Bolt loosening is a common problem for bolted joints under vibration and dynamic load. It may lead to connection failure and safety hazard.
Vibration is the primary cause. Repeated alternating force makes nut rotate gradually. Multiple anti-loosening solutions are available. Lock nuts, spring washers, nylon insert lock nuts are widely used passive anti-loosening parts.
For heavy vibration equipment, thread adhesive is another option. But disassembly becomes difficult after glue application. Choose proper anti-loosening method according to vibration level, maintenance requirement and working temperature.