first, then the exact details buyers need to provide to get a correct quote.
Akbar Fasteners Pvt. Ltd. exports to over 50 countries, and our Inconel range across all four core grades is manufactured with the same ISO 9001:2015 quality system and full mill test documentation as our Incoloy, Monel, and Hastelloy range.
From Application to Accurate Quote
Application-First Grade Selection
We start from the temperature, load, and environment you describe and recommend the grade that actually fits, not the one that’s simplest to quote.
Full Four-Grade Coverage
Inconel 625, 718, 600, and X-750 manufactured under one quality system, so mixed-grade orders ship together.
Specification Checklist Support
We help first-time Inconel buyers fill in the specification gaps their drawing doesn’t cover, before quoting rather than after.
Full Mill Test Traceability
Every batch traceable by heat number with mechanical property verification confirming true grade compliance.
Uses of Inconel Fasteners By Industry
Aerospace & Gas Turbines
Inconel 718 is the workhorse structural fastening grade in jet engine hot sections and airframe assemblies, chosen for its precipitation-hardened strength retention at elevated temperature. X-750 covers spring and clamp-load applications needing stress-relaxation resistance.
Oil & Gas Sour Service
Inconel 625 fastens wellhead, subsea, and flowline flanges exposed to H2S, CO2, and chlorides — environments where standard duplex or stainless would eventually fail.
Power Generation & Boilers
High-temperature boiler tube supports, header fastening, and turbine casing bolting rely on 718 or 625 depending on whether structural strength or corrosion resistance dominates.
Chemical & Petrochemical Processing
Reactor vessels and piping handling aggressive acids or elevated-temperature process streams commonly specify Inconel 625 fastening for its broad corrosion resistance.
Heat Treatment & Furnace Equipment
Inconel 600’s oxidation and carburization resistance makes it the default for furnace fixtures, muffles, and fastening exposed to sustained extreme heat.
Nuclear & Marine Applications
High-integrity fastening in nuclear plant components and marine seawater-adjacent hot equipment, where both strength and corrosion resistance are non-negotiable.
Specification Checklist for Ordering
Provide these details and we can confirm grade, size, and lead time in one round.
Grade (625 / 718 / 600 / X-750)
If unsure, describe temperature and corrosion exposure and we’ll recommend the grade.
Fastener Type & Size
Bolt, nut, stud bolt, or washer, with diameter, length, and thread type (UNC/UNF/Metric).
Applicable Standard
ASTM A193/A320 for stud bolts, ASTM A276 for bar stock, or an equivalent standard your project references.
Service Temperature Range
Minimum and maximum expected service temperature — this alone often narrows the grade choice significantly.
Corrosive Environment Details
Sour gas, chlorides, specific acids, or general atmospheric — this determines whether 625 or another grade is needed.
Testing & Documentation Needs
Standard MTC, NABL-accredited testing, or additional certification your end client requires.
Surface Finish
As-machined, passivated, or coated, depending on the application and any client specification.
Quantity & Delivery Terms
Order quantity and preferred Incoterm (FOB, CFR, CIF) so we can quote landed cost accurately.
Drawing or Reference Sample
A drawing, sketch, or reference sample if the fastener is non-standard, to avoid dimensional ambiguity.
Grade-to-Use Quick Reference
A condensed version of the grade selection logic covered above — useful as a quick reference once you already know roughly which industry and condition you’re specifying for.
| Primary Use Case | Recommended Grade | Key Property Driving Choice | Typical Standard |
|---|---|---|---|
| Sour Gas / Marine Corrosion | Inconel 625 | Chloride & H2S corrosion resistance | ASTM A193 / A276 |
| Structural High-Temp Strength | Inconel 718 | Precipitation-hardened strength retention | ASTM A637 / AMS 5662 |
| Furnace / Extreme Oxidation | Inconel 600 | Oxidation & carburization resistance | ASTM A276 / B166 |
| Springs / Preload Retention | Inconel X-750 | Stress-relaxation resistance at heat | ASTM A637 / AMS 5667 |
Inconel Fastener Technical Specifications
Typical Alloying Elements by Grade
- Inconel 625 Ni-Cr, +9% Mo, +3.6% Nb
- Inconel 718 Ni-Cr-Fe, +5.5% Nb, +3% Mo
- Inconel 600 ~72% Ni, ~15% Cr, ~8% Fe
- Inconel X-750 +0.7% Al, +2.5% Ti, +1% Nb
- Exact composition Grade-specific — see MTC
Property Ranges (grade dependent)
- Tensile Strength 550–1375 MPa
- Yield Strength 240–1170 MPa
- Elongation 20–50%
- Age-Hardenable Grades 718, X-750
- Testing MTC / NABL on request
Available Dimensions
- Metric Diameter M6 – M64
- Imperial Diameter 1/4″ – 4″
- Stud Length Custom to drawing
- Thread Type UNC / UNF / Metric
- Finish As-machined / Passivated
Standard Export Documentation
Prepared as standard practice for every Inconel fastener shipment.
Mill Test Certificate (MTC)
Heat number, chemical composition, and mechanical property verification for every lot.
Certificate of Conformance
Confirms the shipment matches the purchase order specification and grade in full.
Certificate of Origin (COO)
Confirms India as country of manufacture for destination customs purposes.
Commercial Invoice & Packing List
Itemized value, Incoterm, and detailed carton/weight breakdown for customs clearance.
NABL Accredited Test Reports
Independent mechanical and chemical testing available on request for critical applications.
Bill of Lading
Ocean or air freight shipping document confirming carrier, mode, and consignee details.
Internationally Recognised Standards Coverage
Related Fastener Grades & Materials
Different Types of Inconel Fasteners
A detailed grade-by-grade comparison for choosing between the four Inconel grades.
View Inconel Grades →Hastelloy B-3 Stud Bolts
Our established nickel-molybdenum alloy fastening line for severe reducing acid service.
View Hastelloy B-3 →Different Types of Monel Fasteners
Nickel-copper grades built for seawater and hydrofluoric acid service instead of high heat.
View Monel Grades →Fastener Applications By Industry
A broader guide to matching fastener material grades to the right industry and environment.
View Applications Guide →Tell Us Your Use Case,
We’ll Confirm the Specification
Describe the industry, temperature, and environment — and we’ll confirm the right Inconel grade and full specification for your order. Akbar Fasteners Pvt. Ltd. responds within 24 hours.
Sales: +91 724 0000 733 · Support: +91 800 9315 333 · sales@akbarfasteners.in