What is a cap nut

As the name suggests, a cap nut is a hexagonal nut with a cover. The main function of the cover is to prevent the exposed part on the outside from being fastened, in order to prevent moisture or other corrosive substances from entering the inside and thus play a role in rust prevention, thereby improving the service life of itself and the connecting parts.
The size of the cap nut used for different sizes of bolts varies, and higher cap nuts are used for extra long bolts. There is also a self-locking cap nut with twisted threads in the hexagonal area to form a tight friction fit and prevent the nut from loosening due to vibration.

 Application scenarios
The purpose of the cap nut is the same as that of the hexagonal nut. Its characteristic is that the main nut is not easy to slide, but can only be tightened with a flexible wrench, a solid wrench, a dual-purpose wrench (for the opening part), or a special square hole socket wrench. Mainly used for rough and simple components, in tires and front and rear axles of cars, tricycles, electric vehicles, etc., it can also be used to fix road light frame bases and some mechanical equipment that are often exposed to sunlight and rain.