S-91251A017 1 1/4"-12 x 3 1/2" 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 applications, reducing the risk of fastener failure.
• Black-oxide coating on alloy steel provides corrosion resistance and a durable, non-reflective finish suitable for harsh industrial environments.
• Fine UNRF thread with Class 2A fit offers precise engagement and vibration resistance, maintaining secure connections in dynamic machinery.
• 7/8" hex drive and standard socket head allow for easy installation and high torque application with common tools, minimizing assembly time.
• Fully threaded design ensures consistent clamping force along the entire 3 1/2" length, ideal for thick materials and adjustable placements.
• Rockwell C37 hardness enhances wear resistance and longevity, supporting repeated use without degradation in demanding settings.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety, meeting global industrial standards.

Professional Applications & Engineering Value

This Black-Oxide Alloy Steel Socket Head Cap Screw is engineered to address common industrial challenges such as vibration loosening and corrosion in heavy machinery. The fine UNRF thread and Class 2A fit provide superior thread engagement, reducing the need for frequent retightening in equipment like presses, conveyors, and automotive assemblies. Its high tensile strength and Rockwell C37 hardness ensure it withstands extreme loads and abrasive conditions, while the black-oxide surface treatment adds a protective layer against moisture and chemicals. Ideal for precision engineering applications, this screw offers reliable performance in construction, manufacturing, and aerospace sectors where durability and compliance with ASTM A574 standards are critical.

Specification Summary & Compliance

This socket head cap screw features a 1 1/4"-12 UNRF fine thread with Class 2A dimensional tolerance for precise fit, and it is fully threaded with a length of 3 1/2". Manufactured in accordance with ASTM A574 specifications, it ensures consistent quality and performance. The product is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and suitable for international industrial use.