What is Fastener
Fasteners are a type of mechanical parts that are used for fastening connections and are extremely widely used. Fasteners are used in a wide range of industries, including energy, electronics, electrical appliances, machinery, chemicals, metallurgy, molds, hydraulics, etc., in various machinery, equipment, vehicles, ships, railways, bridges, buildings, structures, tools, instruments All kinds of fasteners can be seen on, chemicals, instruments and supplies, etc., which are the most widely used mechanical basic parts.
It is characterized by a wide variety of specifications, different performance and uses, and a high degree of standardization, serialization, and generalization. Therefore, some people call a type of fasteners that have national standards as standard fasteners, or simply standard parts.
Fasteners are a type of mechanical parts that are used for fastening connections and are extremely widely used.
All kinds of fasteners can be seen on various machinery, equipment, vehicles, ships, railways, bridges, buildings, structures, tools, instruments, meters and supplies. It is characterized by a wide variety of specifications, different performance and uses, and a high degree of standardization, serialization, and generalization. Therefore, some people call a type of fasteners that have national standards as standard fasteners, or simply standard parts. Fasteners are the most widely used mechanical basic parts. With my country’s accession to the WTO in 2001, it has entered the ranks of major international trading nations. my country’s fastener products are exported to various countries in the world, and fastener products from all over the world are also pouring into the Chinese market. Fasteners, as one of the products with a large import and export volume in China, are in line with international standards. It is of great practical significance to promote Chinese fastener companies to the world and promote fastener companies to fully participate in international cooperation and competition. Strategic significance. Due to the specifications, dimensions, tolerances, weight, performance, surface conditions, marking methods of each specific fastener product, as well as the specific requirements for acceptance inspection, marking and packaging items
It usually includes the following 12 types of parts:
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.
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 pass through the part with through hole, and then screw the nut, 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 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.
It is also a type of fastener composed of two parts: head and screw. According to the purpose, it can be divided into three categories: machine screws, set screws and special purpose screws. The machine screw is mainly used for a tightening connection between a part with a threaded hole and a part with a through hole, without the need of a nut (this connection form is called a screw connection, which is also a detachable connection; Cooperate with nut, used for fastening connection between two parts with through holes.) Set screw is mainly used to fix the relative position between two parts. Special purpose screws such as eyebolts are used for lifting parts.
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 and connect two parts to make it One piece whole.
Similar to machine screws, but the thread on the screw is a special self-tapping screw thread. It is used to fasten and connect two thin metal components 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
It is also similar to machine screw, but the thread on the screw is a special wood screw thread, 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.
A type of fastener with an oblate ring shape. It is placed between the support 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 prevent the nut from loosening.
It can be installed in the shaft groove or shaft hole groove of the machine and equipment to prevent the parts on the shaft or hole from moving left and right.
It is mainly used for positioning the left and right parts, and some can also be used for connecting parts, fixing parts, transmitting power or locking fasteners.
A type of fastener composed of two parts, a head and a nail shaft, used to fasten and connect two parts (or components) with holes to make them into a whole. This type of connection is called rivet connection, or riveting for short. It is a non-detachable link. Because if the two connected parts are separated, the rivets on the parts must be broken.
Assembly and connection pair
Assemblies are 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); the connection pair refers to A type of fastener supplied with a combination of special bolts, nuts and washers, such as the connection of high-strength large hexagon bolts for steel structures.
Heterogeneous fasteners composed of nail rods and nail heads (or no nail heads), which are fixedly connected to a part (or component) by welding so as to be connected with other parts.