Value Collection KP78220 Hex Lock Nut 1-1/4-7 Grade 8 5 Pack

Product Description

The VALUE COLLECTION KP78220 is a 1-1/4-7 UNC hex lock nut with a nylon insert locking style, manufactured from Grade 8 steel with a zinc yellow dichromate finish. The nylon insert creates interference with the mating bolt threads to resist loosening caused by vibration and torque. At 1-25/64 inches in height and 1-13/16 inches across the flats, this nut is sized for heavy-duty fastening applications. The zinc yellow dichromate coating provides corrosion resistance in demanding environments. Each package contains 5 nuts. Maintenance technicians, millwrights, and mechanical contractors routinely specify Grade 8 nylon insert lock nuts where joint integrity under dynamic load is required.

This lock nut is suited for industrial, commercial, and heavy equipment assembly applications where a UNC right-hand thread pattern is called for. The 1-1/4-7 thread size positions it for use in structural connections, machinery frames, and large-diameter fastener assemblies. The nylon insert style is a common choice when a prevailing-torque locking method is needed without thread deformation or chemical adhesives.

Key Features

• Nylon insert locking style provides prevailing-torque resistance against vibration-induced loosening
• Grade 8 steel construction for high tensile and proof-load strength
• Zinc yellow dichromate finish for corrosion resistance
• 1-1/4-7 UNC right-hand thread pattern
• 1-25/64 inches height and 1-13/16 inches width across flats for standard hex tooling
• Sold in a pack of 5 per package

Compatibility

Designed for use with 1-1/4-7 UNC right-hand threaded fasteners in Grade 8 or compatible bolt assemblies requiring a prevailing-torque nylon insert lock nut.

Installation Notes

Installation is typically performed by millwrights, maintenance mechanics, or mechanical contractors using standard hex wrenches or impact tooling sized for 1-13/16 inches across the flats. De-energize and lock out all equipment before servicing any fastened assembly. Nylon insert lock nuts are single-use by design — once the insert has been fully engaged and removed, replacement with a new nut is recommended to maintain locking effectiveness. Consult applicable structural or machinery codes for minimum engagement length and torque requirements.