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M20 x 20mm 304 Stainless Steel Hex Cap Screw

Expert Overview

Engineered for superior performance, this M20 x 20mm Hex Head Cap Screw is manufactured from high-grade 304 stainless steel. It offers exceptional corrosion resistance and tensile strength, making it a reliable choice for critical fastening applications.

StandardASTM A106
Material304 Stainless Steel
FinishAnodized
GradeN/A
SizeM20
Length20mm
Head Width35mm

Detailed Engineering Specifications

Specified by design engineers worldwide, this M20 x 20mm Hex Head Cap Screw offers a robust M20 thread diameter and a 20mm nominal length. The substantial 35mm hex head width ensures excellent torque transfer capability for secure assembly. Constructed from premium 304 stainless steel, it provides superior corrosion resistance against a wide range of environmental factors, including moisture and mild chemicals, and exhibits good mechanical properties. This makes it an ideal fastener for applications demanding durability and long-term reliability in marine, food processing, chemical, and general industrial environments.

🧊 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. Insert the cap screw into the designated hole, ensuring proper alignment. 3. Using an appropriate sized wrench or socket, tighten the cap screw to the recommended torque specification for the application.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardASTM A106

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 cam-out and damage to the hex head.Always use a wrench or socket that precisely fits the 35mm hex head to ensure secure engagement and prevent slippage.
Over-tightening the screw, which can strip the threads or deform the mating material.Consult engineering drawings or torque charts for the correct tightening specification. Apply torque gradually and consistently.

Common Applications

  • Structural assembly in marine environments
  • Food processing equipment and machinery
  • Chemical plant infrastructure
  • General industrial machinery and equipment

⚠️ Engineering Warnings

  • Ensure material compatibility with the surrounding environment to prevent galvanic corrosion if dissimilar metals are present.
  • Always use appropriate personal protective equipment (PPE) during installation.

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 assembly in marine environments, Food processing equipment and machinery, Chemical plant infrastructure, General industrial machinery and equipment.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 20mmAF35mm1/2"-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.