S-91251A605 1 1/4"-12 x 8" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance in high-stress industrial applications, reducing the risk of fastener failure.
• Durable Black-Oxide finish on alloy steel provides corrosion resistance and a sleek appearance, extending service life in various environments.
• Precision UNRF fine threading with Class 2A fit offers superior vibration resistance and secure fastening in critical assemblies.
• Partially threaded design allows for precise clamping force control, minimizing damage to materials and improving joint integrity.
• Rockwell C37 hardness delivers excellent wear resistance, maintaining thread integrity through repeated use and high-torque applications.
• 7/8" hex socket drive enables easy installation with standard tools, reducing assembly time and improving workflow efficiency.
• Compliance with ASTM A574, RoHS 3, and REACH ensures material quality and environmental safety, meeting global regulatory standards for industrial use.

Professional Applications & Engineering Value

This Black-Oxide Alloy Steel Socket Head Cap Screw is engineered to address common challenges in heavy-duty machinery, automotive, and construction sectors. Its UNRF fine thread and Class 2A fit provide enhanced resistance to loosening under vibration, a critical need in dynamic load environments. The partially threaded rod type allows for precise unthreaded shank sections, reducing stress concentration and preventing thread galling in high-clamp force applications. With a tensile strength of 170,000 psi and Rockwell C37 hardness, it withstands extreme mechanical stresses, making it ideal for bolted connections in structural frames, industrial equipment, and precision assemblies where reliability and durability are paramount.

Specification Summary & Compliance

This screw features a 1 1/4"-12 UNRF fine thread with Class 2A thread fit for precise dimensional accuracy, ensuring consistent performance in inch-system applications. It is manufactured in compliance with ASTM A574 specifications for high-strength alloy steel socket head cap screws, and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, confirming its suitability for global industrial use without hazardous substances.