S-91571A426 5/8"-11 x 8" 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 and Grade A325 classification, ensuring reliable performance in high-stress structural applications.
• Superior durability and wear resistance from Rockwell C19 hardness, providing long-term reliability in demanding industrial environments.
• Optimized load distribution through the partially threaded design and 6 3/4" grip length, reducing stress concentration and enhancing joint integrity.
• Easy installation and removal with the external hex drive and 1 1/16" head width, allowing for efficient assembly using standard tools.
• Precise thread engagement with Class 2A thread fit and 5/8"-11 UNC coarse threading, ensuring secure fastening and resistance to vibration loosening.
• Compliance with industry standards including ASME B18.2.6, ASTM A325, and ASTM F3125, guaranteeing consistent quality and interoperability.
• Environmentally responsible manufacturing with RoHS 3 and REACH compliance, meeting global regulatory requirements for hazardous substance restrictions.

Professional Applications & Engineering Value

This Grade A325 heavy-duty hex head screw is engineered to address critical challenges in structural and industrial fastening. The steel construction combined with high tensile strength (120,000 psi) and Rockwell C19 hardness ensures resilience under dynamic loads and harsh conditions, preventing failure in applications like construction frameworks, bridge assemblies, and heavy machinery. The partially threaded design with a 6 3/4" grip length concentrates clamping force on the unthreaded shank, minimizing thread shear and improving fatigue resistance. With 5/8"-11 UNC coarse threads and external hex drive, it enables quick installation in structural bolting scenarios, reducing assembly time while maintaining alignment accuracy. This screw is ideal for projects requiring dependable, high-strength connections that comply with rigorous engineering standards.

Specification Summary & Compliance

This screw features precise Class 2A thread fit and UNC coarse threading per industry norms, ensuring dimensional accuracy and compatibility. It adheres to ASME B18.2.6, ASTM A325, and ASTM F3125 specifications for manufacturing consistency. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), confirming the absence of restricted substances for safe use in global markets.