Heavy Hex Bolts
High-Strength Heavy Hex Bolts - Grades 8.8, 10.9, and 12.9
Professional heavy hex bolt factory from China for demanding structural applications
Product Overview
WT Fasteners specializes in manufacturing high-strength heavy hex bolts designed for the most demanding structural and industrial applications. Our heavy hex bolts are available in grades 8.8, 10.9, and 12.9, providing superior strength and reliability for critical connections in construction, infrastructure, and heavy machinery.
๐ง Key Features
- High-strength grades: 8.8, 10.9, and 12.9
- Heavy hex head design for maximum torque
- Precision threading and dimensions
- Superior material properties
- Excellent fatigue resistance
- Corrosion-resistant coating options
- Wide range of sizes and lengths
๐๏ธ?Applications
- Structural steel construction
- Bridge and infrastructure projects
- Heavy machinery assembly
- Industrial equipment connections
- Power transmission structures
- Mining and construction equipment
- Offshore and marine applications
- High-rise building construction
๐ Standards Compliance
- ISO Standards: ISO 898-1, ISO 4014, ISO 4017
- DIN Standards: DIN 931, DIN 933, DIN 6914
- ANSI Standards: ANSI B18.2.1, ANSI B18.6.3
- GB Standards: GB/T 5782, GB/T 5783
- ASTM: ASTM A325, ASTM A490, ASTM F3125
- EN Standards: EN 14399, EN 15048
โ?Strength Grades
- Grade 8.8: 800 MPa tensile, 640 MPa yield
- Grade 10.9: 1000 MPa tensile, 900 MPa yield
- Grade 12.9: 1200 MPa tensile, 1080 MPa yield
- ASTM A325: Structural bolt standard
- ASTM A490: High-strength structural bolt
- Custom Grades: Available upon request
Strength Grade Comparison
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Hardness (HRC) | Elongation (%) | Typical Applications |
|---|---|---|---|---|---|
| 8.8 | 800 | 640 | 23-34 | 12 | General structural, machinery |
| 10.9 | 1000 | 900 | 32-39 | 9 | High-stress structural, automotive |
| 12.9 | 1200 | 1080 | 39-44 | 8 | Critical structural, aerospace |
| A325 | 830 | 660 | 25-34 | 12 | Structural steel connections |
| A490 | 1040 | 940 | 33-39 | 9 | High-strength structural steel |
Dimensional Specifications (ISO 4014/DIN 931)
| Thread Size | Head Width (mm) | Head Height (mm) | Thread Length (mm) | Available Lengths (mm) | Weight (kg/100pcs) |
|---|---|---|---|---|---|
| M12 | 19 | 7.5 | 31 | 30-200 | 8.5 |
| M16 | 24 | 10 | 38 | 40-300 | 20.1 |
| M20 | 30 | 12.5 | 46 | 50-400 | 39.2 |
| M24 | 36 | 15 | 54 | 60-500 | 67.9 |
| M30 | 46 | 18.7 | 66 | 80-600 | 133.0 |
| M36 | 55 | 22.5 | 78 | 100-800 | 228.0 |
๐ฉ Material & Coating Options
Base Materials
- Carbon Steel (35CrMo, 42CrMo)
- Alloy Steel (SCM435, SCM440)
- Stainless Steel (A4-80, A4-100)
- Duplex Stainless Steel
- Inconel and Hastelloy (special order)
Surface Treatments
- Hot-dip Galvanized (HDG)
- Mechanical Galvanizing
- Zinc Electroplating
- Dacromet Coating
- Geomet Coating
- Black Oxide
- Plain Finish
Special Coatings
- PTFE (Teflon) Coating
- Epoxy Coating
- Ceramic Coating
- Phosphate Coating
- Nickel Plating
- Chrome Plating
- Custom Coating Solutions
Recommended Torque Values (Nm)
| Bolt Size | Grade 8.8 | Grade 10.9 | Grade 12.9 | Lubricated | Dry Condition |
|---|---|---|---|---|---|
| M12 | 85 | 120 | 145 | -15% | +20% |
| M16 | 210 | 300 | 360 | -15% | +20% |
| M20 | 410 | 590 | 710 | -15% | +20% |
| M24 | 710 | 1000 | 1200 | -15% | +20% |
| M30 | 1390 | 1950 | 2350 | -15% | +20% |
| M36 | 2400 | 3400 | 4100 | -15% | +20% |
โ?Quality Assurance Process
- Raw material chemical analysis and certification
- Heat treatment process monitoring and control
- Mechanical property testing (tensile, yield, hardness)
- Dimensional inspection with precision equipment
- Thread pitch and profile verification
- Surface finish and coating thickness testing
- Torque-tension relationship testing
- Fatigue testing for critical applications
- Final inspection and certification
๐จ Installation Best Practices
- Surface Preparation: Ensure clean, flat contact surfaces
- Hole Alignment: Verify proper hole alignment and clearance
- Washer Selection: Use appropriate washers for load distribution
- Torque Application: Apply torque gradually in multiple stages
- Sequence: Follow proper tightening sequence for multi-bolt connections
- Verification: Verify final torque values and bolt tension
- Documentation: Record installation data for quality control
๐งช Testing & Certification
Mechanical Testing
- Tensile strength testing
- Yield strength verification
- Elongation measurement
- Hardness testing (HRC/HV)
- Impact testing (when required)
Chemical Analysis
- Carbon content verification
- Alloy element analysis
- Sulfur and phosphorus limits
- Trace element detection
- Material traceability
Certifications
- ISO 9001:2015 Quality Management
- Material Test Certificates (MTC)
- Third-party inspection reports
- CE marking (when applicable)
- Custom certification requirements
Why Choose WT Heavy Hex Bolts?
๐ญ Advanced Manufacturing
State-of-the-art production facility with precision forging and heat treatment capabilities.
๐ฌ Technical Excellence
Expert metallurgical knowledge and engineering support for demanding applications.
๐ Consistent Quality
Rigorous quality control processes ensuring consistent mechanical properties and dimensions.
Get Your Heavy Hex Bolts Quote Today
Contact WT Fasteners for high-strength heavy hex bolt solutions and competitive factory pricing
๐ฑ WhatsApp: +86 159 2620 1780
Email: lipBolts@gmail.com
Website: wtbolts.com
