S-91571A338 1"-8 x 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 tensile strength of 120,000 psi ensures reliable performance in heavy-duty applications, reducing the risk of fastener failure under high stress.
• High hardness rating (Rockwell C19) provides superior resistance to wear and deformation, extending the service life of the screw in demanding environments.
• Coarse UNC threading with Class 2A fit allows for quick and easy installation, minimizing assembly time while maintaining secure fastening.
• Partially threaded design offers optimal grip length (2 1/4"), enabling precise clamping force distribution and reducing the chance of joint loosening.
• Compliance with ASME B18.2.6, ASTM A325, and ASTM F3125 standards guarantees consistent quality and interoperability in structural and industrial projects.
• RoHS 3 and REACH compliance ensures environmental safety and regulatory adherence, making it suitable for global supply chains and sensitive applications.
• External hex drive and right-hand thread facilitate straightforward installation with standard tools, enhancing efficiency in construction and assembly lines.

Professional Applications & Engineering Value

This Grade A325 hex head screw is engineered to address critical challenges in heavy-duty industrial and construction applications, such as structural steel connections and machinery assembly. The steel material and coarse UNC thread design provide robust resistance to vibration and dynamic loads, preventing common issues like loosening or shear failure. With a partially threaded configuration, it ensures precise load-bearing capacity by concentrating stress on the unthreaded shank, ideal for high-strength bolting in bridges, buildings, and equipment frames. The external hex drive allows for efficient torque application, reducing installation time while meeting ASME B18.2.6 and other key standards for reliability in demanding environments.

Specification Summary & Compliance

This screw features precise Class 2A thread fit and UNC coarse threading with a 1"-8 size, ensuring dimensional accuracy per industry standards. It complies with ASME B18.2.6, ASTM A325, and ASTM F3125 specifications for manufacturing consistency. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, adhering to environmental and safety regulations for global use.