I. Friction-based anti-loosening: This method increases friction by increasing the normal pressure between the threads, preventing relative rotation.
1. Spring washer: Utilizes elasticity to generate additional pressure, increasing friction. Low cost, but limited anti-loosening ability.
2. Self-locking nut: Contains an internal nylon ring or a constricting structure. Deformation during tightening generates friction, providing reliable anti-loosening.
3. Double nut: Two nuts are tightened against each other, generating pressure between the contact surfaces, increasing friction.
II. Mechanical anti-loosening: This method directly restricts nut rotation through locking elements, providing reliable anti-loosening.
1. Cotter pin and slotted nut: After tightening the nut, insert the cotter pin and pry open the tail. This is the most reliable anti-loosening method.
2. Locking washer: The inner wing of the washer engages with the screw groove, and the outer wing fits tightly against the side of the nut. This provides reliable anti-loosening.
3. Connecting wire: A steel wire is threaded through the holes in the heads of multiple bolts, connecting them in series to restrain each other. Suitable for group threaded connections. III. Permanent Anti-Loosening This method achieves permanent anti-loosening by disrupting the rotational flexibility of the threaded joint. Disassembly typically damages the parts.
1. Spot Welding Anti-Loosening: Spot welding the exposed portions of the nut and bolt together.
2. Punching Anti-Loosening: Using a punch to create a point at the engagement point between the screw and nut, disrupting the threads.
3. Adhesive Anti-Loosening: Applying an anaerobic adhesive or similar bonding agent to the threaded engagement area, allowing it to cure and bond together.
