S-91274A484 1/2"-13 x 3 1/2" ASME B18.3, ASTM A574, ASTM B117 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under extreme loads, reducing the risk of fastener failure in critical applications.
• Superior corrosion resistance provided by the zinc-flake coating extends service life in harsh industrial environments, minimizing maintenance and replacement costs.
• Precision Class 3A thread fit guarantees secure, vibration-resistant assemblies with consistent clamping force and reduced loosening over time.
• High hardness (Rockwell C37) offers excellent wear resistance and durability, maintaining thread integrity through repeated installations.
• Partially threaded design allows for precise grip length control, ideal for applications requiring specific unthreaded shank sections.
• 3/8" hex drive compatibility enables easy installation with standard tools, improving assembly efficiency and reducing labor time.
• Compliance with ASME B18.3 and ASTM A574 ensures consistent quality, dimensional accuracy, and interoperability with other standardized components.

Professional Applications & Engineering Value

This 1/2"-13 UNC Socket Head Cap Screw is engineered to address common industrial challenges such as joint integrity under dynamic loads and exposure to corrosive elements. The zinc-flake-coated alloy steel construction provides a robust barrier against rust and chemical degradation, making it suitable for machinery, automotive assemblies, and structural frameworks where environmental resistance is critical. The coarse UNC thread and Class 3A fit ensure quick, reliable fastening in high-vibration settings, while the partially threaded rod design offers flexibility in applications requiring precise load-bearing sections. By integrating high tensile strength with standardized dimensions, this fastener reduces assembly errors and enhances the longevity of heavy-duty equipment, delivering consistent performance in demanding engineering environments.

Specification Summary & Compliance

This socket head cap screw adheres to ASME B18.3 and ASTM A574 specifications, ensuring precise dimensional control and mechanical properties. The UNC coarse thread is manufactured to Class 3A tolerance for superior fit and reliability. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming the absence of hazardous substances. Additionally, the coating meets ASTM B117 standards for corrosion resistance, supporting use in regulated industrial and construction applications.