Value Collection CNFI5037-100BX Castle Lock Nut 3/8-24

Product Description

The VALUE COLLECTION CNFI5037-100BX is a castle lock nut designed for threaded fastener applications requiring positive locking. Machined from Grade 5 steel with a bright uncoated finish, this nut features a 3/8-24 thread size with right-hand thread direction. The castellated crown accepts a cotter pin or safety wire to prevent rotation under vibration or dynamic loads. At 13/32 inches high with a 9/16-inch width across flats, it fits standard 9/16-inch wrenches. It meets ANSI B18.2.2 dimensional standards. Installers in mechanical, HVAC, plumbing, and general industrial applications rely on this fastener type where thread locking without thread deformation is required.

This castle lock nut is suited for use in residential and light commercial mechanical assemblies where vibration resistance is necessary without permanent fastener deformation. It is commonly installed on threaded rod, shafts, and bolted joints in HVAC equipment frames, piping supports, and general mechanical assemblies. The 3/8-24 fine thread pitch provides greater tensile strength and finer adjustment compared to coarse thread equivalents, making it appropriate for load-bearing and precision-fit applications.

Key Features

• Castle (castellated) design accepts cotter pin or safety wire for positive locking
• Grade 5 steel construction for reliable tensile and proof load performance
• 3/8-24 fine thread, right-hand direction per ANSI B18.2.2
• Bright uncoated finish suitable for applications not requiring corrosion protection
• 9/16-inch width across flats fits standard combination and box-end wrenches

Compatibility

Designed as a standard ANSI B18.2.2 castle lock nut for use with 3/8-24 fine-thread fastener systems in mechanical, HVAC, and industrial equipment assemblies.

Installation Notes

Installation is performed by licensed mechanics and trades professionals using a standard 9/16-inch wrench. Before servicing any assembly, de-energize electrical systems and depressurize fluid systems per applicable codes. After torquing to the assembly specification, align the castle slots with the cotter pin hole in the bolt or shaft before inserting the cotter pin or safety wire. Do not substitute a standard hex nut where a castle nut and cotter pin are specified by the equipment manufacturer.