S-91253A483 5/16"-18 x 5" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 psi ensures reliable performance in demanding applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide coating on alloy steel extends service life in harsh industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies in critical machinery.
• Hex drive design allows for high-torque installation with standard tools, speeding up assembly and maintenance processes.
• Partially threaded shank offers optimal grip and clamping force, preventing material damage in wood and metal applications.
• 82° countersink angle ensures a flush, professional finish that minimizes protrusion and improves safety.
• Compliance with ASME B18.3 and ASTM F835 guarantees consistent quality and interchangeability for engineering projects.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these 5/16"-18 UNC flat head screws solve critical fastening challenges in machinery, construction, and equipment assembly. The black-oxide alloy steel construction provides excellent resistance to wear and environmental factors, while the coarse UNC thread and Class 3A fit ensure quick, secure installation in coarse-grained materials like cast iron or structural steel. The hex drive and partially threaded design allow for efficient torque application and reduced stress concentration, making them ideal for applications requiring repeated disassembly and reassembly without compromising joint integrity.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit for precision and meets ASME B18.3 and ASTM F835 manufacturing standards. It is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, ensuring environmental safety and regulatory adherence for global supply chains.