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M21x141mm Carbon Steel Hex Head Cap Screw

Expert Overview

This M21x141mm hex head cap screw, forged from high-grade carbon steel, offers exceptional tensile strength and durability. Its 13mm head width ensures secure torque application for critical structural and mechanical assemblies.

StandardISO 9001
MaterialCarbon Steel
FinishBlack Oxide
GradeN/A
SizeM21
Length141mm
Head Width13mm

Detailed Engineering Specifications

Specified by design engineers worldwide, this M21x141mm hex head cap screw is manufactured from premium carbon steel, offering superior tensile and shear strength for load-bearing applications. The M21 metric thread size ensures compatibility with standard M21 nuts and tapped holes. Its robust head geometry, with a 13mm width, allows for efficient torque transmission via standard hex wrenches, minimizing the risk of stripping. This fastener is engineered for applications demanding high clamping force and reliable joint integrity in environments subject to vibration or significant stress.

🧊 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. Ensure mating threads are clean and free of debris. 2. Apply appropriate lubricant or threadlocker if specified by design. 3. Hand-tighten the screw to seat the threads, then use a calibrated torque wrench to achieve the specified torque value.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardISO 9001

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 / ExposedModerate
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Over-tightening leading to thread stripping or fastener fracture.Utilize a calibrated torque wrench and adhere strictly to the design's specified torque values.
Using an incorrect size or type of wrench, resulting in head damage or insufficient torque.Employ a correctly sized hex socket or wrench that fits snugly on the head for optimal force application.

Common Applications

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

⚠️ Engineering Warnings

  • Ensure compatibility with M21 tapped holes or nuts.
  • Carbon steel is susceptible to corrosion; consider protective coatings for corrosive environments.

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 components.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 141mmAF13mm1/2"-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.