Fasteners usually include the following 12 types of parts:
1. Bolt: A type of fastener consisting of a head and a threaded rod (cylindrical body with external threads), which is required to cooperate with a nut and is used to fasten two parts with through holes. This type of connection is called a bolted 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: A type of fastener without a head that is only threaded at both ends. When connected, one end must be screwed into the part with the internally threaded hole and the other end through the part with the through hole, and then screw on the nut even if the two parts are fastened and connected in one piece. This type of connection is called a stud connection and it is also a detachable connection. It is mainly used for occasions when one of the connected parts has a large thickness, requires a compact structure, or is frequently used for bolting because of frequent disassembly.
3. Screw: It is also a type of fastener composed of two parts of the head and the screw. It can be divided into three categories according to the purpose: machine screws, set screws and special purpose screws. The machine screw is mainly used for a part with a tight threaded hole, and a fastening connection with a part with a through hole, and does not require a nut to fit (this type of connection is called a screw connection and is also a detachable connection; it can also be Fits with a nut for fastening connections between two parts with through holes.) Set screws are used to fix the relative position between two parts. Special-purpose screws such as eyebolts are used for lifting parts.
4. Nuts: With internal threaded holes, the shape is generally flat hexagonal, cylindrical or flat cylindrical, with bolts, studs or machine screws, used to fasten two parts, so that It becomes a whole.
Special category of nuts
High-strength self-locking nut
A classification of self-locking nuts, with high strength and reliability. It is mainly the introduction of European technology as a prerequisite for the use in road construction machinery, mining machinery, vibration machinery equipment, etc. Currently, there are very few domestic manufacturers of such products.
Nylon self-locking nut
Nylon self-locking nut is a new high-vibration anti-loosening and loose-fastening part, which can be applied to various mechanical and electrical products with a temperature of -50 to 100°C. At present, the demand for nylon self-locking nuts has increased dramatically in aerospace, aviation, tanks, mining machinery, automobile transportation machinery, agricultural machinery, textile machinery, electrical products, and various types of machinery. This is because its anti-vibration and anti-loosening performance is greatly increased. For various other
Anti-loosening device, and the vibration life is several times or even tens of times longer. More than 80% of accidents in the current machinery and equipment are caused by the loosening of fasteners, especially in mining machinery.
The use of nylon self-locking nuts can eliminate major accidents caused by loose fasteners.
5. Self-tapping screws: Similar to machine screws, but the thread on the screw is a special thread for tapping screws. It is used to fasten and connect two thin metal components into a single piece. The small holes need to be made in advance on the components. Because the screws have a high hardness, they can be screwed directly into the holes of the components to make the components Responsive internal threads are formed. This type of connection is also a detachable connection.
6. Wood screws: similar to machine screws, but the thread on the screw is a dedicated wood screw thread that can be screwed directly into a wooden member (or part) for the metal (or non-metal) with a through hole The parts are fastened together with a wooden member. This connection is also a detachable connection.
7. Gasket: A type of fastener that is oblate in shape. Placed between the supporting surface of the bolt, screw or nut and the surface of the connecting part, play the role of increasing the contact surface area of the connected parts, reducing the pressure per unit area and protecting the surface of the connected parts from being damaged; another type of elastic gasket, Can also play a role in preventing the nut from loosening.
8. Retaining ring: It is installed in the shaft groove or hole groove of the machine and equipment and plays the role of blocking the left and right movement of the part on the shaft or hole.
9. Pin: mainly used for positioning of parts, and some can also be used to connect parts, fix parts, transmit power or lock other fasteners.
10. Rivet: A type of fastener consisting of a head and a shank that is used to fasten parts (or components) that connect two through-holes to make it a unitary piece. This type of connection is called rivet connection, or simply riveting. Generic and non-detachable connection. Because the two parts that are connected together must be separated, the rivet on the part must be destroyed.
11. Assembly and connection pair: The assembly refers to a type of fastener [4] that is supplied in combination, such as combining a machine screw (or bolt, self-provided screw) with a flat washer (or spring washer, lock washer). Supply; connection vice refers to a certain kind of special bolts, nuts and washers to provide a combination of fasteners, such as steel structure with high-strength large hex head bolts.
12. Weld nails: Because of the different types of fasteners made up of light energy and nail heads (or no nail heads), they are fixedly attached to a part (or component) by welding so that they can be connected to other parts.
13. Wire thread inserts: Wire thread inserts are a new type of threaded connection element made from high-strength, high-precision corrosion-resistant diamond-shaped wire. Shaped like a spring, it is installed in a special screw hole of the base body. The inner surface forms a standard thread. When combined with a screw (bolt), the thread connection strength and wear resistance can be significantly improved; especially in aluminum, magnesium, cast iron, plastic and other low strength On the material. Shrinking type is to add one or several rings of tightening ring on the basis of common type. Xinxiang Yongda Industry Co., Ltd. is a professional manufacturer of wire thread inserts. It is recommended that the wire inserts be embedded in the threads of low-strength engineering materials such as aluminum, magnesium alloys, cast iron, glass steel, and plastics to form standard M and MJ threads. Continuous strength, impact resistance and wear resistance, and can disperse the stress protection matrix thread, greatly extending the life of the matrix. At the same time, the stress of the thread is improved, and an elastic connection is formed. The pitch and half-angle error between the internal and external threads are eliminated, the load on the thread is evenly distributed, and the thread of the base body is protected from being damaged and the service life is prolonged.