S-91571A322 7/8"-9 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 tensile strength of 120,000 psi ensures reliable performance in the most demanding structural and heavy-duty applications, reducing the risk of fastener failure.
• High hardness rating (Rockwell C19) provides superior resistance to wear and deformation, extending the service life of your assemblies.
li>Coarse UNC threading allows for faster installation and easier alignment, saving valuable time on the job site.
• Partially threaded design provides an unthreaded grip length for superior clamping force in shear-critical connections.
• Precise Class 2A thread fit ensures consistent, reliable engagement with nuts for a secure and vibration-resistant joint.
• Full compliance with major industry standards (ASME, ASTM) guarantees material quality, dimensional accuracy, and performance you can trust.
• Environmentally compliant construction (RoHS 3, REACH) makes this screw suitable for use in regulated markets and sustainable projects.

Professional Applications & Engineering Value

Engineered for heavy-duty construction and critical structural connections, this Grade A325 steel hex head screw solves key engineering challenges. Its high tensile strength and robust Rockwell C19 hardness prevent stripping and failure under extreme loads, making it ideal for steel framing, bridge work, and heavy machinery. The coarse UNC thread and external hex drive facilitate quick installation with standard tools, even in tough field conditions. The partially threaded shank with a defined grip length ensures that the clamping force is applied precisely where needed, providing superior joint integrity in shear connections. This fastener delivers predictable, reliable performance that meets the rigorous demands of professional industrial applications.

Specification Summary & Compliance

This screw features a 7/8"-9 UNC thread with a Class 2A fit for dimensional accuracy and reliable assembly. It is manufactured in compliance with ASME B18.2.6, ASTM A325, and ASTM F3125 specifications, ensuring consistent quality and performance. The product is also verified to be RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental and safety regulations for industrial use.