S-91247A510 7/8"-14 x 5 1/2" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 120,000 psi tensile strength and Grade 5 classification for reliable performance in demanding applications
• Enhanced corrosion resistance through zinc plating that protects against rust and extends service life in harsh industrial environments
• Precise thread engagement with 7/8"-14 UNF fine threading and Class 2A fit ensuring secure fastening and vibration resistance
• Optimized torque transmission thanks to the external hex drive and 1 5/16" head width for easy installation with standard tools
• Controlled thread distribution through partial threading design that provides both gripping power and clearance where needed
• Consistent mechanical properties with Rockwell C25 hardness ensuring durability and resistance to deformation under stress
• Regulatory compliance assurance meeting ASME B18.2.1, SAE J429 standards while being RoHS 3 and REACH compliant for global applications

Professional Applications & Engineering Value

This Grade 5 hex head screw delivers exceptional engineering value through its zinc plated steel construction and 7/8"-14 UNF fine threading. The combination of 120,000 psi tensile strength and Rockwell C25 hardness addresses critical industrial challenges by preventing thread stripping and maintaining clamp load under vibration. The partially threaded design allows for precise load distribution in heavy machinery, structural steel connections, and equipment assembly where both shear strength and tension integrity are paramount. The external hex drive with substantial head dimensions ensures reliable torque application without slippage, while the Class 2A thread fit guarantees consistent performance across multiple installations. These industrial fasteners are engineered to withstand cyclical loading and environmental exposure in construction, manufacturing, and heavy equipment applications.

Specification Summary & Compliance

This hex head screw features precise Class 2A thread fit with 7/8"-14 UNF fine threading and minimum 2" thread length. Manufacturing conforms to ASME B18.2.1 specifications where identified as SAE J429 for dimensional accuracy and mechanical properties. The fastener demonstrates full compliance with RoHS 3 (2015/863/EU) restrictions on hazardous substances and REACH (EC 1907/2006) regulations regarding chemical substances of very high concern, ensuring environmental responsibility and global market acceptance.