Hastelloy C276 Nuts Manufacturer & Exporter in India

Explore Hastelloy C276 Nuts Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.

-200

Min Temp

1100

Max Temp

🌡

1100

Suitable for continuous service up to approximately 1100°C under typical operating conditions.

⚡

800

Typical tensile strength around 800 MPa depending on product form and heat treatment.

🛡

Excellent

Excellent corrosion resistance in a wide range of industrial environments.

⚖

8.9

Typical density is approximately 8.9 g/cm³.

Product Overview

What are Hastelloy C276 Nuts?

Hastelloy C276 nuts are nickel-molybdenum-chromium alloy fasteners manufactured from UNS N10276 bar stock conforming to ASTM B574. The alloy’s exceptional corrosion resistance stems from its high molybdenum content (15-17%) combined with tungsten (3-4.5%), which together suppress pitting, crevice corrosion, and stress corrosion cracking across a broad range of aggressive chemical environments.

With a PREN exceeding 70, Hastelloy C276 nuts outperform every standard stainless steel and most nickel alloys in oxidising and reducing acid service. These nuts are specified under NACE MR0175/ISO 15156 for sour-service flanged connections, chemical reactor closures, and wet scrubber assemblies where fastener integrity is non-negotiable.

Quick Specifications

MaterialHastelloy C276
UNS NumberN10276
DIN Number2.4819
Material StandardASTM B574
Nut Standard (Metric)DIN 934 / DIN 6915 / ISO 4032
Nut Standard (Inch)ASME B18.2.2
Thread FormISO Metric / UNC / UNF
Size RangeM6-M100 / ¼"-4"
Tensile Strength790 MPa (115 ksi) min
Yield Strength355 MPa (52 ksi) min
HardnessMax 35 HRC / 240 HB
? All material certified by NABL-accredited laboratory. PMI available on request.

Complete the Fastener Set

Other Hastelloy C276 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Hastelloy C276 fastener range from certified nickel-molybdenum-chromium superalloy bar stock, including Hastelloy C276 Bolts, Hastelloy C276 Screws, Hastelloy C276 Washers, Hastelloy C276 Studs, and Hastelloy C276 Threaded Rods. All Hastelloy C276 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.

Technical Data

Hastelloy C276 Nuts Dimensions, Sizes & Thread Standards

Hastelloy C276 Nuts are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 934 (hex nuts) / DIN 6915 (heavy hex nuts) / ISO 4032. Custom sizes available. Inch dimensions per ASME B18.2.2. All Hastelloy C276 nuts dimensions are verified against applicable DIN, ISO, and ASME B18 standards

Hex Nut Dimensions - Metric (DIN 934 / ISO 4032)

Size (M)Pitch (mm)A/F (mm)Nut Height (mm)Heavy Hex A/F (mm)Heavy Hex Ht (mm)
M61.0105.0116.0
M81.25136.5157.5
M101.5178.0199.0
M121.751910.02211.0
M162.02413.02714.0
M202.53016.03418.0
M243.03619.04121.0
M303.54624.05026.0
M364.05529.06031.0
M424.56534.07036.0
M485.07538.08241.0
M565.58545.09248.0
M646.09551.010554.0
M726.010558.011561.0
M806.011564.012568.0
M1006.014580.015585.0

Dimensional & Material Standards

StandardCoversThread
DIN 934Hex nuts, standard heightMetric
DIN 6915Heavy hex nuts, high-strengthMetric
ISO 4032Hex nuts, style 1Metric
ISO 4033Hex nuts, style 2 (tall)Metric
ASME B18.2.2Hex & heavy hex nutsUNC/UNF
ASME B16.5Heavy hex nuts for flangesUNC
MSS SP-75Heavy hex nuts, high-pressureUNC
Material StandardRequirement
ASTM B574Bar/rod - UNS N10276
ASTM F467Fastener mechanical properties
NACE MR0175Sour service =35 HRC
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Hastelloy C276 Chemical Composition

Hastelloy C276 Nuts derive their exceptional acid corrosion resistance from a precisely controlled nickel-molybdenum-chromium composition per ASTM. High molybdenum and tungsten content suppresses pitting and reducing-acid attack; ultra-low carbon (0.01% max) eliminates sensitization risk in welded assemblies. Full elemental composition is certified in the EN 10204 MTC supplied with every Hastelloy C276 nuts order from RealBolt.

Chemical Composition per ASTM B574

ElementComposition (%)
Nickel (Ni)Balance (approx. 57% min)
Molybdenum (Mo)15.0-17.0%
Chromium (Cr)14.5-16.5%
Iron (Fe)4.0-7.0%
Tungsten (W)3.0-4.5%
Cobalt (Co)2.5% max
Manganese (Mn)1.0% max
Carbon (C)0.01% max
Silicon (Si)0.08% max
Vanadium (V)0.35% max
? All heats verified by NABL-accredited spectrometry. PMI available on request.

Why Hastelloy C276 Alloy Composition Matters for Nuts

Mo (15–17%) + W (3–4.5%) — Dual Resistance Mechanism
The combined molybdenum and tungsten content gives Hastelloy C276 a PREN exceeding 70, providing outstanding resistance to both pitting and crevice corrosion in chloride-bearing environments. This dual mechanism is particularly critical at nut bearing faces where crevice conditions naturally develop under load.
Ultra-Low Carbon (0.01% max) — Sensitisation Prevention
The extremely low carbon ceiling prevents carbide precipitation at grain boundaries during welding or elevated-temperature service. Hastelloy C276 nuts retain full corrosion resistance in heat-affected zones without requiring post-weld heat treatment, making them ideal for welded flange assemblies.
Broad-Spectrum Acid Resistance
Unlike single-environment alloys, C276 resists both oxidising acids (nitric, chromic) and reducing acids (hydrochloric, sulphuric, phosphoric) simultaneously. This makes it the preferred nut material for multi-service chemical plants where process streams vary in oxidising potential across operating cycles.

Fastener Performance

Hastelloy C276 Nuts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Hastelloy C276 Nuts per ASTM. Hastelloy C276 nuts achieve 800 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Tightening Torque Reference - Hastelloy C276 Nuts

Bolt/Stud SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M12826630
M1619515672
M20390312115
M24680544166
M3013601088264
M3623701896384
M4237803024528
M4856104488694
?? Anti-galling: Use nickel-based anti-seize (Molykote P-37 or Bostik Never-Seez Pure Nickel). Lubricated values assume K=0.15. Never use copper-based anti-seize on nickel alloys - galvanic incompatibility accelerates thread corrosion.

Industry Applications

Hastelloy C276 Nuts Applications — Industries & End Uses

Hastelloy C276 Nuts from RealBolt are specified across chemical processing, pharmaceutical, oil and gas, and FGD where excellent corrosion resistance and 800 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples. Select an industry below to see specific Hastelloy C276 nuts application details and RealBolt stock availability.
Hastelloy C276 heavy hex nuts are the standard specification for flanged closures on hydrochloric acid reactors, sulphuric acid heat exchangers, and wet scrubber column internals. The alloy’s resistance to both oxidising and reducing acids eliminates the need for exotic coatings or frequent fastener replacement in aggressive chemical service.
Heavy hex nuts paired with ASME B16.5 stud bolt sets for wellhead flanges, BOP stack connections, and sour gas pipeline flanges. Fully compliant with NACE MR0175/ISO 15156 hardness requirements. Specified in Shell DEP and ExxonMobil EMSP for H2S-bearing service where stress corrosion cracking of standard alloys is a documented failure mode.
Hastelloy C276 nuts are widely used in FGD absorber tower flange connections, spray header supports, and ductwork flanges where saturated HCl-bearing flue gas at elevated temperatures attacks stainless steel bolting within months. C276 provides multi-year service life in these conditions without pitting or crevice attack.
Nut sets for sterile reactor vessel closures, distillation column flanges, and solvent recovery heat exchangers in pharmaceutical manufacturing. The ultra-low carbon content (0.01% max) ensures no contamination risk from carbide precipitation, and the alloy’s broad chemical resistance accommodates frequent product changeovers involving varied acid and solvent streams.

Hastelloy C276 Nuts Standards & International Certifications

Hastelloy C276 Nuts from RealBolt Engineering Industries are manufactured to internationally recognised fastener dimensional standards covering thread form, tolerances, strength grades, and quality requirements. Every batch ships with EN 10204 MTC 3.1/3.2, PMI (XRF), NACE MR0175/ISO 15156, and NABL-accredited lab reports — available on request for all orders.
Standards
Certifications
ISO 9001:2015NACE MR0175NABL LabPED 2014/68/EUMTC 3.1 / 3.2

Buy Hastelloy C276 Nuts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Hastelloy C276 Nuts — for competitive pricing, EN 10204 MTC 3.1/3.2 documentation, and fast Mumbai dispatch. Standard sizes are ex-stock; custom dimensions accepted with 2–3 week lead time. Request your quote today.

Answers for Buyers

Hastelloy C276 Nuts — Frequently Asked Questions

Browse expert answers to common questions about Hastelloy C276 Nuts from RealBolt — covering acid corrosion resistance, NACE MR0175 compliance, ASTM standards, available sizes, and MTC documentation. Contact our technical team directly for project-specific guidance on Hastelloy C276 nuts selection and pricing.
Hastelloy C276 hex nuts are available to DIN 934 (standard hex), DIN 6915 (heavy hex), ISO 4032 (style 1), ISO 4033 (style 2 tall), and ASME B18.2.2 (inch hex and heavy hex). For ASME B16.5 flange stud bolt sets, heavy hex nuts are supplied per ASME B18.2.2 to match Class 150 through Class 2500 flange requirements. Custom thread forms including BSW, BSF, and BSPP are available with 15 working day lead time.
A standard hex nut (DIN 934 / ISO 4032) has a smaller across-flat dimension and lower height than a heavy hex nut (DIN 6915 / ASME B18.2.2). Heavy hex nuts provide a larger bearing face area, which distributes clamping load more evenly across flange faces – critical in high-pressure piping applications. For ASME B16.5 and ASME B16.47 flange stud bolt sets, heavy hex nuts are always specified. Standard hex nuts are used in structural and general mechanical assemblies where flange load distribution is less critical.
Yes – Hastelloy C276 nuts are fully compliant with NACE MR0175/ISO 15156 for sour service (H2S-bearing) environments when supplied in the annealed condition with hardness not exceeding 35 HRC. Each batch is hardness-tested and documented on the EN 10204 3.1 MTC. For Class 900-2500 sour service flange sets, we supply a full hardness survey report covering every nut in the set as standard practice.
This combination is not recommended for immersed or aggressive chemical service. While there is no significant galvanic incompatibility between C276 and austenitic stainless steel in mild environments, the corrosion resistance mismatch means the stainless stud bolts will corrode preferentially in chloride or acid service, compromising joint integrity. For full corrosion resistance, specify matched C276 stud bolts and nuts from the same heat where possible, or pair with Hastelloy B3 or Inconel 625 studs depending on the specific process environment.

Industrial Cities We Serve:

  • Ahmedabad
  • Aurangabad
  • Bengaluru
  • Chennai
  • Coimbatore
  • Faridabad
  • Gandhidham
  • Greater Noida
  • Gurugram
  • Hazira
  • Hosur
  • Hyderabad
  • Jamnagar
  • Jamshedpur
  • Ludhiana
  • Mumbai
  • Mundra
  • Mysuru
  • Nagpur
  • Nashik
  • Navi Mumbai
  • Noida
  • Pune
  • Rajkot
  • Sanand
  • Surat
  • Thane
  • Tiruppur
  • Vadodara
  • Visakhapatnam

Countries We Export To:

  • US
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  • Mexico
  • Germany
  • UK
  • France
  • Italy
  • Spain
  • Netherlands
  • Belgium
  • Poland
  • Sweden
  • Norway
  • Denmark
  • Turkey
  • UAE
  • Saudi Arabia
  • Qatar
  • Oman
  • Kuwait
  • Bahrain
  • South Africa
  • Egypt
  • Nigeria
  • Australia
  • New Zealand
  • Singapore
  • Malaysia
  • Indonesia
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  • South Korea
  • Japan
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