S-91831A143 9/16"-18 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance with nylon insert locking technology that maintains secure fastening under dynamic loads
• Excellent corrosion protection from 18-8 stainless steel construction for long-term reliability in harsh environments
• High-temperature performance with nylon insert rated to 220°F (104°C) for demanding industrial applications
• Precise thread engagement with Class 2B UNF fine threads ensuring consistent clamping force and reduced loosening
• Easy installation and removal using standard wrench tools with the external hex drive design
• Regulatory compliance meeting RoHS 3 and REACH standards for safe use in regulated industries
• Dimensional accuracy with 7/8" width and 41/64" height for reliable fit in assembly applications

Professional Applications & Engineering Value

This 9/16"-18 UNF nylon insert locknut delivers critical vibration resistance in demanding industrial applications where secure fastening is paramount. The 18-8 stainless steel construction provides exceptional corrosion resistance, making it ideal for machinery, automotive, and marine environments where moisture and chemicals are present. The nylon insert locking mechanism creates consistent friction against mating threads, preventing loosening from vibration and thermal cycling while allowing for multiple reuses. With a 220°F temperature rating, this external hex locknut maintains performance in elevated temperature conditions common in engine compartments, industrial equipment, and processing systems. The UNF fine threads offer superior thread engagement compared to coarse threads, distributing stress more evenly and providing enhanced sealing capabilities in pressurized applications.

Specification Summary & Compliance

This locknut features Class 2B thread fit per UNF standards, ensuring precise dimensional accuracy and reliable performance. The manufacturing complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances. The right-hand 9/16"-18 UNF fine thread specification provides optimal thread engagement for high-strength applications, while the standard hex profile (7/8" across flats, 41/64" height) ensures compatibility with conventional wrenching tools and industrial assembly processes.