The Zinc Plated Hex Bolt is a versatile, corrosion-resistant fastening solution extensively utilized across general machinery, structural framing, electrical enclosure support, and commercial construction projects. Manufactured from high-grade carbon steel (Q195, Q235, or 45# steel) and finished with an advanced electro-galvanizing coating, this fastener provides superior anti-rust protection, clean silver aesthetic finish, and outstanding installation reliability in accordance with international ISO standards.
Technical Specifications of Zinc Plated Hex Bolt
We produce electro-galvanized hex bolts in both Class 4.8 (low carbon steel) for standard structural assemblies and Grade 8.8 (quenched and tempered medium carbon steel) for high-tensile load applications. The electro-plated zinc layer creates a protective barrier preventing surface oxidation and red rust formation.
| Parameter | Class 4.8 Zinc Plated | Grade 8.8 High Tensile Zinc Plated |
|---|---|---|
| Core Material | Low Carbon Steel (Q195 / Q235) | Medium Carbon Steel (45# / 40Cr) |
| Tensile Strength | 400 N/mm² (Nominal) | 800 N/mm² (Nominal) |
| Zinc Layer Thickness | 5 µm – 12 µm Electro-Galvanized | 5 µm – 15 µm (With Hydrogen Embrittlement Relief) |
| Salt Spray Resistance | 48 Hours Neutral Salt Spray (NSS) | 72 – 96 Hours Neutral Salt Spray (NSS) |
| Thread Fitting | Metric 6g / Imperial Class 2A Fit | Metric 6g / Imperial Class 2A Fit |
Electro-Galvanizing and Production Process for Zinc Plated Hex Bolt
At our manufacturing plant in Handan, China, every batch of electro-zinc plated hex bolts undergoes precise cold heading, thread forming, and eco-friendly electroplating:
- Precision Cold Heading & Threading: High-speed multi-station cold formers shape the hexagonal head with crisp bevels and clear property marks (4.8 or 8.8), followed by precision thread rolling.
- Acid Washing & Degreasing: Bolt blanks are thoroughly cleaned to ensure a contaminant-free surface for maximum zinc coating adhesion.
- Electro-Zinc Plating & Cr3+ Passivation: An even zinc layer is deposited galvanically, followed by environmentally friendly trivalent chromium (Cr3+) blue-white or yellow passivation for enhanced oxidation resistance.
- De-Embrittlement Baking (For Grade 8.8): High-tensile bolts undergo thermal baking post-plating to eliminate hydrogen embrittlement risks under tension.
Industrial Applications and Benefits of Zinc Plated Hex Bolt
Due to their smooth surface appearance, cost-efficiency, and corrosion protection, zinc-plated hex head bolts are ideal for indoor and protected outdoor environments:
- Light & Heavy Structural Assembly: Used with DIN 934 zinc-plated hex nuts, flat washers, and spring washers for steel framing, equipment mounts, and solar brackets.
- Machinery & HVAC Ducting: Fastening industrial enclosure panels, ventilation systems, and mechanical conduits.
- Power Distribution & Utilities: Securing cable tray brackets, strut channels, and substation mounting hardware.
Quality Assurance and Export Packaging for Zinc Plated Hex Bolt
Handan YiHao Fastener adheres to rigorous Quality Control (QC) standards for all overseas orders. We perform coating thickness gauge testing, thread ring gauge inspections, neutral salt spray testing, and assembly torque checks.
For maritime export, goods are packed in 25kg reinforced inner cartons, stacked neatly on ISPM 15 compliant fumigated wooden pallets, and securely stretch-wrapped to protect against moisture during transit.
Request Factory Direct Pricing for Zinc Plated Hex Bolts
Looking for a trusted manufacturer in Handan, China for Class 4.8 or Grade 8.8 electro-zinc plated hex bolts? Contact Handan YiHao Fastener today for detailed product specs, full thread/partial thread options, pre-assembled bolt sets (bolt + nut + washer), and direct bulk factory quotes.
