S-90185A417 5/16"-18 x 7/8" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Superior anti-rotation performance thanks to the integrated square neck that locks securely into materials, preventing spinning during installation and use.
• Exceptional tensile strength and durability with a Grade 5 rating and 120,000 psi tensile strength, ensuring reliable performance under high-stress conditions.
• Enhanced corrosion resistance from the zinc-plated steel construction, providing long-lasting protection in demanding industrial environments.
• Precise and reliable fastening with Class 3A thread fit and UNC coarse threading, offering excellent engagement and vibration resistance.
• Wide head profile for superior load distribution, reducing the risk of material damage and providing a secure, flush finish.
• Full threading for versatile application, allowing for deep penetration and secure fastening across a wide range of material thicknesses.
• Compliance with major industry standards including ASME B18.5 and SAE J429, ensuring quality and interoperability in professional settings.

Professional Applications & Engineering Value

This Grade 5 carriage bolt is engineered to solve critical fastening challenges in industrial applications where vibration resistance and structural integrity are paramount. The zinc-plated steel construction combats corrosion, extending service life in harsh environments, while the square neck design effectively prevents rotation during torque application, a common issue in wood-to-metal and structural assemblies. The UNC coarse thread and Class 3A thread fit ensure quick assembly and a secure, precise fit, reducing the risk of strip-out in soft materials or under dynamic loads. Its 120,000 psi tensile strength and Rockwell C25 hardness make it an ideal choice for heavy-duty frameworks, machinery, and construction projects requiring dependable, long-lasting connections.

Specification Summary & Compliance

This carriage bolt features a 5/16"-18 UNC thread with a Class 3A thread fit, ensuring high precision and reliability. It is manufactured from zinc-plated steel and conforms to ASME B18.5 and SAE J429 standards for dimensional accuracy and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its safety and environmental responsibility for global industrial use.