An example of gear failure analysis

Gear is a kind of mechanical part that transmits motion and power. The type and characteristics of gear not only determine the running characteristics of gear, but also determine whether it will fail prematurely.

There are four types of gear failure:

(1) Wear failure refers to the material loss on the contact surface of gear teeth;

(2) Surface fatigue failure refers to the material failure caused by the contact surface or the stress under the surface exceeding the material fatigue limit. It can be further divided into initial pitting, destructive pitting and spalling.

(3) Plastic deformation failure refers to the surface deformation caused by the yield of surface metal under heavy load. It can be further divided into collapse and flash deformation, ripple deformation and groove deformation.

(4) Fracture failure refers to the fracture of the whole gear or a considerable part of the gear. It can be further divided into fatigue fracture, wear fracture, overload fracture, fracture caused by quenching or grinding cracks, etc.