S-90185A169 5/16"-18 x 1" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Superior anti-rotation performance thanks to the integrated square neck design that prevents spinning during installation and under vibration
• Exceptional tensile strength and durability with a Grade 5 rating and 120,000 psi tensile strength for reliable use in heavy-duty applications
• Enhanced corrosion resistance provided by the zinc-flake coating, extending the bolt's service life in demanding industrial environments
• Optimized for quick installation with coarse UNC threading and a fully threaded design for faster assembly and secure fastening
• Wide, rounded head profile distributes clamping force effectively and provides a finished appearance while reducing surface damage
• Consistent quality and reliability ensured by Rockwell C25 hardness and compliance with major industrial standards
• Secure fit and interchangeability guaranteed by Class 2A thread fit, ensuring compatibility with standard nuts and components

Professional Applications & Engineering Value

This Grade 5 carriage bolt is engineered to solve critical fastening challenges in structural and heavy machinery applications. The zinc-flake coated steel construction provides robust protection against corrosion, which is essential for outdoor equipment, agricultural machinery, and construction frameworks exposed to harsh elements. The square neck is a key engineering feature that locks securely into the mating material, preventing rotation during torque application and under dynamic loads—this eliminates the need for secondary locking mechanisms and reduces assembly time. The coarse UNC thread ensures rapid installation and high resistance to vibration loosening, making it ideal for wood-to-metal connections, trailer assemblies, and structural steel work where reliability is non-negotiable. With its 120,000 psi tensile strength, this bolt maintains integrity under significant stress, providing engineers with a trusted solution for demanding industrial applications.

Specification Summary & Compliance

This carriage bolt features a 5/16"-18 UNC coarse thread with a Class 2A thread fit for standard tolerance and reliable engagement. It is manufactured in compliance with ASME B18.5 and SAE J429 specifications, ensuring dimensional accuracy and mechanical performance. The product is certified RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting stringent environmental and safety regulations for industrial use.