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Monel 400 Bolts Manufacturer & Exporter in India

Explore Monel 400 Bolts Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.
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-200

Min Temp

550

Max Temp

🌡

550

Suitable for continuous service up to approximately 550°C under typical operating conditions.

⚡

550

Typical tensile strength around 550 MPa depending on product form and heat treatment.

🛡

Excellent

Excellent corrosion resistance in a wide range of industrial environments.

⚖

8.8

Typical density is approximately 8.8 g/cm³.

Product Overview

What are Monel 400 Bolts?

Monel 400 bolts are nickel-copper alloy fasteners manufactured from UNS N04400 bar stock conforming to ASTM B164. The alloy’s single-phase solid-solution structure – comprising 63-70% nickel and 28-34% copper – delivers a minimum tensile strength of 483 MPa in the annealed condition, with excellent toughness retained at cryogenic temperatures down to -196°C.

Monel 400 bolts resist corrosion in seawater, hydrofluoric acid, and alkaline media at a level unmatched by any standard stainless steel grade. They are specified under NACE MR0175/ISO 15156 for sour-service applications and are widely used in marine, chemical processing, and offshore environments where chloride stress corrosion cracking of austenitic stainless steel is a documented failure mode.

Quick Specifications

MaterialMonel 400
UNS NumberN04400
DIN Number2.4360
Material StandardASTM B164
Bolt Standard (Metric)DIN 931 / DIN 933 / ISO 4014
Bolt Standard (Inch)ASME B18.2.1
Thread FormISO Metric / UNC / UNF
Diameter RangeM6-M100 / ¼"-4"
Tensile Strength483 MPa (70 ksi) min
Yield Strength172 MPa (25 ksi) min
HardnessMax 35 HRC / 241 HB
? All material certified by NABL-accredited laboratory. PMI available on request.

Complete the Fastener Set

Other Monel 400 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Monel 400 fastener range from certified nickel-copper alloy bar stock, including Monel 400 Nuts, Monel 400 Screws, Monel 400 Washers, Monel 400 Studs, and Monel 400 Threaded Rods. All Monel 400 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
Monel 400 Nuts
Monel 400 Screws
Monel 400 Washers
Monel 400 Studs
Monel 400 Threaded Rods

Technical Data

Monel 400 Bolts Dimensions, Sizes & Thread Standards

Monel 400 Bolts are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 931 (partial thread) / DIN 933 (full thread) / ISO 4014. Custom lengths in 5mm increments. Inch dimensions available per ASME B18.2.1. All Monel 400 bolts dimensions are verified against applicable DIN, ISO, and ASME

Hex Bolt Dimensions - Metric (DIN 931 / ISO 4014)

Size (M)Pitch (mm)A/F (mm)Head Ht (mm)Min L (mm)Max L (mm)
M61.0104.010200
M81.25135.312250
M101.5176.416300
M121.75197.520400
M162.02410.025500
M202.53012.530600
M243.03615.040600
M303.54618.750800
M364.05522.5601000
M424.56526.0801000
M485.07530.01001200
M565.58535.01201500
M646.09540.01402000
M726.010545.01602000
M806.011550.01802500
M1006.014563.02003000

Dimensional & Material Standards

StandardCoversThread
DIN 931Hex bolts, partial threadMetric
DIN 933Hex bolts, full threadMetric
ISO 4014Hex head screws, partialMetric
ISO 4017Hex head screws, fullMetric
ASME B18.2.1Hex & heavy hex boltsUNC/UNF
ASME B16.5Stud bolts for flangesUNC
MSS SP-75Stud bolts, high-pressureUNC
Material StandardRequirement
ASTM B164Bar/rod - UNS N04400
ASTM F468Fastener mechanical properties
NACE MR0175Sour service =35 HRC
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Monel 400 Chemical Composition

Monel 400 Bolts are produced from a nickel-copper alloy containing 63% minimum nickel and 27–34% copper, with elemental limits certified to ASTM. The nickel base delivers seawater and HF acid immunity; copper additions enhance ductility; and in Monel K500, aluminium and titanium additions enable age-hardened strength above 896 MPa.

Chemical Composition per ASTM B164

ElementComposition (%)
Nickel (Ni)63.0% min
Copper (Cu)28.0-34.0%
Iron (Fe)2.5% max
Manganese (Mn)2.0% max
Carbon (C)0.30% max
Silicon (Si)0.50% max
Sulfur (S)0.024% max
? All heats verified by NABL-accredited spectrometry. PMI available on request.

Why Monel 400 Alloy Composition Matters for Bolts

Ni (63% min) — Chloride Stress Corrosion Immunity
The high nickel content gives Monel 400 complete immunity to chloride-induced stress corrosion cracking — the primary failure mode of 316L stainless steel bolts in marine and offshore environments. Bolt threads and bearing surfaces remain intact even under sustained tensile load in seawater.
Cu (28–34%) — Hydrofluoric Acid Resistance
The nickel-copper ratio makes Monel 400 one of the very few metallic alloys that resists anhydrous and aqueous hydrofluoric acid across a wide concentration range. This makes it the default bolt material for HF alkylation unit flanges and acid handling equipment in refineries.
Low Carbon (0.30% max) — Weld Zone Integrity
The controlled carbon ceiling limits carbide precipitation in the heat-affected zone during welding. Monel 400 bolts can be incorporated into welded assemblies without sensitisation risk, maintaining full corrosion resistance at the thread root and shank without post-weld heat treatment in most applications.

Fastener Performance

Monel 400 Bolts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Monel 400 Bolts per ASTM. Monel 400 bolts achieve 550 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Tightening Torque Reference - Monel 400 Bolts

Bolt SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M12524219
M1612510046
M2024519673
M24425340106
M30850680168
M3614801184244
M4223601888336
M4835002800442
?? 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-copper alloys - it introduces galvanic incompatibility and accelerates thread corrosion.

Industry Applications

Monel 400 Bolts Applications — Industries & End Uses

Monel 400 Bolts from RealBolt are specified across marine, HF alkylation, desalination, and chemical processing where excellent corrosion resistance and 550 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples. Select an industry below to see specific Monel 400 bolts application details and RealBolt stock availability.
Monel 400 hex bolts and stud bolts are the preferred fastener for offshore platform structural connections, splash-zone pipe supports, seawater cooling system flanges, and propeller shaft couplings. The alloy’s immunity to chloride pitting and crevice corrosion under bolt heads eliminates the need for protective coatings in permanently immersed or tidal-zone applications. Compliant with NORSOK MDS D47.
Monel 400 stud bolt sets are specified for hydrofluoric acid alkylation unit flanges, sour gas gathering system connections, and wellhead equipment where H2S partial pressure and chloride content exceed the limits of duplex stainless steel. Compliant with NACE MR0175/ISO 15156 at hardness =35 HRC. Listed in Shell DEP and ExxonMobil EMSP.
Flange stud bolt sets for sulfuric acid dilution systems, hydrochloric acid storage vessel nozzles, and phosphoric acid reactor closures where austenitic stainless steel suffers accelerated corrosion. Monel 400 bolts maintain full mechanical integrity across acid concentrations from dilute to near-anhydrous at ambient and moderately elevated temperatures.
Monel 400 bolts are used in multi-stage flash (MSF) and reverse osmosis (RO) desalination plant heat exchanger channel covers, brine heater flanges, and high-pressure membrane housing connections. The alloy’s resistance to hot brine and chlorinated seawater at temperatures up to 120°C makes it the standard fastener material in Middle East desalination projects.

Monel 400 Bolts Standards & International Certifications

Monel 400 Bolts 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, Lloyds Register or DNV certification, NACE MR0175, and PMI (XRF) reports — available on request for all orders.
Standards
DIN 931 DIN 933 ISO 4014 ISO 4017 ASME B18.2.1 BS 1768 BS 3692 IS 1364 IS 1367
Certifications
ISO 9001:2015NACE MR0175NABL LabPED 2014/68/EUMTC 3.1 / 3.2

Buy Monel 400 Bolts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Monel 400 Bolts — 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.
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Answers for Buyers

Monel 400 Bolts — Frequently Asked Questions

Browse expert answers to common questions about Monel 400 Bolts from RealBolt — covering Monel 400 vs K500 selection, seawater and HF acid resistance, ASTM B164/B865, sizes, and MTC documentation. Contact our technical team directly for project-specific guidance on Monel 400 bolts selection and pricing.
Monel 400 hex bolts are manufactured to DIN 931 (metric partial thread), DIN 933 (metric full thread), ISO 4014/4017, and ASME B18.2.1 for inch hex and heavy hex configurations. Stud bolts for flange applications are produced per ASME B16.5 and MSS SP-75. Non-standard thread forms including BSW, BSF, and BSPP are available on request with a typical lead time of 15 working days from order confirmation.
Yes – Monel 400 is one of the few metallic alloys with proven resistance to both anhydrous and aqueous hydrofluoric acid across a wide concentration range. It is the standard bolt material for HF alkylation unit flanges in petroleum refineries and for acid handling equipment in chemical plants. The alloy should not be used in aerated HF solutions or in contact with mercury, which causes liquid metal embrittlement. Always consult your process engineer for specific concentration and temperature limits.
Yes – Monel 400 performs exceptionally in seawater, resisting pitting, crevice corrosion, and biofouling-induced attack under bolt head bearing surfaces and beneath washers. It is listed in NORSOK MDS D47 for offshore structural fasteners and is widely used in splash-zone and fully immersed marine connections. Unlike stainless steel, Monel 400 does not suffer chloride stress corrosion cracking under sustained tensile load in seawater environments.
Use a nickel-based anti-seize compound such as Molykote P-37, Bostik Never-Seez Pure Nickel, or Jet-Lube KOPR-KOTE Pure Nickel. Apply to the thread flanks and nut bearing face, and reduce applied torque by approximately 20% compared to dry assembly values. Avoid copper-based anti-seize on Monel 400 – the copper content of the paste combined with the nickel-copper alloy substrate can create localised galvanic cells that accelerate corrosion at the thread interface, particularly in wet or immersed service.

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