S-91251A140 3/4"-10 x 8 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 industrial applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish on alloy steel extends service life in harsh environments, minimizing maintenance needs.
• Precise Class 3A thread fit provides secure, vibration-resistant connections, enhancing assembly integrity and reducing loosening over time.
• Heavy-duty 5/8" hex drive allows for high-torque installation with standard tools, speeding up assembly and disassembly processes.
• Coarse UNRC threads enable quick engagement and reduced cross-threading risks, ideal for rapid production settings.
• Rockwell C37 hardness offers excellent wear resistance, maintaining thread integrity through repeated use and handling.
• Compliance with ASTM A574, RoHS 3, and REACH ensures 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 critical challenges in heavy machinery, automotive, and construction sectors where high tensile strength and corrosion resistance are paramount. The partially threaded design with coarse 3/4"-10 threads and Class 3A fit ensures rapid, secure fastening in dynamic loads, reducing assembly time and preventing thread stripping. Its alloy steel construction and black-oxide surface treatment provide durability against moisture and chemicals, making it ideal for outdoor or corrosive environments. By integrating a 5/8" hex drive, it supports efficient torque application, minimizing tool slippage and enhancing worker safety in industrial maintenance and manufacturing applications.

Specification Summary & Compliance

This socket head cap screw adheres to Class 3A thread fit for precise dimensional accuracy under UNRC coarse thread standards, with a minimum thread length of 2 inches. It meets ASTM A574 specifications for high-strength alloy steel fasteners, ensuring consistent performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and suitable for global industrial use.