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M8 x 81mm 304 Stainless Steel Hex Cap Screw

Expert Overview

Engineered for robust connections, this M8 x 81mm hex head cap screw is crafted from premium 304 stainless steel. Delivering exceptional tensile strength and superior corrosion resistance, it ensures reliable performance in challenging conditions.

StandardASME B18
Material304 Stainless Steel
FinishGalvanized
GradeN/A
SizeM8
Length81mm
Head Width11mm

Detailed Engineering Specifications

Purpose-built for heavy-duty applications, this M8 x 81mm hex head cap screw features a precisely machined 11mm head width, facilitating secure torque application with standard tooling. Constructed from 304 stainless steel, it offers excellent resistance to rust, corrosion, and chemical degradation, making it ideal for outdoor environments, marine applications, and food processing equipment. The material's inherent toughness and ductility ensure consistent performance under significant mechanical stress, preventing premature failure. This screw meets stringent industry standards for load-bearing capacity and dimensional accuracy, guaranteeing interchangeability and dependable assembly in critical infrastructure and machinery.

🧊 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 tool (e.g., socket wrench, spanner) with a size matching the 11mm hex head. 2. Ensure mating threads are clean and free from debris. 3. Thread the screw into the designated fastener hole by hand initially to prevent cross-threading, then tighten to the required torque specification using the selected tool.

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)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)
M8Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M8Varies 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 stripped head.Always use a wrench or socket that precisely fits the 11mm hex head to ensure proper engagement and prevent damage.
Over-tightening, causing thread damage or material fatigue.Refer to torque charts for M8 stainless steel fasteners and use a torque wrench to achieve the specified tightness without excessive force.
Cross-threading the screw during initial engagement.Start threading the screw by hand for several turns to confirm it is engaging the mating threads correctly before applying tool torque.

Common Applications

  • Structural steel connections
  • Marine hardware and equipment
  • Outdoor machinery and enclosures
  • Chemical processing plants
  • Food and beverage manufacturing

⚠️ Engineering Warnings

  • Ensure compatibility with mating components' thread pitch and material.
  • For critical load-bearing applications, consult engineering specifications and material data sheets.

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 hardware and equipment, Outdoor machinery and enclosures, Chemical processing plants, Food and beverage manufacturing.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 81mmAF11mm1/2"-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.