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M20x66mm 304 Stainless Steel Hex Cap Screw | Fasteners

Expert Overview

Engineered for superior performance, this M20 x 66mm hex head cap screw is manufactured from high-grade 304 stainless steel, offering exceptional corrosion resistance and tensile strength for critical fastening applications.

StandardISO 9001
Material304 Stainless Steel
FinishGalvanized
GradeN/A
SizeM20
Length66mm
Head Width13mm

Detailed Engineering Specifications

Trusted by engineers across multiple sectors, this M20 x 66mm hex head cap screw delivers robust joining capabilities. Constructed from premium 304 stainless steel, it exhibits excellent resistance to corrosion, making it suitable for marine, chemical processing, and food & beverage environments. The robust hex head, with a nominal width of 13mm, allows for secure tightening with standard tooling. Its precise M20 thread pitch and 66mm length ensure reliable engagement in a wide array of structural and mechanical assemblies where durability and longevity are paramount. This fastener meets stringent industry standards for material integrity and mechanical properties.

🧊 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:Yes

Installation Procedure

1. Ensure the mating threads are clean and free of debris. 2. Hand-thread the cap screw into the receiving hole to verify alignment and prevent cross-threading. 3. Using the appropriate sized wrench or socket, tighten the cap screw to the specified torque value, ensuring a secure and stable connection.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardISO 9001

Mechanical Properties

Tensile Strength75,000 psi (515 MPa)
Yield Strength30,000 psi (205 MPa)
Elongation in 2 in.40% min
HardnessRockwell B95 max

Chemical Composition

Carbon (C)0.08% max
Chromium (Cr)18.0 - 20.0%
Nickel (Ni)8.0 - 10.5%
Manganese (Mn)2.00% max

Temperature & Environment Rating

Min Operating Temp
-320°F (-195°C)
Max Continuous Temp
1400°F (760°C)
Thermal Expansion
Typical for Material Class

Recommended Torque Values

Bolt SizeDry Torque (ft-lbs)Lubricated Torque (ft-lbs)
M20Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M20Varies by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedExcellent
Marine / SaltwaterGood
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Using the wrong size wrench, leading to head stripping.Always use a wrench or socket that precisely fits the 13mm hex head to prevent damage and ensure proper torque application.
Cross-threading the screw due to improper alignment.Carefully align the screw with the mating threads and hand-thread it initially to confirm correct engagement before applying torque.

Common Applications

  • Structural Frame Assembly
  • Heavy Machinery Fastening
  • Marine Equipment Construction

⚠️ Engineering Warnings

  • Always wear appropriate safety glasses during installation.
  • Ensure the material strength of the mating components is adequate for the applied load.

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, 304 Stainless Steel made from?

A: This Hex Head Cap Screw, 304 Stainless Steel is manufactured from 304 Stainless Steel.

Q: What are the main applications?

A: Structural Frame Assembly, Heavy Machinery Fastening, Marine Equipment Construction.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 66mmAF13mm1/2"-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.