S-91375A591 5/16"-18 x 2" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Enhanced corrosion resistance with black-oxide coating for reliable performance in demanding industrial environments
• Superior holding power from Class 3A thread fit ensuring precise, vibration-resistant fastening in critical applications
• High-strength durability with Rockwell C45 hardness providing exceptional load-bearing capacity and wear resistance
• Secure installation through hex drive design allowing high torque application without head protrusion in confined spaces
• Optimized grip performance with cup tip design creating concentrated pressure points for superior component retention
• Reliable coarse threading with UNC 5/16"-18 specification enabling quick assembly and reduced cross-threading risks
• Extended service life through alloy steel construction maintaining integrity under repeated stress and temperature variations

Professional Applications & Engineering Value

This black-oxide alloy steel set screw delivers exceptional engineering value in industrial applications where vibration resistance and permanent positioning are critical. The headless design with hex drive provides flush mounting capabilities while allowing high torque installation in confined machinery spaces. The UNC coarse thread pattern combined with Class 3A fit ensures rapid assembly with minimal cross-threading risk, making it ideal for production environments. The cup tip configuration creates concentrated pressure points that prevent component slippage in high-vibration equipment, while the Rockwell C45 hardness maintains structural integrity under heavy cyclic loading. These features make it particularly valuable for securing gears, pulleys, and collars in manufacturing equipment, automotive assemblies, and heavy machinery where reliable fastening is non-negotiable.

Specification Summary & Compliance

This set screw maintains precision thread dimensions with UNC 5/16"-18 coarse threading and Class 3A fit tolerance for exacting industrial requirements. Manufacturing conforms to ASME B18.3 specifications and ASTM F912 material standards, ensuring consistent quality and performance. The product is fully RoHS 3 (2015/863/EU) compliant and meets REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial applications without hazardous substance restrictions.