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M21x33mm Aluminum 6061 Hex Cap Screw

Expert Overview

This M21x33mm Hex Head Cap Screw, crafted from robust Aluminum 6061, offers superior corrosion resistance and a lightweight design. Ideal for applications requiring reliable joining without the weight penalty of steel.

StandardASME B18
MaterialAluminum 6061
FinishBlack Oxide
GradeN/A
SizeM21
Length33mm
Head Width12mm

Detailed Engineering Specifications

Precision-manufactured to tight tolerances, this M21x33mm Hex Head Cap Screw features a nominal diameter of M21, a length of 33mm, and a head width of 12mm. Constructed from Aluminum 6061, it exhibits excellent strength-to-weight ratio, good machinability, and high resistance to atmospheric corrosion. This material makes it particularly suitable for marine, aerospace, and automotive environments where weight reduction and environmental resilience are critical. The hex head design ensures secure torque application with standard tooling.

🧊 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:N/A

Installation Procedure

1. Ensure the mating threaded hole is clean and free from debris. 2. Insert the screw and engage the threads by hand for at least two full turns to prevent cross-threading. 3. Tighten the screw using an appropriate hex wrench or socket, applying torque gradually to the specified value for Aluminum 6061 fasteners to avoid over-stressing the material.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardASME B18

Mechanical Properties

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

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 Aluminum 6061 fasteners.Utilize a torque wrench to adhere to recommended torque specifications for Aluminum 6061 to prevent stripping threads or deforming the material.
Using standard steel torque values.Aluminum 6061 has a lower yield strength than steel; consult fastener torque charts specifically for aluminum alloys to ensure proper clamping force without damage.

Common Applications

  • Aerospace structural components
  • Automotive lightweight assemblies
  • Marine hardware and fixtures

⚠️ Engineering Warnings

  • Aluminum 6061 has a lower tensile strength than many steel alloys; select fasteners appropriately for load-bearing applications.
  • Avoid exposing Aluminum 6061 fasteners to aggressive chemicals or environments that could compromise their corrosion resistance over time.

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, Aluminum 6061 made from?

A: This Hex Head Cap Screw, Aluminum 6061 is manufactured from Aluminum 6061.

Q: What are the main applications?

A: Aerospace structural components, Automotive lightweight assemblies, Marine hardware and fixtures.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 33mmAF12mm1/2"-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.