Self-locking nut

The utility model discloses a self-locking nut which comprises a nut body and a sealing cover which is arranged outside the nut body. The nut body comprises a supporting plate, a shell nosing section and threads, wherein the threads are arranged inside the nut body, a sealing gasket is arranged at the bottom of the supporting plate, a sealing ring is sleeved outside the shell nosing section, and both the sealing ring and the sealing gasket are made of high and low temperature resistant silicon rubber. The supporting plate is additionally arranged on the basis of a normal dual-lug-swimming self-locking nut, the specially-made silicon rubber sealing ring and the specially-made silicon rubber sealing gasket are used, the sealing cover, the sealing ring and the sealing gasket are matched with one another and used, therefore, the self-locking nut is reasonable in structure, higher and more stable in strength when being connected with a box body, and capable of greatly improving reliability of installation, meanwhile having good anti-vibration, anti-loose, high-and-low-temperature-resistant and corrosion-resistant performance, effectively providing guarantee for hydraulic systems, air pressure systems and oil way systems of the fields of aviation, aerospace, ships and railways, having good economic benefits and social benefits, and being widely popularized and applied in a mechanism equipment industry.