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M21x34mm Brass Hex Head Cap Screw | Corrosion Resistant

Expert Overview

This M21x34mm brass hex head cap screw offers exceptional corrosion resistance and superior conductivity. Engineered for demanding environments, it provides reliable fastening for electrical, marine, and aesthetic applications.

StandardISO 9001
MaterialBrass
FinishGalvanized
GradeN/A
SizeM21
Length34mm
Head Width30mm

Detailed Engineering Specifications

Precision-manufactured to tight tolerances, this M21x34mm brass hex head cap screw features a nominal diameter of M21 and a length of 34mm. The hex head measures 30mm across flats, facilitating secure torque application with standard tooling. Composed of high-grade brass (typically UNS C36000 or equivalent), it exhibits excellent machinability, natural corrosion resistance against many chemicals and environments, and good electrical conductivity. This material is inherently non-magnetic, making it suitable for sensitive applications. Its ductility allows for some deformation without fracture, contributing to a robust joint.

🧊 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. Apply appropriate lubrication if required by the application or torque specifications. 3. Insert the cap screw and tighten to the specified torque using a calibrated wrench or driver, engaging the hexagonal head.

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)
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
Over-tightening brass fasteners, which can lead to galling or thread stripping.Adhere to recommended torque specifications for brass fasteners and use appropriate lubrication to prevent galling.
Using standard steel tools that can scratch or damage the brass surface, compromising aesthetics.Employ tools with soft jaws or protective coatings when working with brass fasteners to maintain surface integrity.

Common Applications

  • Electrical connections and grounding
  • Marine hardware and fittings
  • Decorative and architectural elements
  • Plumbing and valve components

⚠️ Engineering Warnings

  • Brass is a softer metal than steel; avoid excessive force that could damage threads or the fastener head.
  • While corrosion-resistant, brass can be susceptible to dezincification in certain aggressive environments; verify material compatibility for extreme conditions.

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: Electrical connections and grounding, Marine hardware and fittings, Decorative and architectural elements, Plumbing and valve components.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 34mmAF30mm1/2"-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.