S-92991A218 5/16"-18 x 5/16" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from high-quality brass construction for extended service life in demanding environments
• Precise Class 3A thread fit ensures reliable, vibration-resistant fastening with minimal backlash in assemblies
• Optimal hardness (Rockwell B55) provides excellent wear resistance while maintaining necessary ductility
• Secure hex drive (5/32") delivers maximum torque transmission without stripping during installation
• Effective cup tip design creates positive seating and prevents component slippage in permanent applications
• Right-hand coarse UNC threads enable rapid installation and removal while maintaining holding strength
• Comprehensive regulatory compliance meets ASME B18.3, RoHS 3, and REACH standards for global industrial use

Professional Applications & Engineering Value

This 5/16"-18 UNC brass set screw delivers exceptional performance in precision positioning and permanent fastening applications where corrosion resistance is critical. The Class 3A thread fit provides superior engagement with mating components, eliminating play in assemblies subject to vibration or thermal cycling. Engineered with Rockwell B55 hardness, this fastener maintains dimensional stability under load while the cup tip design creates concentrated contact pressure to prevent shaft or component rotation. The hex drive configuration ensures reliable installation in confined spaces, making these headless set screws ideal for machinery, electrical enclosures, and marine equipment where exposed fastener heads are impractical. The combination of brass material and coarse thread spacing provides excellent performance in environments requiring both chemical resistance and rapid assembly.

Specification Summary & Compliance

This precision set screw features 5/16"-18 UNC coarse threads with Class 3A thread fit for exacting dimensional accuracy. The fastener meets ASME B18.3 manufacturing specifications and demonstrates full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. With a thread diameter of 0.313" and length of 5/16", this inch-system component is manufactured to industrial standards for reliable performance in technical applications requiring precise thread engagement and regulatory adherence.