Heli-coil A3591-3CN570 Screw-locking Insert 10-32 Unf

Product Description

The HELI-COIL A3591-3CN570 is a tangless screw-locking helical wire insert designed to create a permanent, vibration-resistant threaded connection in parent material. Manufactured from Grade 304 stainless steel with a bright finish, this insert accepts a 10-32 UNF screw thread and provides a 3D length-to-diameter ratio with an overall length of 0.57 inches. The locking design generates a prevailing torque on the installed fastener, resisting loosening under dynamic loads. It installs without a tang-break step, streamlining the installation process in production and field repair applications. Maintenance technicians, field service engineers, and assembly professionals working on precision equipment use this insert to restore or reinforce thread integrity in metal components.

This insert is suited for applications requiring reliable thread locking in stainless-compatible assemblies, including industrial machinery, aerospace ground support equipment, and mechanical enclosures. The 10-32 UNF thread size is common in instrumentation panels, small motor housings, and precision sheet metal assemblies. The tangless design eliminates the tang removal step required with standard helical inserts, making it particularly useful in blind-hole applications and high-volume assembly lines where foreign object debris is a concern.

Key Features

• Grade 304 stainless steel construction resists corrosion in harsh or outdoor service environments
• Tangless design eliminates tang-break step, reducing installation time and FOD risk in blind holes
• 10-32 UNF thread standard fits a wide range of precision fastener applications
• Maximum locking torque of 13 inch-pounds provides reliable prevailing torque on the mating fastener
• Minimum breakaway torque of 2.00 ounce-inches ensures the insert remains securely seated after installation
• Outside diameter range of 0.236 to 0.256 inches for controlled fit in the prepared parent-material bore
• Bright finish with 14-7/8 free coils for consistent spring action and thread engagement

Compatibility

Designed as an OEM-style thread repair and thread reinforcement insert for assemblies using 10-32 UNF fasteners in metal parent materials requiring a 3D insert length.

Installation Notes

Installation of helical wire inserts requires a properly sized HELI-COIL or compatible tangless insert driver and a correctly dimensioned tap for the parent material bore. Always follow the insert manufacturer's tap drill and tap size chart for the specific thread size and insert length before drilling or tapping. Power down or de-energize any equipment before performing thread repair work on live assemblies. Tangless inserts do not require a tang-removal tool, but the correct tangless installation tool must be used to avoid damaging the coil geometry.