1、Non detachable anti-loosening

The use of mechanical fixings so that the threaded parts and the connection between or between the threaded parts and threaded parts fixed and pinned to stop the loosening.The advantage of this method is to prevent the loosening of reliable, its anti-loosening reliability generally depends on the mechanical fixings (or fasteners themselves, such as slotted nuts) static strength or fatigue strength.Its disadvantage is to increase the weight of the fastening connection, manufacturing and installation trouble, can not be motorized installation, so the cost is higher.Due to its high anti-loosening reliability, it is still widely used in some important parts of mechanical products and aerospace products.-Glue-coated screws

Punch point riveting of bolt (or screw) head and nut end face: After tightening, the method of punch point riveting is used to make the bolt (or screw) nut produce local deformation and stop it from loosening each other.

Locking adhesive bonding: in the matching thread surface coated with epoxy resin or anaerobic adhesive, adhesive curing can be firmly bonded to the matching threads, to achieve the purpose of locking anti-loosening.Different adhesives often have different locking ability.Epoxy coated fasteners, the bond strength is very high, is not removable.Coated with anaerobic adhesive fasteners, although removable, but after disassembly of the thread surface residual adhesive is difficult to clean, and the thread may be damaged, fasteners should not be used again.

Adhesives can also be used as sealing materials for threads, but they cannot withstand high temperatures.The best adhesives can work at a temperature of 230 ℃; the worst adhesives, its working temperature is only 94 ℃.

2、Increase the friction of anti-loosening

Increase the friction between the threads or the head of the bolt (screw) and the end face of the nut or increase the friction between the two at the same time to achieve the purpose of anti-loosening.Its biggest advantage is not subject to the limitations of the use of space, can be repeatedly installed and disassembled for many times, can be motorized assembly, this anti-loosening method in the machinery manufacturing sector and aerospace field is the most widely used.Anti-loosening screws