Definition
Nylon insert lock nuts—also known as nylon nuts and stop nuts—are a prevailing torque, locking nut that resists loosening caused by vibration and normal use. Unlike free spinning hex nuts, lock nuts make use of a deforming elastic or metal material to stay in position against torque and shock.
Application
The nylon insert locknut comes with an insert that fits the threads of the screw it is placed on and causes a gripping action due to the friction it creates. This, in turn, lessens the chance that the nut will become loose because of vibrations.
Although the name nylon insert locknut creates the impression that they actually lock, they do not. Depending on the amount of vibration in the application that the locknut is used for, the parts may become loose, but they will not come apart because of the friction that results between the locknut and the threads.
