S-91571A416 5/8"-11 x 3 1/4" ASME B18.2.6, ASTM A325, ASTM F3125 Medium-Strength Steel Heavy Hex Head Screws for Structural Applications

Key Features & Benefits at a Glance

• Exceptional structural integrity with 120,000 PSI tensile strength and Rockwell C19 hardness for reliable performance in demanding applications
• Superior clamping force achieved through 2" grip length and partially threaded design for secure connections in structural assemblies
• Precise thread engagement with Class 2A thread fit and 5/8"-11 UNC coarse threads ensuring easy installation and vibration resistance
• Heavy-duty material construction using Grade A325 steel for maximum durability and load-bearing capacity
• Industry-standard compliance meeting ASME B18.2.6, ASTM A325, and ASTM F3125 specifications for guaranteed quality and reliability
• Environmental responsibility with RoHS 3 and REACH compliance, ensuring safe use in regulated applications
• Optimized installation efficiency featuring external hex drive and 1 1/16" head width for straightforward torque application

Professional Applications & Engineering Value

This Grade A325 heavy-duty hex head screw delivers critical engineering value in structural applications where failure is not an option. The partially threaded design with 2" grip length concentrates clamping force precisely where needed, preventing joint relaxation in structural steel connections, bridge construction, and heavy machinery assemblies. The 5/8"-11 UNC coarse thread configuration resists vibration-induced loosening while enabling faster installation in field applications. Manufactured from high-strength steel with Rockwell C19 hardness, this bolt maintains integrity under extreme loads, solving common challenges of structural deflection and connection fatigue. The external hex drive and substantial head dimensions provide reliable torque transmission, making it ideal for both construction and industrial maintenance applications requiring predictable, repeatable performance.

Specification Summary & Compliance

This structural fastener features Class 2A thread fit tolerance for optimal assembly clearance while maintaining strength requirements. The 5/8"-11 UNC coarse thread follows standardized dimensions with partial threading extending 1 1/4" from the tip. Manufacturing and quality control adhere to ASME B18.2.6, ASTM A325, and ASTM F3125 specifications, ensuring consistent mechanical properties and dimensional accuracy. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) requirements, confirming the absence of restricted substances for use in regulated markets and applications.