Circular step nuts are often paired with stopper washers. During assembly, insert the tongue of the washer into the slot of the shaft, and the outer tongue of the washer into the slot of the circular step nut, thereby securing the nut. They are commonly used for axially fixing rolling bearings.

The differences between round step nuts and small round step nuts:

1. In terms of usage

Circular step nuts are primarily used for end locking of shafts, often used together with lock washers, typically featuring fine threads. The concept of nuts is quite broad, generally including hex nuts, wing nuts, self-locking nuts, etc., which are commonly used for bolt connections. Small circular step nuts are used to fix the axial displacement of driving and rotating parts, and are often paired with lock washers to secure the inner rings of rolling bearings. Removal and installation of nuts require the use of a hook spanner.

2. In terms of size

Specification Standard – GB Standard

Small round step nut, GB 810-88

Circular step nuts GB 812-88