The difference between self-locking screw and lock nut

In some important occasions, we will take some anti-loose measures to ensure the reliability of the locking of the hardware nut. The use of lock nuts is one of the anti-loosening measures. The working principle of the nut is self-locking by the friction between the nut and the bolt. However, the reliability of this self-locking under dynamic load will be reduced.

There are three types of lock nuts:

The first is to use two same nuts to screw on the same bolt, and add a tightening torque between the two nuts to make the bolt connection reliable. (Guide: Reasons for the slippage of the self-drilling screw)

The second type is a special lock nut, which needs to be used together with a lock washer. The special lock nut is not a hexagonal nut, but a round nut. The ball screw has 3 to 8 gaps on the circumference of the nut (depending on the size of the nut and the product series of the manufacturer). These gaps are both The focus point of the tightening tool is the snap-in place of the anti-loosening washer bayonet.

The third type is to drill through threaded holes from the outer surface of the nut to the inner thread surface (usually 2~3, uniformly distributed on the outer surface), which is used to screw in small diameter countersunk screws , The purpose is to apply a centripetal force to the thread to prevent the lock nut from loosening. The disadvantage of this kind of lock nut is that it is difficult to disassemble and re-assemble and disassemble.

More relevant stamping die development industry news: