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M18 x 18mm Carbon Steel Hex Cap Screw | Industrial Grade Fastener

Expert Overview

This M18 x 18mm Hex Head Cap Screw, crafted from high-grade carbon steel, offers exceptional strength and durability. Its precise dimensions and robust construction ensure secure and reliable fastening in demanding industrial environments.

StandardASTM A106
MaterialCarbon Steel
FinishBlack Oxide
GradeN/A
SizeM18
Length18mm
Head Width12mm

Detailed Engineering Specifications

A high-performance industrial component, this M18 x 18mm Hex Head Cap Screw is engineered for superior load-bearing capacity and resistance to shear and tensile stress. Constructed from high-carbon steel, it exhibits excellent tensile strength and a Rockwell hardness typically ranging from 25HRC to 32HRC, providing a robust solution for critical connections. The nominal diameter is M18, with a closely controlled length of 18mm and a standard head width of 12mm, ensuring compatibility with standard tooling and mating components in machinery, structural assemblies, and heavy 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. Ensure the mating threads are clean and free of debris. 2. Hand-tighten the cap screw to verify thread engagement. 3. Use a calibrated torque wrench to tighten the screw to the manufacturer's specified torque value, ensuring even pressure distribution.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardASTM A106

Mechanical Properties

Tensile StrengthStandard Commercial Spec
Yield StrengthStandard Commercial Spec
HardnessVaries by specific batch

Chemical Composition

Carbon (C)0.28 - 0.55%
Manganese (Mn)0.60 - 0.90%
Phosphorus (P)0.04% max
Sulfur (S)0.05% max

Temperature & Environment Rating

Min Operating Temp
-20°F (-29°C)
Max Continuous Temp
400°F (204°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 / ExposedModerate
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Over-tightening the screw, leading to thread stripping or fastener breakage.Always use a torque wrench and adhere to the recommended torque specifications for the fastener and application.
Using the wrong size or type of wrench, which can damage the hex head and lead to improper torque application.Utilize a properly sized hex socket or wrench that fits snugly onto the head of the cap screw.

Common Applications

  • Heavy machinery assembly
  • Structural steel construction
  • Automotive manufacturing
  • Industrial equipment maintenance

⚠️ Engineering Warnings

  • Always wear appropriate personal protective equipment (PPE), including safety glasses.
  • Ensure the fastener is rated for the specific environmental conditions and load requirements of the application.

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, Carbon Steel made from?

A: This Hex Head Cap Screw, Carbon Steel is manufactured from Carbon Steel.

Q: What are the main applications?

A: Heavy machinery assembly, Structural steel construction, Automotive manufacturing, Industrial equipment maintenance.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 18mmAF12mm1/2"-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.