S-91385A578 5/16"-18 x 1/2" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Superior vibration resistance with integrated nylon patch thread locker that maintains secure fastening from -50°F to 250°F
• Exceptional durability through black-oxide alloy steel construction with Rockwell C45 hardness for long service life
• Precise thread engagement with Class 3A thread fit ensuring reliable performance in demanding applications
• Easy installation and removal with standard 5/32" hex drive design requiring minimal clearance
• Optimized clamping force through cup tip design that provides concentrated contact pressure
• Industry-standard compatibility with UNC coarse thread spacing (5/16"-18) for broad application use
• Regulatory compliance assurance meeting ASME B18.3 specifications and environmental standards (RoHS 3 & REACH)

Professional Applications & Engineering Value

This 5/16"-18 UNC set screw delivers critical engineering solutions for industrial applications requiring permanent, vibration-resistant fastening. The black-oxide alloy steel construction provides excellent corrosion resistance while maintaining Rockwell C45 hardness for superior strength in high-stress environments. The integrated nylon patch thread locker eliminates the need for separate locking compounds, maintaining secure fastening across extreme temperature ranges from -50°F to 250°F. The headless design with hex drive allows for installation in confined spaces while the cup tip ensures maximum holding power by concentrating pressure on a small contact area. Ideal for precision machinery, automotive components, and industrial equipment where vibration resistance and reliable performance are paramount.

Specification Summary & Compliance

This set screw features Class 3A thread fit for precision tolerance in unified coarse thread applications (5/16"-18 UNC). Manufactured to ASME B18.3 specifications with compliance to ASTM F912 standards. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental regulations for industrial use. The right-hand thread direction with coarse spacing provides optimal engagement in various materials while maintaining dimensional accuracy throughout the fastener's service life.