Hot Dip Galvanized Bolts China Suppliers High Tensile Structural Fasteners Factory
Longze Heavy-Duty Hot Dip Galvanized Bolts are precision-engineered for high-load structural connections, providing unmatched stability for global infrastructure projects. Manufactured in our specialized Yongnian facility, these fasteners are designed to meet the rigorous demands of heavy steel structures, bridges, and industrial foundations, ensuring safety and structural integrity under extreme tension.
By integrating high-tensile materials with a superior Hot Dip Galvanized (HDG) coating of ≥55μm, our bolts offer a lifespan of over 30 years of rust protection, even in corrosive C5-M marine environments. Whether you require DIN, ISO, or ASTM standards, Longze delivers industrial-grade fasteners that combine mechanical strength with long-term environmental resilience.
Detailed Parameters
| Applicable Standards | DIN 933, DIN 931, ISO 4017, ASTM A325, ASTM A193 B7 | Diameter Range | M6 to M64 | 1/4" – 2-1/2" |
|---|---|---|---|
| Material Grades | Grade 8.8, 10.9, 12.9 | ASTM A325 Type 1 | Surface Finish | HDG (≥55μm), Zinc Plated, Dacromet, Geomet, Black Oxide |
| Tensile Strength | 800 MPa (8.8) to 125 ksi (ASTM A193 B7) | Yield Strength | 640 MPa (8.8) to 105 ksi (ASTM A193 B7) |
| Coating Thickness | Hot Dip Galvanized ≥55μm (Standard) | Response Time | 12-Hour Technical Quotation & MTC Support |
| Thread Types | Full Thread (DIN 933) & Half Thread (DIN 931) | Compliance | ISO 9001 Certified Quality Management |
Key Advantages
Extreme Corrosion Defense
HDG coating ≥55μm ensures 30+ years of rust protection in marine and industrial C5-M environments.
Rapid Technical Support
Get professional technical quotations and Material Test Certificates (MTC) within 12 hours.
High-Tensile Reliability
Available in Grades 8.8, 10.9, and ASTM A325/A490 for critical high-load structural nodes.
Embrittlement Control
Specialized baking process for Grade 10.9+ fasteners to prevent sudden hydrogen embrittlement fracture.
100% Traceability
Strict chemical verification for every heat number ensures raw material authenticity and safety.
Precision Over-Tapping
Custom thread tolerance management for HDG nuts to ensure zero seizing during on-site assembly.
Product Gallery
Management Platforms
Logistics Optimization
Sea-worthy reinforced cartons and fumigation-free pallets for secure global maritime transit.
Quality Control
ISO 9001 certified 5-step QC process from raw material intake to final dimensional check.
Assembly Matching
Complete sets provided with matching high-strength heavy hex nuts and structural washers.
Standard Compliance
Strict adherence to DIN/ISO/ASME head dimensions for a perfect tooling fit on site.
Thermal Resilience
Grade 10.9 and B7 materials maintain structural integrity under extreme temperature loads.
Technical Consulting
Expert guidance on selecting optimal materials based on project load and environmental factors.
Investment Return Comparison
| Material Grade | Performance Focus | Best Application |
|---|---|---|
| Grade 8.8 | Balanced Strength/Cost | General Steel Structures |
| Grade 10.9 | Superior Tensile Load | Bridges & Heavy Machinery |
| ASTM A325 | Structural Standardization | Structural Buildings |
| ASTM A193 B7 | Extreme Pressure/Heat | Oil & Gas, Flanges |
| HDG Coated | Long-term Durability | Marine & Outdoor Projects |
Frequently Asked Questions
Yes, full traceability is guaranteed. We provide detailed Mill Test Certificates (MTC) for every batch, covering chemical composition and mechanical properties.
Standard sizes are typically shipped from our Yongnian factory within 10–15 days, depending on the order volume.
For Grade 10.9 and above, we implement a specialized baking process immediately after plating to remove hydrogen and prevent sudden fracture.
A thickness of ≥55μm provides a robust sacrificial layer that prevents base metal oxidation, ensuring structural safety for 30+ years in harsh environments.
Yes, we provide complete assembly sets, including matching high-strength heavy hex nuts and structural washers to ensure a perfect and secure fit.
We recommend ASTM A325 or Grade 10.9 with Hot Dip Galvanization (HDG) to balance high load-bearing capacity with superior corrosion resistance.
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