Understanding the Carriage Bolt: A Comprehensive Guide

When it comes to reliable and secure fastening solutions, the carriage bolt stands out for its unique design and versatility. Also known as a coach bolt, this fastener is easily recognizable by its square neck section beneath the domed or rounded head. This square neck is the key feature that prevents the bolt from rotating during tightening, making it ideal for applications where a smooth, finished appearance is desired on one side of the assembly. The Square Neck Bolt is engineered for use in wood, metal, and other materials, providing a strong, non-loosening hold. Its common applications range from furniture and construction to agricultural equipment and trailers. The Square Neck Bolt design ensures that the fastener remains securely in place, even under significant vibration or load, making it a trusted choice for both professionals and DIY enthusiasts seeking a permanent and aesthetically pleasing fastening solution. The Square Neck Bolt is a specific type of carriage bolt that emphasizes this anti-rotation feature, crucial for structural integrity.

The primary advantage of the Carriage Bolt is its simplicity and effectiveness. The domed head offers a smooth, low-profile finish that reduces the risk of snagging and injury, which is particularly important in furniture and public structures. The square neck pulls into the material as the nut is tightened, locking the bolt firmly in place and eliminating the need for a wrench on the head side. This makes installation faster and more straightforward, especially in hard-to-reach areas. The Carriage Bolt is designed to provide a clean, finished look, which is why it is often the preferred choice for visible applications. Furthermore, the Carriage Bolt is available in a variety of materials, sizes, and finishes to suit different environmental conditions and load requirements, ensuring long-term durability and performance.

Detailed Product Specifications

Materials and Finishes

• Materials: Available in Stainless Steel, Carbon Steel, Zinc-Plated Steel, and Hot-Dip Galvanized Steel.
• Finishes: Plain, Zinc Plated, Hot-Dip Galvanized, and Dichromate.

Standard Sizes and Dimensions (ASTM Standards)

Mechanical Properties

• Grade 2: Minimum tensile strength of 60,000 psi.
• Grade 5: Minimum tensile strength of 120,000 psi.
• Grade 8: Minimum tensile strength of 150,000 psi.
• Stainless Steel 18-8: Good corrosion resistance and a tensile strength of approximately 70,000 psi.

Industry Standards and Compliance

• ASTM A307 - Standard Specification for Carbon Steel Bolts and Studs.
• ASTM F593 - Standard Specification for Stainless Steel Bolts, Hex Cap Screws, and Studs.
• SAE J429 - Standard for Mechanical and Material Requirements for Externally Threaded Fasteners.