Metric Grade 12.9 Screws Manufacturer & Exporter in India

Explore Metric Grade 12.9 Screws 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 12.9 Screws?

Metric Grade 12.9 screws are high-strength alloy steel fasteners manufactured to ISO 898-1 and EN 20898-1 standards. These screws are quenched and tempered to achieve a minimum tensile strength of 1220 MPa, making them ideal for critical bolted joints requiring maximum clamping force and resistance to shear and fatigue.

Grade 12.9 screws are widely specified in heavy machinery, automotive, and structural applications where superior mechanical performance is essential. Their black oxide or zinc-plated finish provides moderate corrosion resistance, and they are available in a wide range of metric sizes and thread forms.

Quick Specifications

MaterialAlloy Steel (Grade 12.9)
UNS NumberK1045 (typical)
DIN Number1.7225 (42CrMo4)
Material StandardISO 898-1 / EN 20898-1
Screw Standard (Metric)DIN 912 / ISO 4762 / DIN 7991
Screw Standard (Inch)ASME B18.3
Thread FormISO Metric (Coarse/Fine)
Diameter RangeM3-M72
Tensile Strength1220 MPa (177 ksi) min
Yield Strength1100 MPa (160 ksi) min
Hardness39-44 HRC
? All screws supplied with EN 10204 3.1 certification. Mechanical and chemical test reports available.

Complete the Fastener Set

Other Metric Grade 12.9 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Metric Grade 12.9 fastener range from certified alloy steel bar stock, including Metric Grade 12.9 Bolts, Metric Grade 12.9 Nuts, Metric Grade 12.9 Washers, Metric Grade 12.9 Studs, and Metric Grade 12.9 Threaded Rods. All Metric Grade 12.9 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.

Technical Data

Metric Grade 12.9 Screws Dimensions, Sizes & Thread Standards

Metric Grade 12.9 Screws are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 912 (hex socket head cap screw), DIN 7991 (countersunk), ISO 4762, and ISO 10642. Custom lengths in 5mm increments. Inch sizes available per ASME B18.3.

Socket Head Cap Screw Dimensions - Metric (DIN 912 / ISO 4762)

Size (M)Pitch (mm)Head Dia (mm)Head Ht (mm)Hex Socket (mm)Min L (mm)Max L (mm)
M30.55.53.02.5650
M40.77.04.03.0860
M50.88.55.04.01070
M61.010.06.05.01280
M81.2513.08.06.016100
M101.516.010.08.020120
M121.7518.012.010.025150
M162.024.016.014.030200
M202.530.020.017.035250
M243.036.024.019.040300
M303.545.030.022.050350
M364.054.036.027.060400
M424.563.042.032.070500
M485.072.048.036.080600

Dimensional & Material Standards

StandardCoversThread
DIN 912Socket head cap screwsMetric
DIN 7991Countersunk socket screwsMetric
ISO 4762Socket head cap screwsMetric
ISO 10642Countersunk socket screwsMetric
ASME B18.3Socket cap screws (inch)UNC/UNF
Material StandardRequirement
ISO 898-1Mechanical properties
EN 20898-1Mechanical properties
EN 10204 3.1Mill test certificate
ISO 4042Coating/plating

Material Chemistry

Metric Grade 12.9 Chemical Composition

Metric Grade 12.9 Screws 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 898-1 / EN 20898-1

ElementComposition (%)
Carbon (C)0.28-0.50
Manganese (Mn)0.50-1.50
Phosphorus (P)0.035 max
Sulfur (S)0.035 max
Silicon (Si)0.15-0.35
Chromium (Cr)0.90-1.20
Molybdenum (Mo)0.15-0.30
Nickel (Ni)0.25 max
Boron (B)0.003 max
? All heats verified by spectrometry. Full chemical test reports supplied with each batch.

Why Metric Grade 12.9 Alloy Composition Matters for Screws

High Carbon & Chromium — Strength & Wear Resistance
The elevated carbon and chromium content in Grade 12.9 screws enables high tensile strength and surface hardness, ensuring reliable performance in high-load and high-wear applications.
Molybdenum — Hardenability
Molybdenum improves hardenability and toughness, allowing Grade 12.9 screws to maintain strength even in large diameters and after heat treatment.
Low Phosphorus & Sulfur — Ductility
Strict limits on phosphorus and sulfur ensure ductility and resistance to brittle fracture, critical for safety in dynamic and impact-loaded joints.

Fastener Performance

Metric Grade 12.9 Screws Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Metric Grade 12.9 Screws per ASTM. Metric Grade 12.9 screws achieve 620 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Screw SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M6171413
M8413321
M10826634
M1214311449
M1635228298
M20690552154
M241200960223
M3023601888347
?? Anti-galling: Use molybdenum-based anti-seize for assembly. Lubricated values assume K=0.14. Do not use above 300°C without consulting engineering guidance.

Industry Applications

Metric Grade 12.9 Screws Applications — Industries & End Uses

Metric Grade 12.9 Screws 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.
Grade 12.9 screws are the standard for bolted joints in construction equipment, mining machinery, and industrial presses where maximum strength and fatigue resistance are required for safety-critical assemblies.
Used in engine assemblies, suspension systems, and drivetrain components, Metric Grade 12.9 screws provide the high clamping force and vibration resistance needed for performance and reliability in vehicles and racing applications.
Fastening of turbine hubs, gearboxes, and tower sections relies on Grade 12.9 screws for their high tensile strength and ability to withstand dynamic loads and cyclic stresses in harsh outdoor environments.
Metric Grade 12.9 screws are specified for rail track joints, bridge structures, and heavy steel frameworks where structural integrity and long-term durability are essential.

Metric Grade 12.9 Screws Standards & International Certifications

Metric Grade 12.9 Screws 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 9001:2015EN 10204 3.1PED 2014/68/EUCE Marking

Buy Metric Grade 12.9 Screws from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Metric Grade 12.9 Screws — 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 12.9 Screws — Frequently Asked Questions

Browse expert answers to common questions about Metric Grade 12.9 Screws 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 12.9 screws selection and pricing.
Metric Grade 12.9 screws are available to DIN 912 (socket head cap), DIN 7991 (countersunk), ISO 4762, ISO 10642, and ASME B18.3 (inch socket cap). Custom thread forms and lengths can be supplied on request, with full certification and traceability.
Use a molybdenum-based anti-seize compound (such as Molykote 1000 or Loctite LB 8012) on threads and under the head to prevent galling and ensure accurate torque. Avoid copper-based anti-seize if the screws are used in electrical assemblies or with aluminum parts.
Metric Grade 12.9 screws are recommended for use up to 300°C. For applications above this temperature, consult with engineering as the mechanical properties may degrade and alternative materials such as stainless steel or nickel alloys may be required.
Standard sizes (M6-M24) are available ex-stock with no MOQ-single pieces can be supplied for urgent needs. Custom sizes or finishes may require a minimum order of 10 kg or 100 pieces, with price breaks at higher 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