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M21x119mm 304 Stainless Steel Hex Cap Screw

Expert Overview

Engineered for robust fastening, this M21x119mm hex head cap screw is crafted from high-grade 304 stainless steel. Its superior corrosion resistance and tensile strength ensure reliable performance in challenging environments.

StandardASTM A106
Material304 Stainless Steel
FinishZinc Plated
GradeN/A
SizeM21
Length119mm
Head Width28mm

Detailed Engineering Specifications

Precision-manufactured to tight tolerances, this M21x119mm hex head cap screw offers exceptional dimensional accuracy for secure and repeatable assembly. Constructed from premium 304 stainless steel, it exhibits excellent resistance to corrosion and oxidation, making it suitable for outdoor, marine, and chemical processing applications. The hex head design facilitates high torque application with standard tools, while the M21 thread pitch and 119mm length provide substantial clamping force and reach. The 28mm head width ensures proper tool engagement 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 size (28mm for this M21 screw). 2. Ensure threads on both the screw and the mating component are clean and free from debris. 3. Hand-thread the screw to start, then tighten with the wrench to the specified torque, avoiding over-tightening. 4. Verify secure engagement and proper alignment of the fastened components.

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)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)
M21Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M21Varies 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 or improper torque.Always use a wrench or socket that precisely fits the 28mm hex head for optimal engagement and torque application.
Cross-threading during installation, damaging both the screw and the receiving threads.Start threading by hand to ensure proper alignment before applying any tool torque.
Over-tightening, which can lead to thread stripping, fastener fatigue, or component damage.Adhere to recommended torque specifications for the application. If unsure, consult engineering documentation or a torque chart.

Common Applications

  • Structural assembly in corrosive environments
  • Marine and offshore equipment
  • Chemical processing plants
  • Food and beverage industry machinery
  • General industrial machinery and equipment

⚠️ Engineering Warnings

  • Ensure the 304 stainless steel is compatible with the specific environmental conditions to prevent galling or crevice corrosion in certain aggressive media.
  • Always use appropriate personal protective equipment (PPE) during installation and handling.

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 assembly in corrosive environments, Marine and offshore equipment, Chemical processing plants, Food and beverage industry machinery, General industrial machinery and equipment.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 119mmAF28mm1/2"-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.