S-91251A948 1 1/4"-7 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 under high-stress conditions, reducing the risk of fastener failure.
• Durable black-oxide coating on alloy steel provides enhanced corrosion resistance, extending service life in demanding industrial environments.
• Coarse UNRC thread design offers faster installation and superior grip in a wide range of materials, improving assembly efficiency.
• Partially threaded shank allows for precise clamping force control, minimizing the risk of thread damage and ensuring secure fastening.
• Hex socket drive with 7/8" drive size enables high-torque application and easy access in confined spaces, streamlining maintenance and installation.
• Rockwell C37 hardness provides excellent wear resistance, maintaining thread integrity and performance over repeated use.
• Compliance with ASTM A574, RoHS 3, and REACH ensures material quality and environmental safety, meeting rigorous industry and regulatory standards.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address critical challenges in heavy-duty industrial applications, such as machinery assembly, construction equipment, and automotive systems. The 1 1/4"-7 coarse UNRC thread and partially threaded design facilitate quick, secure fastening in high-vibration environments, preventing loosening and reducing maintenance downtime. The high tensile strength and Rockwell C37 hardness ensure durability under extreme loads, while the black-oxide surface treatment enhances corrosion resistance, making it ideal for outdoor or harsh conditions. By integrating precise Class 2A thread fit and a standardized hex drive, this fastener delivers consistent performance, improving operational efficiency and reliability in engineering projects that demand robust, long-lasting solutions.

Specification Summary & Compliance

This socket head cap screw features a 1 1/4"-7 coarse UNRC thread with Class 2A thread fit for precise dimensional accuracy. It is manufactured in accordance with ASTM A574 specifications, ensuring consistent quality and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its adherence to environmental and safety standards for industrial use.