The Full Hex Nut (commonly known as a hexagonal nut, metric hex nut, or DIN 934 / ISO 4032 fastener) is the fundamental internally threaded component specified across global construction, structural steel framing, automotive manufacturing, power transmission line towers, and machinery assembly. Designed to mate perfectly with hex bolts, stud bolts, and threaded rods, our hex nuts are engineered in carbon steel (Property Classes 4, 8, and 10) and austenitic stainless steel (Grades SS304/A2-70 and SS316/A4-80) in strict compliance with global ISO standards.
Comprehensive Technical Specifications of Hex Nuts
We produce a complete spectrum of strength grades and surface protections to match specific bolt property classes and environmental conditions. Over-tapped threads are specifically offered for hot-dip galvanized nuts to accommodate thick zinc layers without thread binding.
| Property Class / Grade | Raw Material Base | Proof Stress Rating | Mating Bolt Recommendation | Available Surface Treatments |
|---|---|---|---|---|
| Class 4 / Class 6 | Low Carbon Steel (Q195 / Q235B) | 400 – 600 N/mm² | Class 4.6, 4.8, 5.8 Bolts & Rods | Plain, Electro-Zinc Plated (Blue-White / Yellow) |
| Class 8 (High Tensile) | Medium Carbon Steel (45#) | 800 N/mm² | Class 8.8 High Tensile Bolts & Studs | Black Oxide, Electro-Zinc, Hot-Dip Galvanized (HDG) |
| Class 10 (Extra High Tensile) | Quenched & Tempered Alloy (40Cr) | 1000 N/mm² | Class 10.9 Structural Bolts | Black Oxide, Electro-Zinc, Dacromet, HDG |
| Stainless A2-70 / A2-80 | Austenitic Stainless Steel SS304 (1.4301) | 700 – 800 N/mm² | A2-70 / A2-80 Stainless Bolts & Screws | Passivated Clean Natural / Electropolished |
| Stainless A4-70 / A4-80 | Austenitic Stainless Steel SS316 (1.4401) | 700 – 800 N/mm² | A4-70 / A4-80 Marine Grade Fasteners | Passivated Clean Natural / Electropolished |
Precision Cold Heading, Tapping and Surface Treatment Process
At our manufacturing plant in Handan, China, hex nuts undergo automated multi-station cold forming, precision internal tapping, heat treatment, and surface plating:
- Multi-Station Cold Heading: High-speed automated former machinery punches raw wire rods into uniform hexagonal geometry and pierces central core holes with minimal material waste.
- High-Precision Internal Tapping: Automatic tapping units cut 6H standard metric threads (or over-tapped 6AZ threads for HDG nuts) to guarantee smooth hand-tightening without thread galling.
- Continuous Thermal Heat Treatment (Classes 8 & 10): Carbon steel nuts pass through controlled atmosphere mesh-belt quenching and tempering furnaces to achieve uniform hardness and 800–1000 MPa proof strength.
- Advanced Surface Coating Options: Electro-zinc plating (5–15 µm), Hot-Dip Galvanizing (45–85 µm molten zinc immersion), and stainless steel chemical passivation.
Versatile Industrial Applications of Hex Nuts
Hex nuts serve as the essential clamping fastener across all structural and mechanical engineering domains:
- Power Transmission Towers & Substation Hardware: Class 8 HDG hex nuts secured on double-end studs and cross-arm bolts in outdoor electrical grids.
- Structural Steel Construction & Bridges: Class 8 and Class 10 heavy hex nuts assembled with high-tensile structural bolts on steel beams.
- Sanitary, Food & Marine Equipment: SS304 / SS316 stainless steel nuts deployed in chemical plants, dairy equipment, and coastal marine installations.
Quality Control and Export Packaging for Hex Nuts
Handan YiHao Fastener enforces comprehensive Quality Assurance (QA) standards for all overseas export shipments. Testing procedures include 100% thread plug gauge go/no-go checks, proof load testing, Rockwell/Vickers hardness testing, coating thickness gauge measurement, and salt spray testing.
All export orders are bulk packed in heavy-duty 25kg inner cartons, neatly stacked on ISPM 15 compliant fumigated wooden pallets, and shrink-wrapped for safe maritime transportation.
Request Factory Direct Pricing for Carbon Steel & Stainless Steel Hex Nuts
Looking for a trusted manufacturer in Handan, China for carbon steel or stainless steel hex nuts (Class 4, Class 8, Class 10, A2-70, A4-80, DIN 934 / ISO 4032)? Contact Handan YiHao Fastener today for technical datasheets, over-tapped HDG options, sample shipments, and direct bulk export quotes.
