Value Collection 31285 Castle Lock Nut 9/16-18 Grade 5 Zinc-plated

Product Description

The VALUE COLLECTION 31285 is a 9/16-18 castle lock nut manufactured from Grade 5 steel with a zinc-plated finish. Castle lock nuts feature notched crowns that accept a cotter pin or safety wire, providing positive locking against rotation under vibration and dynamic loads. This fastener uses a right-hand thread and conforms to SAE standard J995. It is used across mechanical, plumbing, HVAC equipment assembly, and general industrial applications wherever a secure, verifiable lock is required. Licensed trades and maintenance technicians rely on this type of nut when standard prevailing-torque hardware is insufficient for the application.

This castle lock nut is suited for residential and commercial equipment assembly, structural fastening, and maintenance applications requiring a mechanically locked connection. The 9/16-18 fine thread pitch provides greater thread engagement per inch compared to coarse thread, making it appropriate for high-load or precision-fit assemblies. Sold in a package of 25 units, this SKU supports both single-job use and shop stocking.

Key Features

• Castle crown design accepts cotter pin or safety wire for positive mechanical locking
• 9/16-18 fine right-hand thread for high thread engagement and load resistance
• Grade 5 steel construction meets SAE J995 fastener standard
• Zinc-plated finish provides basic corrosion resistance in moderate environments
• Packaged in quantities of 25 for efficient job-site or shop use

Compatibility

Designed for use with any 9/16-18 right-hand threaded bolt or stud in applications requiring a castle-style lock nut per SAE J995.

Installation Notes

Installation is performed by hand tools; a standard open-end or socket wrench sized for 9/16-18 hex nuts is required. Always thread the nut by hand first to confirm proper thread engagement before applying torque. After torquing to the fastener assembly specification, align the castle slots with the cotter pin hole in the mating bolt before inserting the cotter pin. Never reuse a cotter pin once it has been bent.