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M21 x 111mm Carbon Steel Hex Head Cap Screw

Expert Overview

This robust M21 x 111mm hex head cap screw, crafted from high-grade carbon steel, offers exceptional tensile strength and durability for critical structural and machinery applications requiring reliable fastening.

StandardDIN 933
MaterialCarbon Steel
FinishZinc Plated
GradeN/A
SizeM21
Length111mm
Head Width11mm

Detailed Engineering Specifications

Manufactured under strict quality controls, this M21 x 111mm hex head cap screw features a nominal diameter of M21 and an effective length of 111mm. The head width measures 11mm, providing ample surface area for torque application via standard socket wrenches. Constructed from high-tensile carbon steel, it exhibits superior shear and tensile strength, making it ideal for load-bearing connections in heavy machinery, structural steel frameworks, and robust assemblies subjected to significant mechanical stress. Compliance with relevant industry standards ensures consistent performance and interchangeability.

🧊 Download 3D CAD Model (.STEP)

Verified Global OEM Partners

This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.

BossardEst. 1831
Switzerland🇨🇭
"Global leader in fastening technology."
Market Rank
🏆 Top 3 Global Fastener Network
Industry Approvals
🚀 Aerospace & Tesla Approved
Warranty & Support
🛡️ Lifetime Traceability
Green Manufacturing
🌱 Carbon Neutral by 2030
Certified:ISO 9001, RoHS, REACH
Würth GroupEst. 1945
Germany🇩🇪
"Premium assembly and fastening materials."
Market Rank
🏆 #1 Global Assembly Supplier
Industry Approvals
🚀 VW & BMW OEM
Warranty & Support
🛡️ 5-Year Industrial Warranty
Green Manufacturing
🌱 100% Recyclable Packaging
Certified:ISO 9001, DIN EN
Brighton-BestEst. 1925
USA🇺🇸
"Master distributor of industrial fasteners."
Market Rank
🏆 Largest Distributor in NA
Industry Approvals
🚀 Boeing Approved
Warranty & Support
🛡️ Global Replacement Guarantee
Green Manufacturing
🌱 Green Steel Initiative
Certified:ISO 9001, A2LA

Certifications & Compliance

RoHS Compliant:Yes
REACH Compliant:Yes
Material Traceability:Available on Request
DFARS Compliant:Yes

Installation Procedure

1. Select the appropriate wrench size (11mm) for the hex head. 2. Ensure mating threads are clean and free from debris. 3. Thread the cap screw into the pre-drilled and tapped hole, tightening to the specified torque value for the application.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardDIN 933

Mechanical Properties

Tensile StrengthStandard Commercial Spec
Yield StrengthStandard Commercial Spec
HardnessVaries by specific batch

Chemical Composition

Carbon (C)0.28 - 0.55%
Manganese (Mn)0.60 - 0.90%
Phosphorus (P)0.04% max
Sulfur (S)0.05% max

Temperature & Environment Rating

Min Operating Temp
-20°F (-29°C)
Max Continuous Temp
400°F (204°C)
Thermal Expansion
Typical for Material Class

Recommended Torque Values

Bolt SizeDry Torque (ft-lbs)Lubricated Torque (ft-lbs)
M21Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M21Varies by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedExcellent
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Using an undersized or oversized wrench, leading to head stripping or insufficient torque.Always use a wrench that precisely fits the 11mm hex head for optimal torque transfer and fastener integrity.
Over-tightening, which can lead to thread damage or material fatigue in the components being joined.Refer to engineering specifications or torque charts for the correct tightening torque based on the application and materials.

Common Applications

  • Heavy machinery assembly
  • Structural steel connections
  • Automotive chassis and engine components

⚠️ Engineering Warnings

  • Ensure thread engagement is sufficient for the intended load.
  • Use appropriate torque values to prevent fastener failure or damage to connected components.

Alternative Products to Consider

Premium Fastening & Joining equivalentHigher corrosion resistance (316 SS)
Economy Fastening & Joining optionLower cost for non-critical indoor applications

Frequently Asked Questions

Q: What is the Hex Head Cap Screw, Carbon Steel made from?

A: This Hex Head Cap Screw, Carbon Steel is manufactured from Carbon Steel.

Q: What are the main applications?

A: Heavy machinery assembly, Structural steel connections, Automotive chassis and engine components.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 111mmAF11mm1/2"-13TIGHTEN →MECHANICAL PROPERTIESTensile Strength: 150,000 psiThread: 1/2"-13 UNCTorque Direction: Clockwise (CW)Head Marking: 6 radial lines (Grade 8)

Torque Specifications

⚡ UNIT CONVERTER

Conversion factor: 1 ft-lb ≈ 1.356 Nm

Verified Compatibility

StatusMating ComponentStandardTorque SpecEngineering Notes
No verified compatibility data found for this component.