Lock nuts include non-metallic nested nuts, embedded st […]
Lock nuts include non-metallic nested nuts, embedded steel sheet nuts, embedded spring steel wire nuts, flange indentation nuts, flattened nuts, etc. Non-metallic nested nut GB889 (namely nylon lock nut): This kind of nut has no anti-loose property, only some anti-off property. It clamps the bolt by the tension of the nylon ring. Embedded steel sheet nut GB6187 (metal lock nut): The essence is that the embedded steel sheet is perpendicular to the nut axis and parallel to the end surface of the nut. The tooth profile angle and pitch of the last thread are changed by the embedded steel sheet. The steel sheet is used Its own elasticity is used to prevent loosening, and the effect of preventing loosening is weak.
Spring wire nut (that is, wire thread insert): There are two parts inside the nut. The pitch of the spring is different from the pitch of the thread. The inner diameter of the spring is small and it has a little anti-dropping property. Flat nut (three-head flat nut): In good conditions, it is equivalent to the combination of ordinary nut and lock nut, with certain anti-loosening performance, but the consistency is very poor, and it is not suitable for multiple use.
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 middle round nut. There are 3, 4, 6 or 8 gaps on the circumference of the nut (depending on the size of the nut and the product series of the manufacturer). Several notches are not only the focus of the tightening tool, but also the insertion place of the locking washer.
The third type is to drill through threaded holes from the outer surface of the nut to the inner thread surface (usually two, distributed at 90 on the outer surface), used to screw in small diameter countersunk screws, the purpose is to thread Apply a centripetal force to prevent the lock nut from loosening. At present, the lock nuts of better quality on the market are inlaid on the inner surface of the nut with copper small pieces that are consistent with the thread of the lock nut, which is used to prevent the radial jacking screw from directly contacting the locked thread and causing damage. By. This kind of lock nut has gradually begun to be applied in the occasion of the shaft end locking of rotating parts, such as the anti-loosening of the bearing at the mounting end of the ball screw.
The second anti-loose method is more reliable than the first, but the structure is relatively complicated. Compared with the first two, the third clock has the characteristics of better anti-loose effect, simpler and more beautiful structure and smaller axial size.