S-91257A786 9/16"-18 x 5" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 psi tensile strength for reliable performance in high-stress applications
• Superior corrosion resistance through zinc yellow-chromate plating, extending service life in harsh industrial environments
• Precision thread engagement with Class 2A UNF fine threads ensuring secure fastening and vibration resistance
• Enhanced torque transmission through external hex drive design for easier installation and removal
• Optimized weight distribution with partial threading design providing improved clamping force control
• Maximum durability with Rockwell C33 hardness maintaining structural integrity under repeated stress
• Regulatory compliance assurance meeting ASME, SAE, RoHS 3, and REACH standards for quality and safety

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these Grade 8 hex head screws deliver exceptional performance where reliability is critical. The 9/16"-18 UNF fine thread configuration provides superior resistance to vibration loosening, making them ideal for machinery, structural assemblies, and equipment subjected to dynamic loads. The zinc yellow-chromate plating offers enhanced corrosion protection, significantly extending service life in demanding environments while maintaining consistent thread fit Class 2A precision. The partial threading design ensures optimal stress distribution, preventing material deformation in critical joints. These industrial hex screws solve common engineering challenges by combining high tensile strength with corrosion resistance, reducing maintenance frequency and ensuring long-term structural integrity in construction, manufacturing, and heavy equipment applications.

Specification Summary & Compliance

This 5" hex head screw features precise Class 2A thread fit with 9/16"-18 UNF fine threads manufactured to exacting standards. The fastener complies with ASME B18.2.1 and SAE J429 Grade 8 specifications, ensuring dimensional accuracy and mechanical properties. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the product meets current environmental safety standards for industrial use worldwide.