S-91571A298 3/4"-10 x 3" 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 load-bearing capacity with 120,000 psi tensile strength for reliable performance in demanding structural applications
• Superior hardness and durability with Rockwell C19 rating to resist deformation under extreme pressure
• Optimized thread engagement with UNC coarse threads and Class 2A fit for faster installation and secure fastening
• Enhanced torque transmission through 1 1/4" external hex head design for easier installation with standard tools
• Versatile partial threading with 1 3/8" threaded section and 1 5/8" grip length for precise clamping force distribution
• Full regulatory compliance meeting RoHS 3 and REACH environmental standards for safe industrial use
• Proven reliability through compliance with ASME B18.2.6, ASTM A325, and ASTM F3125 specifications

Professional Applications & Engineering Value

These Grade A325 steel hex head screws deliver critical performance in heavy-duty construction and industrial applications where structural integrity is paramount. The combination of 120,000 psi tensile strength and Rockwell C19 hardness ensures these fasteners maintain clamping force under extreme loads, preventing joint failure in structural steel connections, bridge construction, and heavy machinery assembly. The UNC coarse thread design with Class 2A fit provides superior resistance to vibration loosening while enabling quicker installation compared to fine-thread alternatives. The partially threaded configuration with substantial 1 5/8" grip length ensures optimal stress distribution across connected materials, making these 3/4"-10 hex head screws ideal for critical structural connections requiring predictable failure modes and consistent performance.

Specification Summary & Compliance

Manufactured to exacting standards with Class 2A thread fit tolerance for consistent engagement and reliable performance. These 3/4"-10 UNC coarse thread fasteners comply with ASME B18.2.6 dimensional specifications and meet material requirements per ASTM A325 and ASTM F3125 standards. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring safe use across global industrial markets. The external hex drive with 1 1/4" head width and 15/32" head height provides standardized tool interface for consistent installation torque application.