Dongming fasteners refer to the general term for mechanical parts used when two or more parts (or parts) are fastened together. A screw is a general term for a fastener, an everyday word of mouth. Also called fasteners. Standard products refer to products for which national standards and industry standards have been formulated in terms of manufacturing, size, inspection, etc. The manufacturer manufactures molds accordingly and produces them with running water. Those that do not belong to the category of standard products are non-standard products. Then, let's understand the concept and classification of Dongming fasteners together!

Contents of Dongming Fasteners:

Dongming fasteners are mainly other parts that the state has not formulated strict standard specifications, no relevant parameter regulations, and other parts that are freely managed by enterprises. In addition to standard parts, there are many varieties, and there is no standardized classification at present. Generally, enterprises develop independently according to market demand and the development of their own brands to extend the vitality of products.

Types of Dongming Fasteners

Dongming fasteners mainly include bolts, studs, screws, nuts, self-tapping screws, wooden screws, washers, retaining rings, pins, rivets, components and fastener pairs, welding nails, etc.

(1) Bolt: a fastener consisting of a head and a screw (a cylinder with an external thread), which needs to be fastened with a nut to fasten two parts with through holes. This form of connection is called a bolted connection. After removing the nut from the bolt, the two parts can be separated, so the bolted connection is a removable connection.

2) Rod end: a fastener without a head, only with external screws at both ends. When connecting, you need to screw one end into the part with the female threaded hole, pass the other end through the part with the through hole, and then screw in the nut. It doesn't matter if the two parts are fastened together. This form of connection is called a rod end connection and is a detachable connection. It is mainly used in a situation where the thickness of the fastened part is large and the structure is required to be compact, as well as the situation where the disassembly is frequent and the bolt tightening is not ideal.

3) Screw: It is also a fastener composed of a head and a screw. According to the purpose, it can be divided into three types: steel structure screw, fastening screw and special purpose screw. Machine screws are mainly used to fasten parts with threaded holes, and are used to fasten parts with through holes without nut matching. (This type of fastening is called threaded fastening, and it is also detachable fastening. Together with the nut, it can also be used for fastening between two parts with through holes.) Set screws are mainly used to fix two relative position between parts. Special purpose screws include eyebolts, etc., which are used to hoist parts.

4) Nut: There are internal threaded holes, and the shape is generally flat hexagonal, but it can also be flat quadrangular or flat cylindrical. It is used with bolts, studs or steel frame screws to fasten the two parts together. .

5) Self-tapping screws: Similar to screws, but the screws on the screws are dedicated self-tapping screws. In order to fasten the two thin metal parts together to make them one, small holes need to be pre-made in the parts. Due to the high hardness of the screw, it can be directly screwed into the hole of the component to form a corresponding internal thread on the component. This form of connection is also a detachable connection.

6) Wood screws: Also similar to screws, but the screws on the screws are screws for special wood screws, which can be directly screwed into wooden parts (or parts), used to connect a through-hole metal (or non-metal) part with a wooden part fastened together. This connection is also a detachable connection.

7) Gasket: Flat circular fastener. Placed between the bearing surface of the bolt, screw or nut and the surface of the connecting part, it can increase the contact surface area of ​​the connected parts, reduce the pressure per unit area, and protect the surface of the connected parts from damage; another elastic washer also To prevent the nut from loosening.

8) Retaining ring: It is installed in the shaft groove or hole groove of steel structure and equipment to prevent the left and right parts on the shaft or on the hole.

9) Pin: mainly used for part positioning, but also for part connection, part fixing, power transmission or other fastener locking.

10) Rivet: A fastener consisting of a head and a nail rod, which connects parts (or components) with two through holes into one. This form of connection is called rivet connection, or riveting for short. is a non-removable connection. Because to separate the two connected parts, it is necessary to break the rivets of the parts.

11) Assembly parts and connecting pairs: Assembly parts refer to a kind of fasteners supplied together, such as a combination of machine screws (or bolts, self-feeding screws) and flat washers (or spring washers, lock washers); Connection pair refers to the type of fasteners supplied by a combination of special bolts, nuts and washers, such as high-strength hexagon head bolt connection pairs for steel structures.

12) Welding nails: dissimilar fasteners consisting of an optical axis and a nail head (or no nail head) are fixedly connected to a part) or parts by welding, and are reconnected with other parts.

The above is the concept and classification of Dongming fasteners. If you want to know more, please feel free to contact us!