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M20 x 40mm 304 Stainless Steel Hex Cap Screw

Expert Overview

This M20 x 40mm hex head cap screw, crafted from premium 304 stainless steel, offers exceptional corrosion resistance and superior tensile strength for demanding fastening applications.

StandardDIN 933
Material304 Stainless Steel
FinishGalvanized
GradeN/A
SizeM20
Length40mm
Head Width17mm

Detailed Engineering Specifications

Engineered for reliability and performance, this M20 x 40mm hex head cap screw is manufactured from high-grade 304 stainless steel, renowned for its excellent resistance to corrosion and oxidation. The metric thread size ensures compatibility with metric tapped holes and nuts. Featuring a nominal diameter of M20 and a length of 40mm, the screw boasts a precisely machined head with a nominal width of 17mm, designed for optimal torque transfer with standard hex wrenches or sockets. Its robust construction makes it ideal for structural assemblies, machinery, marine environments, and food processing equipment where hygiene and durability are paramount.

🧊 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. Select the appropriate size and type of wrench or socket that matches the hex head dimensions. 2. Ensure the mating thread (in a tapped hole or nut) is clean and free of debris. 3. Engage the screw fully into the mating thread and tighten to the required torque specification, ensuring even pressure distribution.

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
Using the wrong size wrench, leading to head stripping.Always use a wrench or socket that correctly fits the 17mm hex head to prevent damage and ensure proper torque application.
Overtightening, causing thread damage or material fatigue.Adhere to the recommended torque specifications for the M20 thread size and the specific application to avoid overstressing the fastener and mating components.

Common Applications

  • Structural assembly in corrosive environments
  • Machinery and equipment manufacturing
  • Marine and offshore applications

⚠️ Engineering Warnings

  • Ensure compatibility with mating components (tapped holes or nuts) before installation.
  • Handle with care to avoid damage to threads or head during transport and 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 corrosive environments, Machinery and equipment manufacturing, Marine and offshore applications.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 40mmAF17mm1/2"-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.