Failure is a common problem of mechanical equipment. It is not equal to failure, but loses its original effectiveness and cannot work normally after failure. The failure is mainly due to the gear failure caused by improper use or aging of the machine. Correct use is a necessary condition for prolonging the service life of gears. The failure forms of gears include the following:
1) Tooth surface wear: due to the relative sliding between meshing tooth surfaces, some hard abrasive particles enter the friction surface, which changes the tooth profile and increases the side clearance. Finally, the gear is too thin, resulting in tooth fracture. This can be seen in open gear drives and closed drives containing unclean lubricating oil.
Why does the gear fail
2) Tooth surface gluing: the tooth surface friction is large and the meshing relative speed is fast, resulting in too high temperature in the meshing area. Once the lubrication conditions are poor, the oil film between the tooth surfaces will disappear and the surface will be in direct contact, resulting in mutual bonding. When the two tooth surfaces continue to move relative to each other, the harder tooth surface will tear off some materials on the softer tooth surface and form grooves. This situation can be seen in gear transmission with high speed and heavy load.
3) Plastic deformation of tooth surface: under impact load or heavy load, the tooth surface is easy to produce local plastic deformation, resulting in the deformation of the curved surface of involute tooth profile.
