What is the difference between a Keensert and Heli-Coil?

Keensert and Heli-Coil are both types of threaded inserts used to repair damaged threads or reinforce weak ones in various materials, such as metal or plastic. While they serve a similar purpose, there are some differences between them:

1. Design and Installation:
   • Keensert: Keensert, also known as Key-Locking Inserts, have external threads and feature keys or locking rings on the outside. These keys lock into the host material, providing a high level of torque and pull-out resistance. Keenserts are installed using standard taps and drills for the appropriate size.
   • Heli-Coil: Heli-Coil inserts are wire coils with internal threads. They are installed by tapping a hole larger than the original damaged threads and then threading the Heli-Coil insert into the newly tapped hole using a special tool.
2. Thread Reinforcement:
   • Keensert: Keenserts are known for their excellent resistance to vibration and dynamic loads due to the locking keys. They provide a more secure and reliable thread reinforcement in high-stress applications.
   • Heli-Coil: Heli-Coils provide good thread reinforcement but may not offer the same level of resistance to vibration and dynamic loads as Keenserts. They are generally more suitable for lighter-duty applications.
3. Material Compatibility:
   • Keensert: Keenserts are available in various materials, including stainless steel, carbon steel, and brass, making them suitable for a wide range of applications.
   • Heli-Coil: Heli-Coils are typically made of stainless steel and are also available in various materials, but they may not offer as extensive a selection as Keenserts.
4. Thread Types:
   • Keensert: Keenserts are available with both standard (inch) and metric threads, making them versatile for different applications.
   • Heli-Coil: Heli-Coils are also available in both standard and metric threads, offering flexibility in thread size options.
5. Cost:
   • Keensert: Keenserts are generally considered more expensive than Heli-Coils due to their design and locking feature.

In summary, both Keensert and Heli-Coil inserts are used for thread repair and reinforcement, but the choice between them depends on the specific application’s requirements. Keenserts are known for their higher torque and pull-out resistance, making them suitable for heavy-duty applications with strong vibration or dynamic loads. Heli-Coils are more cost-effective and suitable for lighter-duty applications. Ultimately, the choice should be based on the specific needs of your project and the expected stresses the threaded insert will encounter.