S-91247A734 1/2"-13 x 5 1/2" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 120,000 psi tensile strength, ideal for demanding structural and machinery applications.
• Superior corrosion resistance provided by zinc plating, extending service life in various industrial environments.
• Reliable fastening performance ensured by Grade 5 strength classification and Rockwell C25 hardness for consistent durability.
• Efficient installation and removal with external hex drive and 3/4" head width, allowing for high torque application with standard tools.
• Optimized thread engagement through coarse UNC threading and Class 2A fit, reducing cross-threading risks in assembly.
• Versatile partial threading design with 1-1/4" minimum thread length, providing strong clamping force on thick materials.
• Full regulatory compliance meeting ASME B18.2.1, SAE J429, RoHS 3, and REACH standards for quality assurance and environmental safety.

Professional Applications & Engineering Value

This Grade 5 hex head screw delivers critical engineering value through its zinc plated steel construction, providing essential corrosion protection in industrial environments where moisture and chemicals are present. The 1/2"-13 UNC coarse thread configuration ensures rapid installation and superior resistance to vibration loosening, making it ideal for heavy machinery, structural steel connections, and equipment manufacturing. The partially threaded design concentrates clamping force precisely where needed, preventing joint failure in high-stress applications. With external hex drive compatibility, maintenance crews can achieve proper preload using standard wrenches, reducing assembly time and ensuring consistent torque values across multiple fastening points in complex industrial assemblies.

Specification Summary & Compliance

This industrial fastener maintains Class 2A thread fit tolerances per UNC standards, ensuring consistent threading compatibility. Manufacturing conforms to ASME B18.2.1 and SAE J429 specifications for dimensional accuracy and mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, containing no restricted substances. With precise 5-1/2" length and 1-1/4" minimum thread length, this fastener delivers reliable performance across industrial applications requiring Grade 5 mechanical properties.