Value Collection MP31286 Castle Lock Nut 5/8-18 Grade 5 10 Pack

Product Description

The VALUE COLLECTION MP31286 is a 5/8-18 hex castle lock nut manufactured from Grade 5 steel with a zinc-plated finish. Castle lock nuts feature a slotted crown that accepts a cotter pin or safety wire, preventing the nut from loosening under vibration or dynamic loads. The right-hand thread conforms to SAE standard J995. This fastener is used across HVAC equipment, plumbing support assemblies, and general mechanical installations where positive locking retention is required. Each order ships in a package quantity of 10 nuts.

Castle lock nuts in the 5/8-18 thread size are common in shaft-end and bearing-retention applications found in fan assemblies, pump drives, and structural bracketing on commercial and residential mechanical systems. The zinc-plated finish provides a baseline level of corrosion resistance suitable for indoor and light-exposure environments. Licensed tradespeople and maintenance technicians working on equipment with rotating shafts or high-vibration mounting points will find this nut appropriate for those service scenarios.

Key Features

• Castle crown design accepts cotter pin or safety wire for positive anti-rotation locking
• 5/8-18 unified fine thread (UNF) right-hand configuration
• Grade 5 steel construction meets SAE J995 mechanical requirements
• Zinc-plated finish for corrosion resistance in light-duty service environments
• Sold in a 10-piece package quantity

Compatibility

Designed as a standard 5/8-18 UNF right-hand threaded castle lock nut suitable for general mechanical, HVAC, and plumbing support applications where SAE J995-grade fasteners are specified.

Installation Notes

Installation is performed by maintenance technicians and licensed tradespeople using standard open-end, box, or socket wrenches sized for the 5/8-inch hex. Always de-energize and lock out equipment before servicing any fastener on rotating assemblies. After torquing to the equipment manufacturer's specification, align the castle slots with the cotter pin hole and install a new cotter pin or safety wire — never reuse a deformed cotter pin. Confirm thread engagement and seating before returning equipment to service.