Classification of fasteners

Fasteners are a general term for a class of mechanical parts used when fastening two or more parts (or components) into a whole. It is also often referred to as a standard part in the market. There are many types of fasteners, mainly including the following categories:.

Bolt: consists of a head and a screw (a cylinder with external threads), which need to be matched with the nut for fastening and connecting two parts with through holes. Bolted connections are removable connections.

● Stud: there is no head, only both ends are externally threaded. When connecting, screw one end into the part with internal thread hole, and the other end through the part with through hole and screw the upper nut to achieve tight connection. Stud connections are also removable connections.

Screw: composed of head and screw, according to the use can be divided into machine screws, set screws and special purpose screws. Machine screws are mainly used to tighten thread holes and Connections between parts through holes; The setting screw is used to fix the relative position of the two parts; Special purpose screws such as ring screws are used to lift parts.

Nuts: With internal threaded holes, with bolts or studs, used to fasten the connecting parts.

Tapping screw: similar to the screw, but the thread on the screw is a special self-tapping thread, which can be directly screwed into the metal component with a small hole in advance to form an internal thread and tighten the connection.

● Wood screw: The thread on the screw is a special wood screw thread, which can be directly screwed into the wooden component for fastening the connection of metal (or non-metal) parts and wooden components.

● Washer: flat ring fastener, between the support surface of the bolt, screw or nut and the surface of the connecting part, increase the contact area, reduce the unit area pressure and protect the surface of the part.

● Stop ring: used to stop shaft or hole. Fastener where the upper part moves from side to side.

● Pin: Used for parts positioning, connecting, fixing or transmitting power.

● Rivet: composed of head and nail rod, through riveting to achieve the tight connection of two parts with a pass hole, for non-removable connection.

● Assemblies and connection pairs: fasteners supplied in combination, such as screws and washers supplied in combination, or special bolts, nuts and washers supplied in combination.

● Welding nails: fasteners that are fixed on other parts by welding in order to be connected with other parts.