Heli-coil 1185-5CN469S Free Running Insert 5/16-18 500 Pack

Product Description

The HELI-COIL 1185-5CN469S is a free running helical wire thread insert designed to create strong, wear-resistant internal threads in parent materials that are too soft, damaged, or otherwise unsuitable for direct tapping. Manufactured from 304 stainless steel, this tanged insert measures 0.469 inches overall length and accepts a 5/16-18 UNC thread. The coil design distributes load evenly across multiple thread convolutions, significantly increasing pull-out strength and extending service life in high-cycle or high-vibration applications. Licensed HVAC technicians, plumbers, machinists, and maintenance professionals routinely use these inserts to restore stripped threads or build in stainless-grade thread strength during original fabrication.

This insert is suited for residential and commercial maintenance, OEM assembly, and field repair work wherever a 5/16-18 UNC threaded hole requires reinforcement or restoration. The 1-1/2D length-to-diameter ratio makes it a standard choice for general-purpose fastening applications across equipment housings, compressor brackets, access panels, pump bodies, and other threaded connections requiring a durable, corrosion-resistant insert. Each package contains 500 inserts, supporting high-volume production or stocking requirements for service fleets and shop inventories.

Key Features

• 304 stainless steel construction provides corrosion resistance in wet or chemically exposed environments
• 5/16-18 UNC thread size with 0.469 inches overall length suits a wide range of general-purpose fastening applications
• Tanged design allows installation and tang break-off using standard HELI-COIL installation tooling
• 6-5/8 free coils and 1-1/2D length-to-diameter ratio deliver balanced load distribution and pull-out resistance
• 500-insert pack quantity supports production runs, fleet service trucks, and shop stock programs

Compatibility

Designed for use in any parent material tapped to accept a 5/16-18 UNC free running helical insert; requires the appropriate HELI-COIL STI tap and installation tool for this thread size and insert length.

Installation Notes

Installation is typically performed by a machinist, maintenance technician, or qualified trade professional using an STI tap to prepare the parent hole, followed by a dedicated installation tool to drive the insert to the correct depth. Power down or de-energize any equipment before performing thread repair on live assemblies. Break off the tang after installation using a tang break-off tool or long-nose pliers; never leave the tang in a blind hole. Follow the insert manufacturer tooling charts for correct tap drill size and tap engagement depth to avoid oversizing the parent bore.