How many self-locking nuts do you know?

　　Tightening and anti loosening - "Anti loosening" refers to the ability to resist external impacts, vibrations, or variable loads after normal tightening of threaded connections, as well as the ability to weaken the connection performance when subjected to high temperatures or large temperature changes, rather than comparing the torque displayed when manually loosened.

　　And self-locking nuts are widely used in industries such as mechanical manufacturing because they can effectively prevent loosening of connections. With the continuous development of technology, there are more and more types of self-locking nuts,

　　Today, through this article, I will show you Laotie: What kinds of self-locking nuts and their characteristics are there? You are also welcome to add Laotie.

　　1、 Nylon insert self-locking nut

　　Nylon insert self-locking nut is a very common self-locking nut with a wide range of applications. Structurally, the nylon ring is embedded into the nut head. Its working principle is that when the non-metallic embedded nut is tightened, the thread of the bolt will naturally squeeze into a spiral on the nylon ring, forming a tight fit with the bolt thread, and generating frictional resistance under the elastic force of nylon to achieve the purpose of preventing loosening.

　　Nylon embedded self-locking nuts have a simple structure, reliable anti loosening performance, and tightening will not damage the nut body. They are also very suitable for use in places with vibration loads. Reusable, as the number of uses increases, the anti loosening properties will weaken,

　　Screw Jun referred to relevant technical materials and research has shown that the recommended usage of this nut should not exceed 5 times. Due to the weak heat and acid alkali resistance of nylon, it is suitable for use in the temperature range of -50 ℃ to 100 ℃, and the application environment should avoid acid and alkali.

　　2、 Metal self-locking nut

　　Metal self-locking nuts are also a commonly used structure, as shown in the following diagram.

　　The working principle of metal self-locking nuts is to create an interference fit between the threads by adjusting the deformation of the threaded bottom hole or thread profile when fitting with the bolt, thereby increasing the friction between the threads and achieving the purpose of anti loosening.

　　Metal self-locking has good anti loosening performance and a simple structure. Compared to nylon self-locking nuts, its application environment requirements are lower, making it suitable for use in high temperature, acid and alkali corrosive environments. Because the deformation ability of metal is relatively poor compared to nylon, even if the size deviation of the parts is small, their torque characteristics will deviate greatly. Therefore, its size control accuracy requirements are also high, and it is not suitable for application in places with high vibration loads.

　　Overall, its anti loosening performance is better with nylon self-locking nuts, and the tightening torque is also higher when tightened. Screw Jun referred to relevant standards and learned that it is recommended to reuse it no more than 5 times.

　　3、 Shibiluo self-locking nut

　　The Shibilao self-locking nut has an innovative self-locking internal thread profile structure, with a unique 30 ° wedge-shaped slope at the root of the thread. Due to the change in the angle of the tooth shape, the normal force generated on the indirect contact surface of the thread forms a 60 ° angle with the bolt axis, which generates a much larger frictional force when the axial clamping force is transmitted to the thread contact area of the bolt and nut than ordinary threads, effectively improving the anti loosening performance.

　　In accordance with the thread structure characteristics of the Spiro nut, the thread tip of the Spiro bolt is designed as a 30 ° wedge-shaped surface that cooperates with the thread of the Spiro nut. This structural design changes the thread contact from the previous linear contact to a strip surface contact, improving the stability of the contact. Thus, the clamping force remains constant.

　　In addition to providing superior anti loosening performance, it can also prevent tooth slippage, prevent bolt fracture, prevent detachment, and resist over torsion, making it a new type of highly reliable bolt pair.

　　The self-locking nut of Shibilao has good anti loosening performance, can be reused, and has high efficiency, especially suitable for use under various temperature and impact vibration conditions. But the thread structure is relatively complex and the cost is relatively high, so it has not been widely used in the manufacturing industry yet.

　　4、 Flange toothed self-locking nut

　　The bearing surface of the flange with self-locking nuts is uniformly distributed with a certain angle of "sawtooth" or arc-shaped teeth. The clamping force generated during the tightening process causes the teeth to embed into the surface of the connecting surface, thereby increasing the friction force of the bearing surface and playing a good anti loosening role.

　　This type of nut is generally suitable for applications with low strength of the opponent's parts. The tooth profile of the flange nut can be smoothly pressed into the opponent's part and form a tooth profile on the opponent's part.

　　Taking automobiles as an example, lightweight materials such as aluminum alloy and magnesium alloy are becoming increasingly widely used, and flange toothed self-locking nuts are very suitable for these materials.

　　5、 Tang self-locking nut

　　The following diagram shows the anti loosening method of Tang's self-locking nut. When connecting, two nuts with different rotation directions are used: the nut on the working support surface is called the fastening nut, and the nut on the non support surface is called the locking nut. Pre tighten the fastening nut before using the locking nut.

　　Tang bolts are compatible with two types of nuts with different rotation directions, allowing friction and tightening forces to be converted into each other and achieve the purpose of restraint. The loosening force of the right-handed nut was directly converted into the tightening force of the left-handed nut, and the two opposing forces were transformed into complementary forces, inventing a truly non loosening threaded structure.

　　From the perspective of threads, eccentric nuts still belong to traditional threads, which are a type of "single rotation, continuous, and equal cross-section" thread, while Down's threads are a type of "double rotation, discontinuous, and variable cross-section" thread, completely breaking through the concept of traditional threads and being a major breakthrough in the field of threads.

　　The anti loosening of fasteners is an important research topic in the industry. For connection positions that bear alternating loads and shear loads, certain anti loosening measures need to be taken, and self-locking nuts are a common way of anti loosening.

　　Each self-locking nut has its own application characteristics, for example, nylon insert self-locking nuts are suitable for use in connections with certain impact loads and have low cost. Flange with toothed self-locking nut, suitable for use in light metal connections. I hope it can provide some enlightenment and reference for Laotie in searching for anti loose methods.