Heli-coil A4184-4CN080 Screw-locking Insert M4 X 0.70

Product Description

The HELI-COIL A4184-4CN080 is a tangless screw-locking helical wire insert designed to create a strong, vibration-resistant threaded hole in parent materials. Manufactured from Grade 304 stainless steel with a bright finish, it accepts an M4 x 0.70 metric coarse thread and measures 8 mm in overall length, giving it a 2D length-to-diameter ratio. The coiled insert expands against the parent bore wall to lock in place, and the locking coils grip the fastener to resist loosening under dynamic load. Machinists, maintenance technicians, and assembly professionals install this insert to repair damaged threads or to reinforce tapped holes in softer base materials.

This insert is suited for precision thread repair and new-hole reinforcement in applications where corrosion resistance and vibration resistance are required. The tangless design eliminates the need to remove a tang after installation, reducing debris risk in assemblies where loose metal fragments are a concern. Typical install scenarios include aerospace component repair, industrial equipment maintenance, and medical device assembly where Grade 304 stainless steel is specified for its corrosion resistance and non-magnetic properties.

Key Features

• Tangless design eliminates post-installation tang removal, reducing contamination risk in clean assemblies
• Grade 304 stainless steel construction provides corrosion resistance in wet or chemically active environments
• 2D length-to-diameter ratio (8 mm overall length) suits standard thread engagement depth requirements
• Maximum locking torque of 0.90 N/m with a minimum breakaway torque of 0.16 N/m for controlled fastener retention
• Outside diameter range of 5.05 mm to 5.60 mm for secure interference fit in properly prepared parent bores
• Bright finish with 8-5/8 free coils for consistent installation performance

Compatibility

Designed as an OEM-style thread insert for M4 x 0.70 metric coarse threaded holes requiring a 2D insert length in parent materials prepared to HELI-COIL specification drill and tap dimensions.

Installation Notes

Installation requires a properly sized HELI-COIL tap to prepare the parent bore before the insert is driven in with the appropriate tangless installation tool. Power down all equipment and secure workpieces before beginning thread repair operations. Do not attempt to install this insert in an undersized or un-tapped bore, as improper installation can damage the insert and the parent material. Follow the tool manufacturer's torque and installation depth guidance to ensure correct seating.