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M21x39mm Polycarbonate Hex Cap Screw - Heavy Duty

Expert Overview

Engineered for demanding environments, this M21x39mm Polycarbonate Hex Head Cap Screw offers exceptional strength and corrosion resistance. Its lightweight design makes it ideal for applications where weight and chemical inertness are critical.

StandardISO 9001
MaterialPolycarbonate
FinishAnodized
GradeN/A
SizeM21
Length39mm
Head Width14mm

Detailed Engineering Specifications

Purpose-built for heavy-duty applications, this M21x39mm Hex Head Cap Screw leverages the superior properties of polycarbonate. With a head width of 14mm, it provides robust clamping force while maintaining excellent impact resistance and a high tensile strength-to-weight ratio. Polycarbonate's inherent dielectric strength makes it suitable for electrical applications, and its resistance to a wide range of chemicals and solvents ensures long-term performance in corrosive environments. Ideal for structural assemblies, machine building, and applications requiring non-metallic fastening solutions.

🧊 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. Hand-thread the cap screw to the desired initial engagement. 3. Use an appropriate wrench or socket to tighten the cap screw to the specified torque, avoiding over-tightening.

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

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 polycarbonate screw, leading to thread stripping or material deformation.Always adhere to recommended torque specifications for polycarbonate fasteners. If unsure, start with a lower torque and incrementally increase while monitoring for signs of stress.
Using metal tools that can scratch or damage the polycarbonate surface, compromising its aesthetic or protective qualities.Utilize non-marring tools or apply protective tape to the tool head when tightening to prevent surface damage.

Common Applications

  • Chemical processing equipment
  • Electrical enclosures and busbars
  • Marine and offshore structures

⚠️ Engineering Warnings

  • Not suitable for applications exceeding the maximum service temperature of polycarbonate.
  • While resistant to many chemicals, compatibility testing is recommended for extreme or specialized chemical exposure.

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, Electrical enclosures and busbars, Marine and offshore structures.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 39mmAF14mm1/2"-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.