What Are The Locking Methods Of The Locknut?

The locknut is a common part in mechanical fasteners, which belongs to a kind of fastening locknut. However, in order to avoid the nut slipping during use, it needs to be tightened by some anti loosening methods. Now let's let Xiao Rui take you to know about some locking methods of the locknut.

What are the locking methods of the lock nut? Generally, the following five locking methods are common.

1. Friction locking. This method is the most widely used nut locking method, which generates a positive pressure between screw pairs that does not change with external force to generate a friction force that can prevent the relative rotation of screw pairs. This positive pressure can be achieved by pressing the thread pair axially or in two directions at the same time. For example, elastic washers, double nuts, self-locking nuts and nylon insert lock nuts are used. This nut locking method is convenient for the disassembly of nuts. However, in the case of impact, vibration and variable load, the bolt will be loosened at the beginning, resulting in a decrease in preload. With the increase of vibration times, the loss of preload will slowly increase, which will eventually lead to nut loosening and failure of threaded connection.

2. Mechanical nut locking. This method is based on the principle of using the stopper to directly limit the relative rotation of the thread pair. For example, split pin, tandem wire and stop washer are used. This method makes disassembly inconvenient.

3. Riveting and punching to prevent looseness. After tightening the locknut, punching, welding, bonding and other methods are used to make the thread pair lose the characteristics of the motion pair and become an inseparable connection. The disadvantage of this method of locknut installation is that the bolt rod can only be used once, and it is very difficult to disassemble. The locknut bolt pair must be destroyed before disassembly.

4. Anti loose structure. This method is based on the thread pair's own structure, that is, the principle of Down's thread locking.

5. Punching method is used to prevent looseness. After the nut is tightened, the thread is damaged by punching at the end of the thread; Anaerobic adhesive is usually applied to the screw joint surface to prevent looseness. After tightening the locknut, the adhesive can cure itself, and the looseness prevention effect is good. The disadvantage of this method is that the bolt rod can only be used once, and it is very difficult to disassemble. The bolt pair must be destroyed before disassembling.

The locknut is a nut, which is screwed together with the bolt or screw to play a fastening role. It is an original part that must be used for all production and manufacturing machinery. The locknut is a part that closely connects mechanical equipment. It can only be connected together through the internal thread, locknut and screw of the same specification. As required, we can tighten the locknut by the above locking methods.