S-90185A420 5/16"-18 x 2 3/4" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capacity – Grade 5 classification and 120,000 psi tensile strength ensure reliable performance in demanding applications
• Superior Anti-Rotation Security – Integrated square neck design prevents spinning during installation and maintains permanent positioning
• Enhanced Corrosion Resistance – Zinc-plated steel construction provides durable protection against rust and environmental elements
• Precision Thread Engagement – Class 3A thread fit with UNC coarse threading delivers secure, vibration-resistant connections
• Optimized Material Hardness – Rockwell C25 hardness rating balances strength with machinability for long service life
• Universal Compatibility – Fully threaded design and right-hand threading accommodate various material thicknesses and standard nuts
• Regulatory Compliance Assurance – Meets ASME B18.5 specifications while being RoHS 3 and REACH compliant for global applications

Professional Applications & Engineering Value

This heavy-duty carriage bolt delivers critical engineering solutions where vibration resistance and permanent fastening are paramount. The zinc-plated steel construction combined with Grade 5 strength rating addresses common industrial challenges including structural fatigue, environmental degradation, and load cycling. The square neck design fundamentally solves rotation issues during torque application, making it ideal for wood-to-metal connections, structural framing, and machinery assembly where disassembly isn't anticipated. The UNC coarse threading ensures rapid installation in various materials while maintaining Class 3A thread fit precision for consistent clamping force. These features make it particularly valuable in construction, agricultural equipment, and transportation infrastructure where reliability cannot be compromised.

Specification Summary & Compliance

Manufactured to exacting standards with Class 3A thread fit tolerance and UNC 5/16"-18 coarse thread specifications. The bolt maintains dimensional compliance with ASME B18.5 standards and carries full certification for RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The Grade 5 classification guarantees consistent mechanical properties including the specified 120,000 psi tensile strength and Rockwell C25 hardness throughout production batches.