S-91251A392 5/16"-24 x 2 1/4" 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 in critical applications.
• Superior corrosion resistance from the black-oxide finish on alloy steel extends service life in harsh industrial environments, minimizing maintenance and replacement costs.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies, enhancing joint integrity in machinery and equipment.
• Fine thread spacing (UNF) offers improved adjustment and clamping force control, ideal for applications requiring fine-tuning and reduced loosening.
• Partially threaded design allows for unthreaded shank sections to bear shear loads effectively, optimizing strength where full threading isn't needed.
• 1/4" hex drive compatibility enables easy installation with standard tools, speeding up assembly processes and reducing labor time.
• High hardness (Rockwell C37) resists wear and deformation, ensuring long-term durability in repetitive or high-load scenarios.

Professional Applications & Engineering Value

This 5/16"-24 UNF Socket Head Cap Screw is engineered to address common industrial challenges, such as vibration-induced loosening and corrosion in demanding environments. Crafted from black-oxide alloy steel, it combines high tensile strength with enhanced rust protection, making it ideal for machinery, automotive, and aerospace assemblies where reliability is critical. The fine thread spacing and Class 3A fit ensure secure fastening in precision equipment, reducing downtime from maintenance. Its partially threaded rod type allows the unthreaded portion to handle shear stresses, providing added stability in structural applications. Compliant with ASTM A574, it meets rigorous standards for high-strength fasteners, offering engineers a dependable solution for heavy-duty and vibration-prone setups.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including Class 3A thread fit for tight tolerances and UNF fine thread spacing (5/16"-24). It is manufactured in accordance with ASTM A574 specifications for high-strength socket head cap screws. Compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), ensuring environmental safety and regulatory adherence for industrial use.