Bolt and nut assembly realizing fit fastening

The invention discloses a bolt and nut assembly realizing fit fastening. The bolt and nut assembly comprises a bolt and a nut, wherein the bolt is a hexagonal bolt and comprises a screw head and a screw rod which are connected with each other. The screw head is a hexagonal screw head with an orthohexagonal section. One side of the screw head is connected with the screw rod. The screw rod is divided into two layers. A center shaft part is a metal layer covered with a rubber layer. The rubber layer has a smooth surface and is free of threads on the surface, and the tail section part of the screw rod is comparatively thin. The nut is a hexagonal nut matched with the bolt. Threads are formed on the inner surface of a center through hole of the nut and adopt sharp cutting edges. The threads of the nut can be embedded into the surface rubber of the screw rod for fastening attachment. According to the scheme, the bolt and nut assembly is novel in structure, the screw rod of the bolt is covered with the smooth rubber layer that replaces threads on a common screw rod, the threads on the nut are sharp and can be tightly embedded into the rubber, the fastening attachment of the bolt and the nut is effectively facilitated, and the bolt and nut assembly is tighter and firmer in use and has certain economic benefits and market prospect.