A nut, as a crucial fastener, has the core function of working in conjunction with a bolt to achieve a secure connection between objects. It typically has internal threads that match the external threads of the bolt. By rotating the bolt, the nut and bolt are tightly engaged, thus achieving a fastening effect.
Nuts come in many varieties, classified into different types based on their use and design characteristics. Hex nuts are the most common type, their hexagonal shape facilitating rotation with a wrench or socket. Locking nuts, through special designs such as nylon inserts or deformed threads, prevent loosening in vibrating or impact environments. Self-locking nuts utilize the pre-tension force generated by springs or elastic elements to achieve automatic locking, suitable for applications requiring high reliability.
The working principle of a nut is based on the mechanical properties of threads. When a bolt is screwed into a nut, the frictional force between the threads generates a resistance torque. This resistance torque balances the torque required to rotate the bolt, thus preventing the bolt from loosening under stress. At the same time, pressure is generated on the contact surface between the nut and the connected parts. This pressure distribution makes the connection more stable and able to withstand greater external forces.