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M12 x 129mm 304 Stainless Steel Hex Cap Screw

Expert Overview

This M12 x 129mm hex head cap screw, crafted from premium 304 stainless steel, offers superior corrosion resistance and robust tensile strength. Engineered for reliability in diverse environments.

StandardASME B18
Material304 Stainless Steel
FinishGalvanized
GradeN/A
SizeM12
Length129mm
Head Width28mm

Detailed Engineering Specifications

Trusted by engineers across multiple sectors, this M12 x 129mm hex head cap screw is manufactured from high-grade 304 stainless steel, renowned for its excellent corrosion resistance in acidic and chloride-laden environments. With a nominal diameter of M12 and a total length of 129mm, it features a precisely machined hex head with a width of 28mm for secure torque application. The material's inherent strength and durability make it ideal for structural assemblies, outdoor equipment, marine applications, and food processing machinery where hygiene and longevity are paramount. This fastener meets stringent industrial standards for load-bearing capacity and thread integrity.

🧊 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 mating threads are clean and free of debris. 2. Apply appropriate lubricant or anti-seize compound if required by the application environment. 3. Use a calibrated torque wrench to tighten the screw to the manufacturer's specified torque value for the M12 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)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)
M12Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M12Varies 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
Over-torquing the fastener, leading to thread stripping or material fatigue.Always use a calibrated torque wrench and adhere to specified torque values for the fastener size and application.
Using a standard steel screw in a corrosive environment, resulting in premature rust and failure.Select 304 stainless steel fasteners for applications exposed to moisture, chemicals, or marine conditions.

Common Applications

  • Structural steel connections
  • Outdoor equipment and machinery
  • Marine and coastal installations
  • Food processing and pharmaceutical equipment

⚠️ Engineering Warnings

  • Ensure thread compatibility with the mating component.
  • Avoid using abrasive cleaning agents on stainless steel surfaces to maintain corrosion resistance.

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, Outdoor equipment and machinery, Marine and coastal installations, Food processing and pharmaceutical equipment.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 129mmAF28mm1/2"-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.