S-91274A492 1/2"-13 x 4" ASME B18.3, ASTM A574, ASTM B117 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-flake coating, ideal for harsh industrial environments and extending service life.
• Exceptional tensile strength of 170,000 PSI ensures reliable performance under high-stress conditions, reducing the risk of fastener failure.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies in critical applications.
• High hardness (Rockwell C37) enhances wear resistance and durability, maintaining integrity through repeated use.
• 3/8" hex drive design allows for easy installation and high torque application with standard tools, improving assembly efficiency.
• Partially threaded shank offers optimal grip and alignment in fastened joints, minimizing loosening in dynamic loads.
• Compliance with major standards including ASME B18.3 and ASTM A574 guarantees consistent quality and interoperability in professional settings.

Professional Applications & Engineering Value

This 1/2"-13 UNC Socket Head Cap Screw is engineered to address common industrial challenges such as corrosion, vibration loosening, and high-load demands. The zinc-flake-coated alloy steel construction provides robust protection against rust and chemical exposure, making it suitable for outdoor machinery, automotive assemblies, and heavy equipment. With a coarse thread and Class 3A fit, it ensures quick, secure fastening in materials like steel and cast iron, reducing installation time and maintenance needs. Its partially threaded design concentrates clamping force effectively, preventing joint failure in applications like construction frameworks and industrial automation systems. By integrating high tensile strength and standardized dimensions, this screw delivers reliable performance in demanding environments, enhancing overall project safety and longevity.

Specification Summary & Compliance

This product features precise UNC coarse threads with a Class 3A thread fit for accurate engagement and consistent performance. It adheres to ASME B18.3 and ASTM A574 manufacturing standards, ensuring dimensional reliability and mechanical properties. Additionally, it complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmental safety and regulatory requirements in global industrial supply chains.