Metric Grade 8.8 Nuts Manufacturer & Exporter in India

Explore Metric Grade 8.8 Nuts Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.

-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 Metric Grade 8.8 Nuts?

Metric Grade 8.8 nuts are high-strength carbon steel fasteners manufactured to ISO 898-2 and EN 20898-2 standards. These nuts are typically paired with Grade 8.8 bolts and threaded rods, providing a minimum proof load of 580 MPa and designed for use in structural, automotive, and heavy machinery applications where reliable clamping force and vibration resistance are critical.

Grade 8.8 nuts are zinc plated or hot-dip galvanized for corrosion protection and are available in hex, heavy hex, and lock nut configurations. Their mechanical properties make them the industry standard for medium to high-stress bolted joints in metric assemblies worldwide.

Quick Specifications

MaterialCarbon Steel, quenched & tempered
Grade8.8
StandardISO 898-2 / EN 20898-2
Nut Standard (Metric)DIN 934 / ISO 4032 / DIN 439
Nut Standard (Inch)ASME B18.2.2 (equivalent)
Thread FormISO Metric (Coarse & Fine)
Diameter RangeM5-M64
Proof Load580 MPa min
Hardness21-32 HRC
FinishPlain, Zinc Plated, Hot-Dip Galvanized
? All nuts supplied with EN 10204 3.1 certification. Third-party inspection available on request.

Complete the Fastener Set

Other Metric Grade 8.8 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Metric Grade 8.8 fastener range from certified alloy steel bar stock, including Metric Grade 8.8 Bolts, Metric Grade 8.8 Screws, Metric Grade 8.8 Washers, Metric Grade 8.8 Studs, and Metric Grade 8.8 Threaded Rods. All Metric Grade 8.8 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.

Technical Data

Metric Grade 8.8 Nuts Dimensions, Sizes & Thread Standards

Metric Grade 8.8 Nuts are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 934 (hex), DIN 439 (thin), and ISO 4032. Custom thread pitches and finishes available. Inch equivalents per ASME B18.2.2 on request. All Metric Grade 8.8 nuts dimensions are verified against applicable DIN, ISO, and

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

Size (M)Pitch (mm)A/F (mm)Height (mm)
M50.884
M61.0105
M81.25136.5
M101.5178
M121.751910
M162.02413
M202.53016
M243.03619
M303.54624
M364.05529
M424.56534
M485.07538
M565.58545
M646.09551

Dimensional & Material Standards

StandardCoversThread
DIN 934Hex nuts, full heightMetric
DIN 439Hex nuts, thin (jam)Metric
ISO 4032Hex nuts, full heightMetric
ISO 4035Hex nuts, thinMetric
ASME B18.2.2Hex nuts (inch)UNC/UNF
Material StandardRequirement
ISO 898-2Mechanical properties
EN 20898-2Mechanical properties
EN 10204 3.1Mill test certificate
ISO 4042Electroplated coatings
ISO 10684Hot-dip galvanizing

Material Chemistry

Metric Grade 8.8 Nut Chemical Composition

Metric Grade 8.8 Nuts are produced from medium-carbon or alloy steel with carbon (0.15–0.55%), chromium, manganese, and boron additions controlled per ASTM and ISO 898-1. Carbon content and quench-and-temper heat treatment are the primary strength levers, delivering proof loads from 580 MPa (Class 8.8) to 970 MPa (Class 12.9).

Chemical Composition per ISO 898-2

ElementComposition (%)
Carbon (C)0.25-0.55
Manganese (Mn)0.50-1.65
Phosphorus (P)0.035 max
Sulfur (S)0.035 max
Boron (B)0.003 max
Iron (Fe)Balance
? All heats verified by spectrometry. Material traceability maintained from steel mill to finished nut.

Why Metric Grade 8.8 Alloy Composition Matters for Nuts

Carbon & Manganese — Strength & Ductility
The controlled carbon and manganese content ensures Grade 8.8 nuts achieve the required proof load and ductility, preventing brittle fracture under dynamic loads.
Low Phosphorus & Sulfur — Crack Resistance
Strict limits on phosphorus and sulfur minimize the risk of embrittlement and stress corrosion cracking, especially after heat treatment and surface finishing.
Boron — Hardenability
Trace boron additions improve hardenability during quenching, ensuring uniform mechanical properties throughout the nut body for reliable clamping force.

Fastener Performance

Metric Grade 8.8 Nuts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Metric Grade 8.8 Nuts per ASTM. Metric Grade 8.8 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 SizeProof Load (kN)Recommended Torque (Nm)
M816.125
M1025.549
M1236.685
M1666.9210
M20104410
M24151710
M302351400
M363402400
?? Assembly: Always use matching Grade 8.8 bolts. Lubricate threads for consistent preload. Torque values are for lightly oiled threads (K=0.14).

Industry Applications

Metric Grade 8.8 Nuts Applications — Industries & End Uses

Metric Grade 8.8 Nuts from RealBolt are specified across structural engineering, automotive, machinery, and pressure vessels where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
Automotive & Heavy Vehicles
Wind & Renewable Energy
Grade 8.8 nuts are the standard for steel structure connections, bridge assemblies, and pre-engineered building frames. Used with Grade 8.8 bolts for high-strength, vibration-resistant joints in beams, columns, and trusses.
Used in conveyor systems, presses, cranes, and agricultural machinery where reliable clamping and resistance to loosening under vibration are essential.

Metric Grade 8.8 Nuts Standards & International Certifications

Metric Grade 8.8 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, hardness test certificate, dimensional inspection report per ISO 4759, and proof load test records — available on request for all orders.
Standards
Certifications
ISO 9001:2015CE MarkingEN 10204 3.1PED 2014/68/EURoHS Compliant

Buy Metric Grade 8.8 Nuts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Metric Grade 8.8 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

Metric Grade 8.8 Nuts — Frequently Asked Questions

Browse expert answers to common questions about Metric Grade 8.8 Nuts from RealBolt — covering property class, tensile and proof load, galvanizing embrittlement risk, surface finishes, and dimensional certification. Contact our technical team directly for project-specific guidance on Metric Grade 8.8 nuts selection and pricing.
Metric Grade 8.8 nuts are manufactured to ISO 898-2 and EN 20898-2 for mechanical properties, with dimensional standards per DIN 934, ISO 4032, and DIN 439. They are compatible with ISO metric coarse and fine threads and can be supplied with EN 10204 3.1 certification.
Yes, but always use hot-dip galvanized Grade 8.8 nuts with galvanized bolts to ensure proper thread fit and corrosion resistance. Standard zinc-plated nuts may not fit correctly due to coating thickness differences. Specify ISO 10684 for hot-dip galvanized assemblies.
Grade 8.8 nuts can be supplied with zinc plating or hot-dip galvanizing for improved corrosion resistance. For highly corrosive or marine environments, consider stainless steel or apply additional protective coatings. Always match the finish to the application environment.
Standard sizes (M8-M24) are available ex-stock with no MOQ-single pieces can be supplied for urgent needs. Larger or special sizes may require a minimum order of 10 kg or 100 pieces. Bulk discounts apply for project quantities.

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