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M12 x 31mm 304 Stainless Steel Hex Cap Screw

Expert Overview

Engineered for robust fastening, this M12 x 31mm hex cap screw is crafted from high-grade 304 stainless steel. Its superior corrosion resistance and strength make it ideal for critical joints in demanding environments.

StandardISO 9001
Material304 Stainless Steel
FinishPlain
GradeN/A
SizeM12
Length31mm
Head Width27mm

Detailed Engineering Specifications

Built to exacting engineering tolerances, this M12 x 31mm hex head cap screw features a nominal diameter of 12mm and a shank length of 31mm. The hexagonal head presents a wrenching surface with a measured width of 27mm, ensuring secure torque application. Fabricated from premium 304 stainless steel, it offers exceptional resistance to corrosion, oxidation, and a wide range of chemicals, making it suitable for outdoor, marine, and food-grade environments. The inherent tensile strength of 304 stainless steel ensures reliable load-bearing capacity in structural assemblies and mechanical equipment.

🧊 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 (27mm for this screw). 2. Ensure the mating threads are clean and free of obstructions. 3. Thread the screw into the component by hand to verify proper engagement and prevent cross-threading. 4. Tighten the screw to the specified torque using a calibrated torque wrench.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardISO 9001

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
Using the wrong size wrench, leading to cam-out and damaged screw heads.Always use a wrench or socket that precisely matches the 27mm head width of the screw.
Over-tightening, which can strip threads or compromise the integrity of the components being joined.Refer to engineering specifications or torque charts for the correct tightening torque for M12 fasteners in the specific application.
Using a steel screw in a corrosive environment, leading to premature rust and failure.Utilize 304 stainless steel for its superior corrosion resistance in environments prone to moisture or chemical exposure.

Common Applications

  • Structural steel connections
  • Machinery and equipment assembly
  • Outdoor and marine hardware installations

⚠️ Engineering Warnings

  • Ensure compatibility of mating threads and materials before installation.
  • Always wear appropriate personal protective equipment (PPE) during installation, including safety glasses.

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, Machinery and equipment assembly, Outdoor and marine hardware installations.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 31mmAF27mm1/2"-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.