S-90273A432 5/16"-18 x 5/8" ASME B18.6.3 Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding environments
• Exceptional holding power with 60,000 psi tensile strength and Rockwell B70 hardness for reliable fastening performance
• Optimized flush installation with standard 82° countersink angle and flat head design for smooth surface finishing
• Enhanced driving efficiency with Phillips No. 4 drive for secure tool engagement and reduced cam-out risk
• Reliable thread engagement with Class 2A thread fit and coarse UNC threading for quick assembly and vibration resistance
• Full-threaded design providing maximum grip length and uniform stress distribution across the entire fastener
• Industry compliance assurance meeting ASME B18.6.3 specifications for dimensional accuracy and performance standards

Professional Applications & Engineering Value

These 5/16"-18 UNC flat head screws deliver critical engineering solutions where flush surface mounting and high-strength fastening are paramount. The zinc-plated steel construction provides essential corrosion protection for industrial equipment, machinery assemblies, and outdoor applications exposed to environmental elements. The fully threaded right-hand design with coarse thread spacing ensures rapid installation and superior resistance to vibrational loosening in dynamic operating conditions. The standard 82° countersink angle facilitates perfect flush mounting in predrilled holes, eliminating protrusions that could interfere with moving components or compromise safety. These Phillips drive screws are engineered to maintain integrity under substantial loads, making them ideal for structural assemblies, manufacturing fixtures, and heavy-duty equipment where 60,000 psi tensile strength is required for long-term reliability.

Specification Summary & Compliance

These industrial-grade flat head screws feature precise Class 2A thread fit tolerances with 5/16"-18 UNC coarse threading and right-hand orientation. Manufacturing complies with ASME B18.6.3 dimensional and mechanical specifications, ensuring interchangeability and performance consistency. The products are fully compliant with RoHS 3 (2015/863/EU) restrictions on hazardous substances and REACH (EC 1907/2006) regulations for chemical safety, meeting the latest environmental standards for industrial components.