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M18 x 128mm Carbon Steel Hex Cap Screw - Industrial Grade

Expert Overview

Engineered for robust connections, this M18 x 128mm hex head cap screw is crafted from high-grade carbon steel. Featuring a 25mm head width for superior torque application, it's ideal for critical structural and mechanical assemblies requiring exceptional strength and durability.

StandardDIN 933
MaterialCarbon Steel
FinishPassivated
GradeN/A
SizeM18
Length128mm
Head Width25mm

Detailed Engineering Specifications

Trusted by engineers across multiple sectors, this M18 x 128mm hex head cap screw is manufactured from premium carbon steel, offering excellent tensile strength and durability for demanding industrial environments. The precise M18 thread specification ensures secure engagement with standard nuts and tapped holes, while the 128mm nominal length provides ample reach for varied assembly thicknesses. The 25mm hexagonal head is designed for optimal wrench grip, facilitating controlled tightening and maximizing torque transfer, crucial for applications in construction, heavy machinery, and automotive manufacturing where structural integrity is 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. Select the appropriate wrench size (25mm) for the hex head. 2. Ensure the mating thread or nut is clean and free of debris. 3. Insert the screw and engage the threads, tightening to the required torque specification for the application.

Equivalent Standards (Cross-Reference)

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

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
Using an undersized or incorrect wrench, leading to head stripping.Always use a properly sized 25mm wrench or socket to ensure maximum engagement and prevent damage to the hex head.
Over-tightening, which can lead to thread damage or screw fracture.Adhere to the recommended torque values for the specific application and material being fastened. Consult engineering drawings or torque charts.

Common Applications

  • Structural steel connections
  • Heavy machinery assembly
  • Automotive chassis and powertrain components

⚠️ Engineering Warnings

  • Carbon steel may be susceptible to corrosion in wet or chemically aggressive environments; consider protective coatings or alternative materials if necessary.
  • Always verify the load requirements and select fasteners with adequate tensile and shear strength for the intended 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: Structural steel connections, Heavy machinery assembly, Automotive chassis and powertrain components.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 128mmAF25mm1/2"-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.