It is important to distinguish the type of fasteners from the fasteners to achieve the removable parts of the connection, is to enhance the mechanical maintenance of important measures. To meet the different functional requirements, there are many types of fasteners.

The common problem in maintenance is the lack of awareness of the fasteners, the disassembly is not classified but kept casually thrown together, or after the injury with the use of injury, or free to replace, and thus repair the progress or reliability of adverse effects; Moreover, the assembly does not pay attention to distinguish between the type of thread, blind match. Such as maintenance in the face of a lot of aluminum scrap parts of the situation, are due to the unequivocal use of the same thickness but different teeth of the steel bolts to the aluminum alloy parts of the screw hole in the strong push hard, and so found The thread of the screw hole has been destroyed.

In many cases, this damage is not easy to repair or can not repair, and thus had to carry out a wider range of repair or replacement. Even if the repair (such as reaming, tapping, etc.), it is bound to reduce the reliability and life of parts. Therefore, it is important to carefully distinguish the type of fasteners in maintenance.