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Incoloy 800HT Nuts Manufacturer & Exporter in India

Explore Incoloy 800HT Nuts Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.
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-196

Min Temp

870

Max Temp

🌡

870

Suitable for continuous service up to approximately 870°C under typical operating conditions.

⚡

620

Typical tensile strength around 620 MPa depending on product form and heat treatment.

🛡

Very Good

Very Good corrosion resistance in a wide range of industrial environments.

⚖

8

Typical density is approximately 8.0 g/cm³.

Product Overview

What are Incoloy 800HT Nuts?

Incoloy 800HT nuts are high-temperature, corrosion-resistant fasteners manufactured from nickel-iron-chromium alloy UNS N08811, conforming to ASTM B408 and ASTM B564. The alloy’s enhanced carbon (0.06-0.10%) and aluminum/titanium content provide superior creep and rupture strength compared to standard Incoloy 800, making these nuts ideal for bolted joints exposed to prolonged service above 600°C.

Incoloy 800HT nuts are specified for critical applications in heat exchangers, reformer outlet manifolds, and petrochemical furnace hardware, where resistance to oxidation, carburization, and chloride stress corrosion cracking is essential. All nuts are supplied with full traceability and EN 10204 3.1 certification.

Quick Specifications

MaterialIncoloy 800HT
UNS NumberN08811
DIN Number1.4959 / 1.4876
Material StandardASTM B408 / ASTM B564
Nut Standard (Metric)DIN 934 / ISO 4032
Nut Standard (Inch)ASME B18.2.2
Thread FormISO Metric / UNC / UNF
Diameter RangeM6-M64 / ¼"-2½"
Tensile Strength600 MPa (87 ksi) min
Yield Strength275 MPa (40 ksi) min
HardnessMax 95 HRB / 200 HB
? All material certified by NABL-accredited laboratory. PMI and hardness survey available on request.

Complete the Fastener Set

Other Incoloy 800HT Fastener Products Available from RealBolt

RealBolt also manufactures the complete Incoloy 800HT fastener range from certified iron-nickel-chromium alloy bar stock, including Incoloy 800HT Bolts, Incoloy 800HT Screws, Incoloy 800HT Washers, Incoloy 800HT Studs, and Incoloy 800HT Threaded Rods. All Incoloy 800HT fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
Incoloy 800HT Bolts
Incoloy 800HT Screws
Incoloy 800HT Washers
Incoloy 800HT Studs
Incoloy 800HT Threaded Rods

Technical Data

Incoloy 800HT Nuts Dimensions, Sizes & Thread Standards

Incoloy 800HT Nuts are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 934 (hex nut) / ISO 4032. Custom thread pitches and heavy hex patterns available. Inch dimensions per ASME B18.2.2. All Incoloy 800HT nuts dimensions are verified against applicable DIN, ISO, and ASME B18 standards before

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

Size (M)Pitch (mm)A/F (mm)Height (mm)
M61.0105.0
M81.25136.5
M101.5178.0
M121.751910.0
M162.02413.0
M202.53016.0
M243.03619.0
M303.54624.0
M364.05529.0
M424.56534.0
M485.07538.0
M565.58545.0
M646.09551.0

Dimensional & Material Standards

StandardCoversThread
DIN 934Hex nutsMetric
ISO 4032Hex nutsMetric
ASME B18.2.2Hex & heavy hex nutsUNC/UNF
DIN 439Thin hex nutsMetric
ISO 4035Thin hex nutsMetric
Material StandardRequirement
ASTM B408Bar/rod - UNS N08811
ASTM B564Forged nuts
ASTM F468Mechanical properties
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Incoloy 800HT Chemical Composition

Incoloy 800HT Nuts are produced from an iron-nickel-chromium alloy with controlled nickel (30–46%), chromium (19–23%), and molybdenum content per ASTM. Nickel and chromium together resist high-temperature oxidation to 1093°C in 800H grades, while molybdenum and copper additions in Incoloy 825 provide sulfuric and phosphoric acid resistance.

Chemical Composition per ASTM B408 / B564

ElementComposition (%)
Nickel (Ni)30.0-35.0
Chromium (Cr)19.0-23.0
Iron (Fe)39.5 min
Carbon (C)0.06-0.10
Aluminum (Al)0.25-0.60
Titanium (Ti)0.25-0.60
Manganese (Mn)1.5 max
Silicon (Si)1.0 max
Sulfur (S)0.015 max
Copper (Cu)0.75 max
? All heats verified by NABL-accredited spectrometry. PMI available on request.

Why Incoloy 800HT Alloy Composition Matters for Nuts

High Nickel & Chromium — Oxidation Resistance
The high nickel and chromium content ensures Incoloy 800HT nuts resist scaling and oxidation at temperatures up to 1100°C, making them ideal for furnace and heat exchanger assemblies.
Al + Ti (0.25–0.60%) — Creep Strength
Aluminum and titanium additions promote gamma prime formation, significantly improving creep and rupture strength for bolted joints under sustained high temperatures.
Controlled Carbon — Stress Rupture Life
The specified carbon range (0.06–0.10%) in 800HT prevents grain boundary embrittlement, ensuring nuts maintain ductility and mechanical integrity after long-term exposure above 600°C.

Fastener Performance

Incoloy 800HT Nuts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Incoloy 800HT Nuts per ASTM. Incoloy 800HT nuts achieve 620 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Nut SizeRecommended Torque (Nm)Clamp Load (kN)
M127032
M1617065
M20340105
M24590150
M301200245
M362100355
M423300510
M484800690
?? Anti-galling: Always use a nickel-based anti-seize compound on Incoloy 800HT nuts. Lubricated values assume K=0.15. Avoid copper-based anti-seize to prevent galvanic corrosion.

Industry Applications

Incoloy 800HT Nuts Applications — Industries & End Uses

Incoloy 800HT Nuts from RealBolt are specified across petrochemical furnaces, chemical processing, nuclear, and power generation where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
Incoloy 800HT nuts are the preferred choice for bolted joints in steam reformer outlet manifolds, furnace headers, and radiant coil supports, where resistance to high-temperature oxidation and carburization is critical for safe, long-term operation.
Used in superheater header connections, HRSG ductwork, and boiler tube sheet assemblies, Incoloy 800HT nuts maintain mechanical integrity and prevent stress rupture failures at elevated temperatures.
Specified for channel cover bolts, tube sheet fasteners, and closure hardware in heat exchangers and pressure vessels handling hot process streams, sulfur compounds, or ammonia-rich atmospheres.
Ideal for securing refractory anchors, tray supports, and structural connections in industrial ovens, kilns, and thermal processing equipment operating above 600°C.

Incoloy 800HT Nuts Standards & International Certifications

Incoloy 800HT 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
DIN 934 ISO 4032 ASME B18.2.2 IS 1364 IS 1367
Certifications
ISO 9001:2015PED 2014/68/EUNABL LabMTC 3.1 / 3.2

Buy Incoloy 800HT Nuts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Incoloy 800HT 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.
022-6743-7972
+91 90226 36025
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Answers for Buyers

Incoloy 800HT Nuts — Frequently Asked Questions

Browse expert answers to common questions about Incoloy 800HT Nuts from RealBolt — covering grade differences, ASTM B408/B425 standards, oxidation limits, acid resistance, sizes, and MTC documentation. Contact our technical team directly for project-specific guidance on Incoloy 800HT nuts selection and pricing.
Incoloy 800HT hex nuts are available to DIN 934 (metric hex), ISO 4032, and ASME B18.2.2 (inch hex and heavy hex). Thin pattern nuts per DIN 439 and ISO 4035 are also available. Custom thread forms (UNC, UNF, BSW) can be supplied on request with a typical lead time of 2-3 weeks.
Always use a nickel-based anti-seize compound (such as Molykote P-37 or Jet-Lube Pure Nickel) on Incoloy 800HT nuts to prevent galling and seizing at high temperatures. Avoid copper-based or zinc-based anti-seize, as these can cause galvanic corrosion with nickel alloys.
Yes – Incoloy 800HT nuts are engineered for continuous service up to 1100°C, with excellent resistance to oxidation, carburization, and stress rupture. They are widely specified for furnace, reformer, and superheater bolting where standard stainless steel nuts would fail.
No MOQ for standard sizes (M10-M36) held in stock – we supply from single pieces for urgent maintenance. Custom sizes or non-standard threads typically require a 10 kg minimum. Price breaks are available at 50, 200, and 500 pieces.

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
  • Canada
  • 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
  • Thailand
  • Vietnam
  • South Korea
  • Japan
  • Brazil