S-90086A643 5/16"-18 x 3/4" ASME B18.6.3, SAE J933 Tapping Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding industrial environments
• Excellent material compatibility with Type F thread cutting design that creates strong, secure threads in aluminum, brass, cast iron, and sheet metal
• Optimized installation efficiency featuring a standard 82° countersink angle and No. 4 Phillips drive for flush mounting and reliable torque transfer
• Enhanced holding power through fully threaded design with coarse UNC spacing for maximum engagement and vibration resistance
• Industry-standard compliance meeting ASME B18.6.3 specifications for consistent quality and dimensional accuracy
• Environmental responsibility with RoHS 3 compliance, ensuring safe use in regulated applications
• Precision installation guidance with recommended 0.29" drill bit size for proper hole preparation and optimal thread formation

Professional Applications & Engineering Value

These 5/16"-18 UNC tapping screws deliver exceptional engineering value in metal fabrication and assembly operations. The Type F thread cutting design eliminates the need for pre-tapped holes, significantly reducing installation time and labor costs while providing reliable fastening in challenging materials. The zinc-plated steel construction offers superior corrosion protection, making these flat head screws ideal for applications where environmental exposure is a concern. The 82° countersink angle ensures flush mounting in prepared holes, while the coarse thread spacing provides excellent pull-out resistance in softer metals like aluminum and brass. These industrial screws are particularly valuable in sheet metal assemblies, electrical enclosures, and machinery where thread cutting fasteners must maintain integrity under vibration and load stress.

Specification Summary & Compliance

These heavy-duty tapping screws feature precision 5/16"-18 UNC coarse threads with standard Class 2A tolerances for consistent performance. Manufactured to meet ASME B18.6.3 specifications SAE J933, ensuring dimensional accuracy and mechanical properties. The fasteners are fully compliant with RoHS 3 (2015/863/EU) regulations for environmental safety. The flat head profile with standard dimensions (0.597" head diameter, 0.191" head height) and right-hand thread direction provides industry-standard installation compatibility across various applications.