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M20x81mm Brass Hex Head Cap Screw | Fastening & Joining

Expert Overview

This M20x81mm Brass Hex Head Cap Screw offers superior corrosion resistance and excellent electrical conductivity. Ideal for demanding industrial applications requiring reliable fastening.

StandardISO 9001
MaterialBrass
FinishPlain
GradeN/A
SizeM20
Length81mm
Head Width32mm

Detailed Engineering Specifications

A proven choice for industrial professionals, this M20x81mm Hex Head Cap Screw is engineered from high-grade brass, renowned for its excellent corrosion resistance, particularly in marine and chemical environments, and its non-sparking properties. The M20 thread provides robust mechanical strength, while the 81mm length offers significant grip and joining capability. With a substantial 32mm head width, standard hex drivers achieve optimal torque application, ensuring secure and reliable connections in a wide array of industrial assemblies and equipment.

🧊 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 mating threads are clean and free of debris. 2. Align the cap screw with the pre-drilled hole or tapped insert. 3. Hand-tighten to engage threads, then use an appropriate hex wrench to tighten to the specified torque. 4. Verify secure fastening without over-tightening.

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

Copper (Cu)60.0 - 63.0%
Zinc (Zn)Balance
Lead (Pb)2.5 - 3.7%

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
Using the wrong size wrench, leading to stripped hex heads.Always use a wrench that precisely fits the 32mm head width for optimal leverage and to prevent damage.
Over-tightening brass screws, which can lead to thread stripping or material fatigue.Adhere to recommended torque specifications for M20 brass screws; consult engineering drawings or material specifications.

Common Applications

  • Marine hardware and fittings
  • Electrical conductivity components
  • Corrosion-prone industrial machinery

⚠️ Engineering Warnings

  • Brass is a softer metal than steel; avoid excessive force during installation.
  • While corrosion-resistant, brass can be susceptible to dezincification in highly aggressive chemical 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, Brass made from?

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

Q: What are the main applications?

A: Marine hardware and fittings, Electrical conductivity components, Corrosion-prone industrial machinery.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 81mmAF32mm1/2"-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.