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M20 x 126mm 304 Stainless Steel Hex Cap Screw | Heavy Duty

Expert Overview

Engineered for superior performance in challenging environments, this M20 x 126mm hex head cap screw is crafted from robust 304 stainless steel, offering exceptional corrosion resistance and tensile strength.

StandardDIN 933
Material304 Stainless Steel
FinishBlack Oxide
GradeN/A
SizeM20
Length126mm
Head Width34mm

Detailed Engineering Specifications

Purpose-built for heavy-duty applications, this M20 x 126mm hex head cap screw offers exceptional performance and durability. Constructed from premium 304 stainless steel, it exhibits superior resistance to corrosion and oxidation, making it ideal for use in harsh industrial, marine, and chemical processing environments. The M20 nominal diameter and 126mm length provide significant clamping force and structural integrity. Its robust hex head, measuring 34mm across flats, allows for high torque application with standard tooling, ensuring secure and reliable fastening. This fastener meets rigorous industry standards for strength and material composition.

🧊 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 to confirm proper engagement and alignment. 3. Tighten the cap screw to the manufacturer's recommended torque specification using calibrated tooling.

Equivalent Standards (Cross-Reference)

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

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
Over-tightening the cap screw, leading to thread stripping or bolt failure.Always adhere to the specified torque values for the application and use a torque wrench for precise control.
Using the wrong size wrench or tool, which can round the hex head and prevent proper tightening.Utilize a properly sized, high-quality wrench or socket that fits snugly onto the hex head.

Common Applications

  • Structural steel connections
  • Marine equipment assembly
  • Heavy machinery mounting

⚠️ Engineering Warnings

  • Always wear appropriate personal protective equipment (PPE) during installation.
  • Verify material compatibility with the intended environment to prevent premature corrosion.

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 steel connections, Marine equipment assembly, Heavy machinery mounting.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 126mmAF34mm1/2"-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.