Nylon insert locknuts, also known as nyloc nuts, are a type of locknut that includes a nylon collar insert. The nylon insert is usually located towards the top of the nut’s threads. These nuts are designed to prevent loosening due to vibration or torque.

Here’s how they work:

1. Nylon Insert: The nylon insert inside the nut creates friction against the mating threads of the bolt or stud. This friction helps prevent the nut from coming loose over time, even in applications with constant vibrations.
2. Self-Locking: As the nut is threaded onto a bolt or stud, the nylon insert deforms slightly. This deformation creates a tight grip on the threads, making the nut self-locking.
3. Reusable: While they are effective at preventing unintentional loosening, nylon insert locknuts are generally reusable, although the effectiveness of the nylon insert may decrease with each use.
4. Materials: These nuts are typically made from materials like stainless steel, carbon steel, or other alloys, depending on the specific application and environmental conditions.
5. Applications: Nylon insert locknuts are commonly used in various industries, including automotive, construction, and machinery, where vibration and movement can cause traditional nuts to come loose.

It’s important to note that while these nuts provide a good degree of locking capability, they may not be suitable for all applications. In some cases, alternative locking methods such as lock washers, cotter pins, or thread-locking adhesives might be used depending on the specific requirements of the project.