S-91251A563 1/4"-20 x 6 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.
• Precision Class 3A thread fit provides superior engagement and vibration resistance, maintaining secure connections in demanding environments.
• Black-oxide coating on alloy steel offers enhanced corrosion resistance, extending service life in various industrial conditions.
• High Rockwell C37 hardness delivers excellent wear resistance, ensuring durability and reduced maintenance needs.
• Partially threaded design allows for optimal clamping force control, ideal for assemblies requiring precise unthreaded shank sections.
• 3/16" hex drive socket head enables easy installation with standard tools, improving assembly efficiency and reducing labor time.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety, meeting rigorous industry standards.

Professional Applications & Engineering Value

These Black-Oxide Alloy Steel Socket Head Cap Screws are engineered to address critical challenges in industrial and mechanical assemblies. The 1/4"-20 UNC coarse thread and Class 3A fit ensure rapid installation and high resistance to loosening under vibration, making them ideal for machinery, automotive, and heavy equipment. The alloy steel construction with a black-oxide finish combats corrosion and wear, prolonging fastener life in harsh environments. With a 6 1/2" length and partially threaded rod, they provide precise clamping in applications where unthreaded sections prevent thread damage. This combination of high tensile strength and precision engineering supports reliable performance in high-stress applications, reducing downtime and maintenance costs.

Specification Summary & Compliance

This socket head cap screw features a 1/4"-20 UNC coarse thread with Class 3A thread fit for precise tolerances, ensuring consistent performance. It meets ASTM A574 specifications for material quality and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming environmental safety and industry adherence.