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M21 x 11mm 304 Stainless Steel Hex Head Cap Screw

Expert Overview

Engineered for superior performance, this M21 x 11mm Hex Head Cap Screw is crafted from robust 304 stainless steel. Its precise dimensions and corrosion resistance make it a dependable choice for critical fastening applications.

StandardDIN 933
Material304 Stainless Steel
FinishPlain
GradeN/A
SizeM21
Length11mm
Head Width30mm

Detailed Engineering Specifications

Built to exacting engineering tolerances, this M21 Hex Head Cap Screw boasts a nominal diameter of M21 and a compact length of 11mm, with a substantial 30mm head width for secure torque application. Constructed from premium 304 stainless steel, it offers excellent corrosion resistance, crucial for environments exposed to moisture or chemicals, and provides reliable tensile strength. The hex drive ensures efficient and secure tightening with standard tools, making it suitable for applications requiring a low-profile, high-strength fastening solution.

🧊 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 are clean and free from debris. 2. Insert the cap screw into the designated hole. 3. Tighten the cap screw to the manufacturer's recommended torque specification using an appropriate wrench.

Equivalent Standards (Cross-Reference)

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

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
Over-tightening leading to stripped threads or fastener fracture.Always use a calibrated torque wrench and adhere to recommended torque values for the specific application and mating materials.
Using the wrong tool size for the hex head, resulting in cam-out and fastener damage.Utilize a properly sized hex bit or wrench that fits snugly into the head recess to ensure maximum engagement and prevent slippage.

Common Applications

  • Machinery and equipment assembly
  • Structural components in corrosive environments
  • Automotive and marine applications

⚠️ Engineering Warnings

  • Ensure compatibility with mating materials to prevent galvanic corrosion.
  • Do not exceed the shear or tensile strength limits of the fastener.

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: Machinery and equipment assembly, Structural components in corrosive environments, Automotive and marine applications.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 11mmAF30mm1/2"-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.