S-91251A805 5/8"-11 x 2 3/4" 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.
• Superior corrosion resistance from the black-oxide finish extends service life in harsh industrial environments, minimizing maintenance needs.
• Precise Class 3A thread fit provides secure, vibration-resistant connections, enhancing assembly integrity and reducing loosening over time.
• High hardness rating (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use and disassembly.
• Partially threaded design allows for optimal clamping force control, ideal for applications requiring specific grip lengths.
• 1/2" hex drive compatibility enables easy installation with standard tools, speeding up assembly processes and reducing labor time.
• Compliance with ASTM A574, RoHS, and REACH ensures material quality and environmental safety, meeting rigorous industrial and regulatory standards.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these black-oxide alloy steel socket head cap screws address critical challenges in machinery, automotive, and construction sectors. The coarse thread (5/8"-11) and Class 3A thread fit provide superior resistance to vibration and dynamic loads, preventing joint failure in high-stress environments. The black-oxide surface treatment enhances corrosion resistance, making these screws ideal for outdoor or humid conditions where durability is paramount. With a partially threaded rod type, they offer precise clamping in assemblies requiring controlled unthreaded shank sections, reducing stress concentration. These features, combined with ASTM A574 compliance, deliver reliable performance in demanding applications like heavy equipment manufacturing, structural frameworks, and precision engineering projects.

Specification Summary & Compliance

This socket head cap screw features a 5/8"-11 coarse thread with Class 3A thread fit per UNRC standards, ensuring high precision and interchangeability. Dimensions include a 2-3/4" length with a minimum thread length of 1-3/4", head diameter of 15/16", and 1/2" hex drive for standard tooling. Manufactured to ASTM A574 specifications, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, confirming adherence to environmental and safety regulations for industrial use.