1.Bolt: A type of fastener consisting of a head and a screw (a cylinder with external threads), which needs to be matched with a nut to fasten two parts with through holes. This connection form 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.
2.Stud: There is no head, only a type of fastener with external threads at both ends. When connecting, one end of it must be screwed into a part with an internally threaded hole, the other end must pass through a part with a through hole, and then screw on a nut, even if the two parts are tightly connected into one piece. This type of connection is called a stud connection, and it is also a detachable connection. It is mainly used in occasions where one of the parts to be connected has a large thickness and requires a compact structure, or where bolt connection is not suitable due to frequent disassembly.
3.Screw: It is also a type of fastener consisting of a head and a screw rod. It can be divided into three categories according to its use: machine screws, set screws and special purpose screws. Machine screws are mainly used for a fastened connection between a part with a fixed threaded hole and a part with a through hole, without the need for nut fit (this connection form is called screw connection, which is also a detachable connection; it can also be Cooperate with nuts for fast connection between two parts with through holes.) Set screws are mainly used to fix the relative position between two parts. Special-purpose screws, such as ring screws, are used for lifting parts.
4.Nut: with internal threaded holes, generally in the shape of a flat hexagonal column, and also in the shape of a flat square column or a flat cylinder, with bolts, studs or machine screws, used to fasten and connect two parts, making it a a whole.
5.Self-tapping screws: Similar to machine screws, but the threads on the screw are special threads for self-tapping screws. It is used to fasten and connect two thin metal components to make them into a whole. A small hole needs to be made on the components. Because of the high hardness of this kind of screw, it can be directly screwed into the hole of the component to make the component Responsive internal thread
6. Wood screw: It is also similar to the machine screw, but the thread on the screw rod is a special wood screw thread, which can be directly screwed into a wooden component (or part), and is used to put a metal (or non-metal) with a through hole. Parts are fastened together with a wooden member. This connection is also a detachable connection.
7.Washer: A type of fastener in the shape of an oblate ring. Placed between the supporting surface of the bolt, screw or nut and the surface of the connected part, it plays the role of increasing the contact surface area of the connected part, reducing the pressure per unit area and protecting the surface of the connected part from being damaged; another type of elastic washer, It can also play a role in preventing the nut from loosening.
8.Retaining ring: It is installed in the shaft groove or shaft hole groove of the machine and equipment, and plays the role of preventing the parts on the shaft or hole from moving left and right.
9.Pin: Mainly used for positioning parts, some can also be used for connecting parts, fixing parts, transmitting power or locking fasteners.
10.Rivet: A type of fastener consisting of a head and a shank, used to fasten and connect two parts (or components) with holes to make them a whole. This form of connection is called a rivet connection, or riveted for short. It is a non-detachable link. Because if the two parts that are connected together are separated, the rivets on the parts must be broken.
11.Components and connection pairs: Assemblies are a type of fastener supplied in combination, such as a combination of some machine screws (or bolts, self-supplied screws) and flat washers (or spring washers, lock washers); A type of fastener that combines certain special bolts, nuts and washers, such as high-strength large hexagon head bolts for steel structures.
12.Welding stud: A heterogeneous fastener consisting of a nail shank and a nail head (or no nail head), which is fixedly connected to a part (or component) by welding to connect with other parts.
