Home > Fastening & Joining > Hex Head Cap Screw, 316 Stainless Steel

M9 x 55mm 316 Stainless Steel Hex Cap Screw

Expert Overview

This M9 x 55mm hex head cap screw, crafted from premium 316 stainless steel, offers superior corrosion resistance and exceptional tensile strength for demanding applications. Its robust design ensures secure and reliable fastening in harsh environments.

StandardASME B18
Material316 Stainless Steel
FinishZinc Plated
GradeN/A
SizeM9
Length55mm
Head Width24mm

Detailed Engineering Specifications

Engineered for reliability and performance, this M9 x 55mm hex head cap screw is manufactured from marine-grade 316 stainless steel, renowned for its outstanding resistance to pitting, crevice corrosion, and general corrosion, especially in chloride-rich environments. The M9 thread size ensures precise engagement with M9 tapped holes or nuts, while the 55mm length provides ample grip and clamping force for medium-duty assemblies. The generous 24mm head width facilitates high torque application with standard wrenches, ensuring a secure and lasting joint. Ideal for applications exposed to saltwater, chemicals, or elevated temperatures, where material integrity is 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. Ensure the mating threads (nut or tapped hole) are clean and free of debris. 2. Hand-thread the cap screw to verify proper alignment and prevent cross-threading. 3. Use a calibrated torque wrench to tighten the cap screw to the manufacturer's recommended torque specification for the M9 thread size and application.

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)
M9Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M9Varies by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedExcellent
Marine / SaltwaterExcellent
Chemical / AcidicGood

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Over-tightening the cap screw, leading to thread stripping or fastener failure.Always use a calibrated torque wrench and adhere to recommended torque values for the specific M9 thread size and application.
Using the wrong size wrench, which can round off the hex head and prevent proper tightening.Utilize a wrench that precisely fits the 24mm hex head to ensure optimal force transfer and prevent damage.

Common Applications

  • Marine hardware and fittings
  • Chemical processing equipment
  • Food and beverage processing machinery
  • Offshore oil and gas platforms
  • Architectural fixtures in corrosive environments

⚠️ Engineering Warnings

  • Ensure compatibility with mating materials to avoid galvanic corrosion, especially when used with dissimilar metals.
  • Inspect fasteners regularly for signs of wear or damage, particularly in highly corrosive environments.

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 fittings, Chemical processing equipment, Food and beverage processing machinery, Offshore oil and gas platforms, Architectural fixtures in corrosive environments.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 55mmAF24mm1/2"-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.