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M21x91mm Polycarbonate Hex Head Cap Screws

Expert Overview

Engineered for demanding environments, this M21x91mm polycarbonate hex head cap screw offers superior chemical resistance and electrical insulation. Its robust design ensures reliable fastening in corrosive and conductive applications.

StandardASTM A106
MaterialPolycarbonate
FinishGalvanized
GradeN/A
SizeM21
Length91mm
Head Width14mm

Detailed Engineering Specifications

Built to exacting engineering tolerances, this M21x91mm hex head cap screw is manufactured from high-performance polycarbonate. This thermoplastic polymer exhibits excellent impact strength, broad chemical resistance against acids, bases, and solvents, and superior dielectric properties, making it non-conductive and ideal for electrical insulation. The M21 thread standard ensures compatibility with standard metric nuts and tapped holes, while the 91mm length provides ample engagement. The 14mm head width allows for secure torque application with standard hex tools, minimizing risk of over-tightening and material damage.

🧊 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. Thread the M21x91mm polycarbonate hex head cap screw into the receiving component, applying steady, even torque. 3. Tighten to the recommended torque specification for polycarbonate fasteners to avoid stripping or cracking.

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 / ExposedExcellent
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Over-tightening the screw, leading to stripping or cracking the polycarbonate head.Utilize a torque wrench set to the manufacturer's recommended torque value for polycarbonate fasteners to prevent overstressing the material.
Using incompatible tools that may damage the hex head profile.Employ properly sized metric hex wrenches or sockets to engage the head fully and prevent slippage or deformation.

Common Applications

  • Electrical enclosures and equipment assembly
  • Chemical processing and laboratory fixtures
  • Corrosion-resistant structural components

⚠️ Engineering Warnings

  • Not suitable for high-temperature applications exceeding the material's glass transition temperature.
  • Avoid exposure to strong UV radiation which may degrade polycarbonate over extended periods unless specifically UV-stabilized.

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 equipment assembly, Chemical processing and laboratory fixtures, Corrosion-resistant structural components.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 91mmAF14mm1/2"-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.