1. Washer: a type of fastener with an oblate ring shape. It is placed between the supporting surface of bolts, screws or nuts and the surface of the connected parts, which increases the contact surface area of the connected parts, reduces the pressure per unit area and protects the surface of the connected parts from damage; another type of elastic washer, It can also play a role in preventing the nut from loosening.

2. Retaining ring: It can be installed in the shaft groove or hole groove of the machine and equipment to prevent the parts on the shaft or hole from moving left and right.

3. Pin: Mainly used for parts positioning, and some are also used for connecting parts, fixing parts, transmitting power or locking other fasteners.

4. Rivet: A type of fastener composed of two parts, a head and a nail shaft, used to fasten and connect two parts (or components) with through holes to make them into a whole. This type of connection is called rivet connection, or riveting for short. Belong to and non-detachable connection. Because to separate the two parts connected together, the rivets on the parts must be broken.

5. Assemblies and connection pairs: Assemblies refer to a type of fastener supplied in combination, such as a combination of machine screws (or bolts, self-supplied screws) and flat washers (or spring washers, lock washers); connection The secondary refers to a type of fastener supplied by a combination of certain special bolts, nuts and washers, such as the connection of high-strength large hexagonal bolts for steel structures.

6. Welding nails: Because of the heterogeneous fasteners composed of light energy and nail heads (or no nail heads), they are fixedly connected to a part (or component) by welding so as to be connected with other parts.

7. Bolt: A type of fastener consisting of two parts, a head and a screw (cylinder with external thread). It needs to be matched with a nut to fasten and connect two parts with through holes. This type of connection is called bolt connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

8. Stud: There is no head, only a type of fastener with threads on both ends. When connecting, one end of it must be screwed into the part with internal threaded hole, and the other end must be passed through the part with through hole, and then the nut is screwed on, even if the two parts are tightly connected as a whole. This type of connection is called a stud connection, which is also a detachable connection. It is mainly used in the occasions where one of the connected parts has a large thickness, requires a compact structure, or is not suitable for bolt connection due to frequent disassembly.

9. Nut: with internal threaded hole, the shape is generally flat hexagonal column, there are also flat square column or flat cylinder, with bolts, studs or machine screws, used to fasten the connection of two parts, make It becomes a whole.

10. Wood screw: It is also similar to machine screw, but the thread on the screw is a special rib for wood screw, which can be directly screwed into the wooden component (or part) to use a metal (or non-metal) with a through hole. The parts are firmly connected to a wooden component. This connection is also a detachable connection.

11. Screws: It is also a type of fasteners composed of two parts: the head and the screw. According to the purpose, it can be divided into three categories: machine screws, set screws and special purpose screws. Machine screws are mainly used for a tightening threaded hole part, and a fastening connection between a part with a through hole, no nut is required (this type of connection is called a screw connection, which is also a detachable connection; it can also be It is matched with a nut and is used for the fastening connection between two parts with through holes.) The set screw is mainly used to fix the relative position between the two parts. Special purpose screws, such as eyebolts, are used for lifting parts.

12. Self-tapping screws: similar to machine screws, but the thread on the screw is a special thread for self-tapping screws. It is used to fasten and connect two thin metal components to make them into a whole. Small holes need to be made in the component in advance. Because this kind of screw has high hardness, it can be directly screwed into the hole of the component. Form a responsive internal thread. This type of connection is also detachable.