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M21 x 28mm Polycarbonate Hex Head Cap Screw | Corrosion Resistant

Expert Overview

This M21 x 28mm hex head cap screw is precision-engineered from high-performance polycarbonate. Offering exceptional strength-to-weight ratio and superior chemical resistance, it's ideal for environments where traditional metal fasteners fail.

StandardDIN 933
MaterialPolycarbonate
FinishPlain
GradeN/A
SizeM21
Length28mm
Head Width27mm

Detailed Engineering Specifications

Manufactured under strict quality controls, this M21 x 28mm hex head cap screw features a 27mm head width. Constructed from advanced polycarbonate, it exhibits excellent dielectric properties, high impact strength, and remarkable resistance to a wide range of acids, alkalis, and solvents. Its lightweight nature simplifies handling and reduces overall assembly weight, making it suitable for applications in chemical processing, electronics, and marine environments where corrosion is a critical concern.

🧊 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 the appropriate mating component with a pre-tapped M21 thread or a clearance hole for a nut. 2. Insert the polycarbonate hex head cap screw, ensuring full thread engagement. 3. Tighten using a standard socket wrench to the recommended torque specification, avoiding overtightening to prevent material deformation.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardDIN 933

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 screw, leading to thread stripping or head cracking.Use a torque wrench and adhere to the specified torque limits for polycarbonate fasteners to prevent damage.
Using in applications exceeding the maximum operating temperature range of polycarbonate.Verify the operational temperature requirements and ensure they fall within the known capabilities of polycarbonate materials for long-term integrity.

Common Applications

  • Chemical processing equipment
  • Electrical enclosure assemblies
  • Marine and offshore hardware
  • Lightweight structural components
  • Medical device manufacturing

⚠️ Engineering Warnings

  • Avoid exposure to UV radiation for prolonged periods unless specifically rated for outdoor use, as it may degrade material properties.
  • Do not use in applications requiring high-temperature resistance above the specified limit for polycarbonate (typically around 120°C).

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 enclosure assemblies, Marine and offshore hardware, Lightweight structural components, Medical device manufacturing.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 28mmAF27mm1/2"-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.