Analysis of the reasons for the loosening of high-strength bolts

When the high-strength bolts loosen, it will generate a lot of mechanical energy, which directly acts on the high-strength bolts and equipment, causing the high-strength bolts to be damaged. After the high-strength bolts are damaged, the equipment cannot work normally, further causing damage to the equipment. The external thread of the standard part subjected to axial force is destroyed and the bolt is destroyed. Under the action of tangential force, the bolt is laser cut and the bolt hole is oval in the standard part. At this stage, the reasonable fastening method is Down's external thread standard parts to prevent loosening and loosening. The process of Down has the characteristics of the process of up and down. It can be used in conjunction with the upper and lower processes. The connection uses nuts with two different directions of rotation. The nuts on the supporting surface during work are called tightening nuts, and the nuts on the non-supporting surface are called lock nuts. Before the lock nut is torqued, the lock nut is pre-tightened. In case of shock and impact, the tightening nut will loosen. However, since the release direction of the tightening nut is the tightening direction of the tightening nut, tightening the locking nut can only prevent the tightening nut from loosening, thereby causing the tightening nut to be invalid. The high-strength bolt connection has the advantages of simple structure, excellent physical performance, detachable type, strong resistance, and not easy to loosen under dynamic load. It's also a great way to connect. The high-strength bolt is a unique wrench used to tighten nuts, which creates extreme and controllable preload. Through the nut and the buffer plate, the same size of pre-pressure is formed on the connecting member. Under the effect of pre-stress tension, the contact area of ​​the joint will produce a lot of friction. Obviously, as long as the axial force is lower than its own friction, the parts will not loosen and the connection will not be damaged. This is also the basic principle of high-strength bolt connection. High-strength bolted connections rely on the understanding of friction between the surface layers of the connectors to prevent them from rolling. In order to better make the contact area have sufficient friction, it is necessary to strengthen the locking force of the prefabricated components and the friction of the contact area. The clamping force between components is achieved by torque bolts, so the bolts must be made of high-strength steel plates, which is also called high-strength bolt connection. In high-strength bolted connections, the level of friction has a greater effect on its bearing capacity. The test results show that the friction resistance is mainly affected by the shape of the contact area and the material of the module. In order to better improve the friction resistance of the contact area, sand blasting and steel brush cleaning are usually used to solve the contact area of ​​the parts in the connection area.