Difference Between a Key Insert and a Helicoil

We have published a few articles pertaining to helicoils, how to install them and how to remove them. However, key inserts provide an alternative to helicoils and they have their own set of inherent benefits and flaws. Key inserts became popular because of the ability to quickly repair stripped or damaged threads without having to discard the original part. There are some very important distinctions between key inserts and helicoils such as their material, finish, and inherent benefits and flaws.

Material

You can find Key inserts made of the following material types:

• 303 Stainless
• 304 Stainless
• 316 Stainless
• 17-4 PH Stainless
• A286 Stainless
• Nitronic 60 Stainless
• 4140 Alloy
• Inconel 718
• Carbon Steel

Finishes:

• Zinc Phosphate
• Passivate
• Cadmium
• Dry-Film Lube
• Silver
• Nickel

Benefits of Key Inserts:

Key inserts are ideal for when a high degree of pull-out strength is required or for when a screw will be moving in and out repeatedly. Unlike helicoils, key inserts do not require a special installation tool and there is no tang to remove.

Flaws of Key Inserts:

Key inserts are a great alternative to helicoils, but they do have their own set of issues. The most common flaw is the size required to install a key inserts. Unlike helicoils which have a slim profile, inserts are extremely large and require a large external thread for installation. The second most common flaw is the removal process. Removal requires drilling out material, bending the key insert and utilizing a screw extractor to remove the insert. This can be a cumbersome process and may prove to be more challenging than removing a helicoil.

Overall, we believe that inserts are more beneficial and pratical than helicoils, but it largely depends on your application. We hope this article has helped you better understand the differences between key inserts and helicoils, and if you have any questions please leave a comment down below.