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M20 x 78mm 316 Stainless Steel Hex Cap Screw

Expert Overview

Engineered for demanding environments, this M20 x 78mm Hex Head Cap Screw is forged from premium 316 stainless steel. Its superior corrosion resistance and robust design ensure reliable, long-lasting fastening in aggressive conditions.

StandardASME B18
Material316 Stainless Steel
FinishGalvanized
GradeN/A
SizeM20
Length78mm
Head Width31mm

Detailed Engineering Specifications

Precision-manufactured to tight tolerances, this M20 x 78mm hex head cap screw offers exceptional performance. Constructed from 316 stainless steel, it boasts superior resistance to pitting, crevice corrosion, and general corrosion, especially in chloride-rich environments. The material's high tensile strength ensures a secure and durable connection, making it suitable for critical applications. The M20 thread pitch provides significant load-bearing capacity, while the 78mm length allows for versatile use in varying material thicknesses. The 31mm head width ensures adequate bearing surface for torque application and load distribution.

🧊 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 wrench or socket for the M20 hex head. 2. Ensure mating surfaces are clean and free of debris. 3. Thread the cap screw into the designated tapped hole or nut, applying consistent torque as per design specifications.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardASME B18

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 standard stainless steel (e.g., 304) in highly corrosive environments.Always specify 316 stainless steel for marine, chemical, or saltwater applications due to its superior molybdenum content for enhanced corrosion resistance.
Over-tightening the cap screw, leading to thread stripping or material fatigue.Adhere to recommended torque values based on the material being fastened and the screw's specifications to prevent damage and ensure optimal performance.

Common Applications

  • Marine hardware and shipbuilding
  • Chemical processing equipment
  • Food and beverage industry machinery
  • Offshore oil and gas components

⚠️ Engineering Warnings

  • Ensure compatibility with mating components to prevent galvanic corrosion.
  • Always use thread-locking compounds when specified for critical applications to prevent loosening due to vibration.

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 shipbuilding, Chemical processing equipment, Food and beverage industry machinery, Offshore oil and gas components.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 78mmAF31mm1/2"-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.