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M20x40mm 316 Stainless Steel Hex Head Cap Screw

Expert Overview

Engineered for superior performance, this M20x40mm hex head cap screw is crafted from high-grade 316 stainless steel, offering exceptional corrosion resistance and mechanical strength for critical applications.

StandardASTM A106
Material316 Stainless Steel
FinishBlack Oxide
GradeN/A
SizeM20
Length40mm
Head Width15mm

Detailed Engineering Specifications

Specified by design engineers worldwide, this M20x40mm hex head cap screw features a nominal diameter of M20 and a length of 40mm. The head width is precisely machined to 15mm, ensuring compatibility with standard tooling. Constructed from 316 stainless steel, it exhibits excellent resistance to pitting and crevice corrosion in aggressive environments, including saltwater and chemical processing. Its robust design provides high tensile strength and reliable load-bearing capabilities, making it ideal for marine, chemical, food processing, and outdoor infrastructure projects where durability and longevity 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 socket wrench or driver for the 15mm hex head. 2. Ensure the mating threads are clean and free from debris. 3. Thread the cap screw by hand to start, then use the wrench to tighten to the specified torque, avoiding over-tightening.

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)16.0 - 18.0%
Nickel (Ni)10.0 - 14.0%
Molybdenum (Mo)2.0 - 3.0%

Temperature & Environment Rating

Min Operating Temp
-320°F (-195°C)
Max Continuous Temp
1500°F (815°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 / SaltwaterExcellent
Chemical / AcidicGood

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Using the wrong size wrench, leading to stripped head corners.Always use a correctly sized socket or wrench that fully engages the hex head flats.
Cross-threading the screw, damaging both the screw and the receiving thread.Initiate threading by hand for at least two full rotations to confirm proper alignment before applying mechanical force.

Common Applications

  • Marine hardware and offshore structures
  • Chemical processing equipment
  • Food and beverage industry machinery
  • Architectural and construction projects in corrosive environments

⚠️ Engineering Warnings

  • Ensure proper torque is applied to avoid fastener failure or damage to mating components.
  • While 316 stainless steel offers excellent corrosion resistance, prolonged exposure to certain highly aggressive chemicals may still cause degradation.

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, 316 Stainless Steel made from?

A: This Hex Head Cap Screw, 316 Stainless Steel is manufactured from 316 Stainless Steel.

Q: What are the main applications?

A: Marine hardware and offshore structures, Chemical processing equipment, Food and beverage industry machinery, Architectural and construction projects in corrosive environments.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 40mmAF15mm1/2"-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.