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M18 x 58mm 304 Stainless Steel Hex Cap Screw

Expert Overview

Engineered for superior performance, this M18 x 58mm hex head cap screw is crafted from robust 304 stainless steel. It offers exceptional corrosion resistance and high tensile strength for reliable fastening in critical applications.

StandardASME B18
Material304 Stainless Steel
FinishZinc Plated
GradeN/A
SizeM18
Length58mm
Head Width21mm

Detailed Engineering Specifications

Specified by design engineers worldwide, this M18 x 58mm hex head cap screw features a nominal diameter of 18mm and a length of 58mm, with a 21mm hex head width for standard tooling engagement. Manufactured from premium 304 stainless steel (austenitic chromium-nickel alloy), it provides excellent resistance to a wide range of corrosive environments, including atmospheric, chemical, and food processing applications. The material's inherent toughness and good ductility ensure reliable performance under significant tensile and shear loads, making it ideal for structural assemblies and equipment where longevity and integrity are 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 are clean and free of debris. 2. Hand-thread the cap screw into the receiving component to verify alignment and prevent cross-threading. 3. Tighten the cap screw using a calibrated torque wrench to the manufacturer's specified torque value for the M18 thread size and the connected materials.

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)
M18Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M18Varies 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 hex heads.Always use a properly sized wrench that fits snugly on the hex head to ensure maximum torque transfer and prevent damage.
Over-torquing the screw, causing thread stripping or component damage.Utilize a torque wrench and adhere to the recommended torque specifications for the specific application and materials being joined.
Installing in a corrosive environment without considering material compatibility.While 304 stainless steel offers good corrosion resistance, ensure it is appropriate for prolonged exposure to specific aggressive chemicals or saltwater environments; consider higher grades if necessary.

Common Applications

  • Structural steel framing and connections
  • Industrial machinery and equipment assembly
  • Marine and offshore applications requiring corrosion resistance

⚠️ Engineering Warnings

  • Ensure compatibility of mating threads and materials to prevent galvanic corrosion, especially in marine or high-humidity environments.
  • Always use appropriate personal protective equipment (PPE) during installation, including safety glasses and gloves.

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 framing and connections, Industrial machinery and equipment assembly, Marine and offshore applications requiring corrosion resistance.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 58mmAF21mm1/2"-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.