Locknut is a kind of nut widely used in machinery and other industries (like centrifugal pump manufacturing). Its working principle is self-locking by the friction between nut and bolt. However, the reliability of this self-locking in dynamic loads is reduced. In some important cases, we will take some anti-loose measures to ensure the reliability of the nut locking.
Types
The first is to use two identical nuts to screw on the same bolt, and a tightening torque is added between the two nuts to make the bolt connection reliable.
The second type is a special locknut that needs to be used with a lockable gasket. The special locknut is not a hex nut, but a round nut with 3, 4, 6 or 8 notches on the circumference of the nut (depending on the size of the nut and the manufacturer's product range), this Several notches are the point of focus of the tightening tool and the snap-in of the lock tab.
The third type is a threaded hole (usually two, 90 in the outer circular surface) drilled through the outer surface of the nut to the inner circular thread surface, for screwing a small diameter countersunk head screw for the purpose of threading Apply a force in the centripetal direction to prevent the lock nut from loosening. A better quality lock nut sold on the market is provided with a small piece of copper on the inner circumference of the nut that is aligned with the thread of the lock nut to prevent the radial cap screw from directly contacting the locked thread and damaging the latter. . This kind of lock nut is gradually applied in the case of the shaft end locking of the rotary motion type parts, such as the anti-looseness of the ball screw mounting end bearing.
The fourth type of lock nut is composed of two parts, each part has a staggered cam. Since the internal wedge type design has a slope angle larger than the nut angle of the bolt, the combination is tightly bitten into a whole, when vibration occurs. When the protruding portions of the locknut are displaced from each other, a lifting tension is generated, thereby achieving a perfect anti-loosening effect.
The fifth type is structure anti-loose. By design improvement on the thread structure, a self-owned locking function is obtained without using other external factors, so the applicability is wider than the above several methods, and the environmental requirements are also compared. low. There are many types of locknuts, such as nylon nuts, and flange nuts. In short, the locknuts are anti-loosening. Twist the nut to the screw, screw, bolt, etc., so that it will not fall off. Enable them to be actively coupled together to make them strong and stable to a high degree
