S-91571A268 5/8"-11 x 2 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 load-bearing capacity with 120,000 psi tensile strength for reliable performance in heavy-duty structural applications
• Superior material durability through ASTM A325 steel construction and Rockwell C19 hardness for extended service life
• Optimized thread engagement with UNC coarse threading and Class 2A fit ensuring secure fastening in demanding environments
• Industry-standard compliance meeting ASME B18.2.6, ASTM A325, and ASTM F3125 specifications for quality assurance
• Enhanced installation efficiency with external hex drive design providing superior torque transmission during assembly
• Environmental responsibility through RoHS 3 and REACH compliance for sustainable industrial operations
• Versatile partial threading allowing precise clamp load control across various material thicknesses

Professional Applications & Engineering Value

These Grade A325 hex head screws deliver critical engineering solutions for structural steel connections, heavy machinery assembly, and construction applications where vibration resistance and structural integrity are paramount. The ASTM A325 steel composition provides exceptional shear strength and fatigue resistance, while the UNC coarse thread pattern ensures rapid installation and reliable performance in structural steel, bridge construction, and industrial equipment. The partially threaded design concentrates clamping force precisely where needed, preventing joint loosening under dynamic loads. With external hex drive compatibility, these fasteners accommodate standard industrial tools for efficient installation in confined spaces, making them ideal for critical connections in building frameworks, transmission towers, and heavy equipment manufacturing where failure is not an option.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance ensuring consistent performance across applications. Complies with ASME B18.2.6 dimensional specifications and ASTM A325/ASTM F3125 material and mechanical requirements. Meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations for hazardous substance restriction. Thread specifications include 5/8"-11 UNC coarse thread with right-hand direction and partial threading configuration.