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Brass Hex Head Cap Screw M21 x 127mm - Corrosion Resistant

Expert Overview

Engineered for exceptional corrosion resistance and non-magnetic properties, this M21 x 127mm brass hex head cap screw is ideal for harsh industrial settings where galvanic corrosion is a concern.

StandardASTM A106
MaterialBrass
FinishGalvanized
GradeN/A
SizeM21
Length127mm
Head Width8mm

Detailed Engineering Specifications

Designed for demanding industrial environments, this M21 x 127mm hex head cap screw is fabricated from high-quality brass, offering superior resistance to corrosion, tarnishing, and a wide range of chemicals. Its non-magnetic properties make it suitable for sensitive electrical and electronic assemblies. The M21 thread standard ensures robust engagement, while the 127mm length provides ample reach for various assembly requirements. The 8mm head width is optimized for standard wrench engagement, facilitating secure tightening and loosening during maintenance or assembly processes.

🧊 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. Select an appropriately sized wrench that fits the 8mm hex head. 2. Align the M21 threads of the cap screw with the corresponding tapped hole or nut. 3. Apply steady, even torque to the hex head to engage the threads. 4. Continue tightening until the desired clamping force is achieved, avoiding overtightening which can damage threads.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardASTM A106

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)
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 excessive force, leading to thread stripping or fastener breakage.Utilize a torque wrench to ensure the screw is tightened to the manufacturer's recommended torque specification, or apply firm, consistent pressure without over-exertion.
Cross-threading the screw by not properly aligning the threads before applying torque.Initiate thread engagement by hand for several turns to confirm proper alignment before using a wrench. If resistance is felt, back out and re-align.

Common Applications

  • Marine hardware and fittings
  • Chemical processing equipment
  • Electrical enclosures and connectors
  • Food processing machinery
  • Plumbing and HVAC systems

⚠️ Engineering Warnings

  • Brass is a relatively soft material; avoid using impact wrenches which can damage the head or threads.
  • While brass offers good corrosion resistance, it may not be suitable for all highly aggressive chemical environments. Consult material compatibility charts.

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, Chemical processing equipment, Electrical enclosures and connectors, Food processing machinery, Plumbing and HVAC systems.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 127mmAF8mm1/2"-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.