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M21x71mm Polycarbonate Hex Head Cap Screw

Expert Overview

Engineered for demanding environments, this M21x71mm hex head cap screw offers exceptional strength and chemical resistance. Its polycarbonate composition ensures non-conductivity and durability.

StandardASME B18
MaterialPolycarbonate
FinishPlain
GradeN/A
SizeM21
Length71mm
Head Width11mm

Detailed Engineering Specifications

Purpose-built for heavy-duty applications, this M21x71mm hex head cap screw features a robust polycarbonate construction. With a head width of 11mm, it provides superior torque transfer and resistance to corrosive chemicals and electrical currents. Its high impact strength and temperature stability make it suitable for extreme operational conditions where metal fasteners might fail or introduce conductivity risks. This screw is designed for secure fastening in industrial machinery, marine equipment, and environments requiring non-sparking components.

🧊 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 threads are clean and free from debris. 2. Hand-thread the cap screw into the receiving component to avoid cross-threading. 3. Use an appropriate wrench or socket to tighten the screw to the specified torque, avoiding overtightening which can damage the polycarbonate.

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
Overtightening the polycarbonate screwUse a torque wrench set to the manufacturer's recommended torque value to prevent stripping threads or cracking the screw head.
Using metal tools that can damage the polycarbonate headEmploy non-marring tools or ensure a proper socket fit to prevent scratching or deforming the hex head.

Common Applications

  • Chemical processing equipment
  • Marine and offshore installations
  • Electrical enclosures and insulation

⚠️ Engineering Warnings

  • Not recommended for applications exceeding the material's specified temperature limits.
  • Avoid prolonged exposure to UV radiation unless specifically rated for outdoor use, as it may degrade the material 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, Polycarbonate made from?

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

Q: What are the main applications?

A: Chemical processing equipment, Marine and offshore installations, Electrical enclosures and insulation.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 71mmAF11mm1/2"-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.