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M20 x 129mm Carbon Steel Hex Cap Screw | Industrial Grade

Expert Overview

This M20 x 129mm Hex Head Cap Screw, constructed from robust carbon steel, offers exceptional tensile strength and durability. Engineered for secure and reliable fastening in critical industrial applications.

StandardDIN 933
MaterialCarbon Steel
FinishPlain
GradeN/A
SizeM20
Length129mm
Head Width16mm

Detailed Engineering Specifications

A proven choice for industrial professionals, this M20 x 129mm Hex Head Cap Screw is manufactured from high-grade carbon steel, ensuring superior tensile strength and shear resistance for demanding applications. The M20 nominal diameter, coupled with a 129mm length, provides ample engagement for secure connections. Its 16mm hexagonal head width allows for high torque application with standard tooling, making it ideal for heavy machinery, structural assembly, and general engineering where reliability is paramount.

🧊 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 anti-seize compound if specified for the application. 3. Thread the cap screw into the designated hole, ensuring smooth engagement. 4. Tighten to the recommended torque specification using a calibrated torque wrench.

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)
M20Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M20Varies 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 material deformation.Always adhere to the manufacturer's recommended torque specifications for the specific application and materials being joined.
Using a fastener with insufficient length for proper thread engagement.Verify that the screw length provides at least 1.5 to 2 full threads beyond the point of engagement with the mating component.

Common Applications

  • Heavy Machinery Assembly
  • Structural Steel Connections
  • Industrial Equipment Manufacturing

⚠️ Engineering Warnings

  • Ensure the carbon steel material is suitable for the operating environment to prevent corrosion.
  • Always use appropriate personal protective equipment (PPE) during installation, including safety glasses and gloves.

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, Industrial Equipment Manufacturing.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 129mmAF16mm1/2"-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.