S-91770A594 5/16"-18 x 2 1/2" ASME B18.6.3 Stainless Steel Truss Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction for long-lasting performance in harsh environments
• Enhanced load distribution thanks to the wide truss head design that reduces surface pressure and prevents material damage
• High mechanical strength with 70,000 psi tensile strength and Rockwell B70 hardness for reliable heavy-duty applications
• Quick and secure installation through No. 4 Phillips drive and UNC coarse threading that prevents cross-threading
• Optimized thread engagement with Class 2A thread fit ensuring consistent fastening performance and vibration resistance
• Versatile partial threading allowing for both secure clamping and adjustment flexibility in various assembly scenarios
• Regulatory compliance assurance meeting industry standards for quality and environmental safety requirements

Professional Applications & Engineering Value

These passivated 18-8 stainless steel truss head screws deliver exceptional engineering value in demanding industrial environments where corrosion resistance and structural integrity are paramount. The wide truss head design provides significantly larger bearing surface compared to standard heads, effectively distributing clamping forces across wider areas to prevent surface damage to assembled materials. This feature is particularly valuable in applications involving softer materials or thin sheet metals where traditional fasteners might cause deformation. The combination of UNC coarse threading and partial threading enables rapid assembly while maintaining precise control over clamping pressure, making these Phillips drive screws ideal for production lines requiring both speed and reliability. The 70,000 psi tensile strength ensures these fasteners maintain integrity under substantial mechanical stress, while the corrosion-resistant properties make them suitable for outdoor equipment, marine applications, chemical processing facilities, and food processing machinery where exposure to moisture and corrosive elements is common.

Specification Summary & Compliance

This 5/16"-18 x 2 1/2" truss head screw features precision Class 2A thread fit according to UNC standards, ensuring consistent engagement and reliable performance. Manufacturing and dimensional specifications strictly comply with ASME B18.6.3 standards for industrial quality assurance. The product is fully compliant with RoHS 3 (2015/863/EU) restrictions on hazardous substances and meets REACH (EC 1907/2006) requirements for chemical safety, including the latest SVHC updates as of June 14, 2023. The inch system measurements maintain dimensional accuracy with a head diameter of 0.698", head height of 0.183", and minimum thread length of 1 1/2" for consistent performance across industrial applications.