S-91247A593 5/16"-18 x 2 1/2" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior load-bearing capacity with 120,000 psi tensile strength for reliable performance in demanding applications
• Enhanced corrosion resistance through zinc plating, extending service life in various industrial environments
• Optimized thread engagement with Class 2A thread fit ensuring consistent assembly and vibration resistance
• High-strength Grade 5 steel construction with Rockwell C25 hardness providing excellent durability and wear resistance
• Quick installation capability with external hex drive design allowing for efficient torque application
• Versatile partial threading enabling precise clamping force control in diverse assembly scenarios
• Industry-standard compliance meeting ASME B18.2.1 and SAE J429 specifications for guaranteed interoperability

Professional Applications & Engineering Value

This 5/16"-18 UNC Grade 5 steel hex head screw delivers exceptional engineering value through its carefully engineered specifications. The coarse thread design combined with partial threading provides superior resistance to vibration loosening in heavy machinery, construction equipment, and automotive assemblies. The zinc plating surface treatment offers reliable corrosion protection in industrial environments where moisture and chemicals are present. With its external hex drive and standardized UNC thread form, this fastener enables rapid installation and removal while maintaining precise Class 2A thread fit tolerances. The Grade 5 steel composition ensures consistent performance in applications requiring repeated disassembly and reassembly, making it ideal for maintenance-heavy industrial settings where fastener reliability directly impacts operational efficiency and safety.

Specification Summary & Compliance

This hex head screw features precise Class 2A thread fit tolerances with 5/16"-18 UNC coarse threading and 2 1/2" length. Manufactured to ASME B18.2.1 and SAE J429 Grade 5 specifications, ensuring dimensional accuracy and mechanical properties. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial applications requiring strict material composition controls.