What is the primary purpose of a nylon insert in a lock nut?

What is the primary purpose of a nylon insert in a lock nut?

• A. To increase friction and prevent loosening
• B. To reduce weight
• C. To improve electrical conductivity
• D. To resist corrosion

Answer: (A)

Locking nylon insert nuts are designed to resist vibration-caused loosening by increasing friction between the nut’s threads and the bolt’s threads. The nylon insert sits inside the nut and deforms as the bolt is threaded in. That deformation creates a higher friction bite and a slight elastic bite that makes the nut harder to turn once it’s tightened, so it stays secure even when subjected to vibration or dynamic loads. This friction-based locking action is the essential purpose. The other ideas aren’t the main goal: the insert doesn’t primarily reduce weight, improve electrical conductivity (nylon is an insulator, not a conductor), or provide corrosion resistance as the key function. The nylon’s main role is to create a locking action through friction.

Locking nylon insert nuts are designed to resist vibration-caused loosening by increasing friction between the nut’s threads and the bolt’s threads. The nylon insert sits inside the nut and deforms as the bolt is threaded in. That deformation creates a higher friction bite and a slight elastic bite that makes the nut harder to turn once it’s tightened, so it stays secure even when subjected to vibration or dynamic loads. This friction-based locking action is the essential purpose.

The other ideas aren’t the main goal: the insert doesn’t primarily reduce weight, improve electrical conductivity (nylon is an insulator, not a conductor), or provide corrosion resistance as the key function. The nylon’s main role is to create a locking action through friction.