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M21 x 145mm Polycarbonate Hex Head Cap Screw

Expert Overview

Engineered for demanding environments, this M21 x 145mm Hex Head Cap Screw offers superior chemical resistance and non-conductivity. Its polycarbonate construction ensures lightweight strength and excellent impact absorption for critical fastening applications.

StandardASTM A106
MaterialPolycarbonate
FinishBlack Oxide
GradeN/A
SizeM21
Length145mm
Head Width25mm

Detailed Engineering Specifications

Specified by design engineers worldwide, this M21 x 145mm Polycarbonate Hex Head Cap Screw features a nominal diameter of 21mm and a total length of 145mm, with a head width of 25mm. Manufactured from high-performance polycarbonate, it exhibits exceptional dielectric strength, excellent UV resistance, and superior corrosion resistance compared to metallic fasteners. Its thermoplastic nature allows for vibration dampening and a wide operating temperature range, making it ideal for applications where electrical insulation or non-sparking properties are paramount. Conforms to relevant ISO fastening standards.

🧊 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 appropriate tooling, ensuring compatibility with the hex head dimensions. 2. Align the screw with the pre-tapped hole or mating component, ensuring straight thread engagement. 3. Apply consistent, controlled torque to secure the assembly, avoiding over-tightening which can damage the polycarbonate material.

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

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 the screw, leading to material deformation or cracking.Use a torque wrench set to the manufacturer's recommended specification or consult design documentation for the appropriate torque value.
Using metallic tools that can scratch or damage the polycarbonate surface.Employ tools made from softer materials or ensure proper technique to prevent surface damage.

Common Applications

  • Electrical enclosures and control panels
  • Medical equipment assemblies
  • Corrosion-prone environments (e.g., chemical processing)

⚠️ Engineering Warnings

  • Polycarbonate can be susceptible to certain aggressive solvents; verify compatibility before use.
  • While impact resistant, avoid excessive direct impact that could compromise structural integrity.

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, Polycarbonate made from?

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

Q: What are the main applications?

A: Electrical enclosures and control panels, Medical equipment assemblies, Corrosion-prone environments (e.g., chemical processing).

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 145mmAF25mm1/2"-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.