Usually three sets of hexagon socket screws are sent to the customer from the factory. In this production process, we need to carry out quality inspection on the three sets of screws of the cup head. This will ensure the quality of the fixing screws. In this way, customers can use the No. 1 combination screw with greater confidence.
Bolts are widely used as connection parts.The use environment of locomotives, aerospace, and wind turbines is mostly high strength and high stress, while the use environment of main components of passenger cars is mostly low stress cycle, but still There are great hidden dangers. From a safety point of view, the parts connected by the bolts are very expensive. Therefore, when bolts fail, it is not only the bolts themselves that are damaged, but the entire product.
Bolt connection is an important application in automobile assembly. According to relevant information, according to the threaded fasteners on the engine, there are usually about 1500 to 2000 pieces, and the variety is up to more than 100. The specifications also range from M6 to M30, of which About 100 are closely related to the safety performance of the vehicle. As the selection of the most important bolt specifications and pre-tightening forces in the assembly process, there are theoretical deficiencies and misunderstandings.
As an important connection, bolts must be tightened when the assembly is installed. Before the connection is subjected to a working load, it is subject to a force in advance. This pre-applied force is the pre-tension; the purpose of the pre-tension is to enhance the reliability of the connection. And tightness, to prevent the assembly mounting parts from being subjected to forces during work, and gaps or relative slippage between the connecting parts will occur.Therefore, in the design of the assembly, the size of the pretension force must be standardized. .