| Item | Specification Details |
|---|---|
| Product Name | Carriage Bolt / Round Head Square Neck Bolt |
| Material | Q235 High Strength Carbon Steel |
| Surface Finish | Blue White Zinc Plated, Anti-rust Treatment |
| Standard Sizes | M6, M8, M10, M12, M14, M16; Custom thread length available |
| Structure | Oversized smooth domed round head + integrated square anti-rotation neck + full rolling thread shank |
| Applicable Materials | Wood planks, steel sheet, metal brackets, guardrails, garden furniture, agricultural equipment, playground facilities |
| Core Features | Smooth burr-free round head for safe contact; square neck locks workpiece to stop bolt spinning during tightening; large head surface to disperse pressure and prevent sinking in wood; standard uniform thread for matching nuts; cost-effective anti-corrosion plating |
| Application Scenarios | Outdoor fence assembly, wooden outdoor furniture connection, farm machinery installation, timber & metal composite structures, public leisure equipment fixing |
| Custom Service | OEM & ODM, customized thread length, adjustable head diameter, special surface coating (yellow zinc, black zinc) |
Carriage Bolt
Carriage Bolt, also known as round head square neck bolt, is a special anti-rotation fastener designed for combined assembly of wood and metal materials.
This bolt is integrally forged from carbon steel. Its wide smooth round head has no sharp edges, which can avoid scratching workers and matching parts, and evenly spread clamping pressure to prevent the bolt head from sinking into soft wood panels. The square neck under the head is the core anti-slip structure: after inserting into pre-punched square holes of plates, the square neck will be embedded into the workpiece to fix the bolt body firmly, so the bolt will not rotate when twisting nuts without auxiliary clamping tools.
The full precision rolling thread can perfectly cooperate with standard hex nuts and flat washers to provide stable long-term clamping force. Blue white zinc plating forms a dense rust-proof protective film on the steel surface, effectively resisting oxidation and mild outdoor humid environment, suitable for conventional workshop and outdoor general projects.
All finished carriage bolts pass tensile strength and thread accuracy inspection before shipment, meeting construction and furniture fastening safety standards. Custom thread lengths and head sizes can be produced to adapt to different plate thickness and load demands for bulk export orders.
