1, Shearer cutting unit rocker gearbox is not like the general type of fixed installation, but with the shearer cutting unit as a whole up or down tilt, and with the shearer production process needs and back and forth movement;

2, uneven load gear arm, at any time may be from large coal, gangue or misoperation caused by factors such as rocker arm momentarily huge impact;

3, shearer vibration source and more motor vibration (such as cutting motor, traction motor, etc.), arm gearbox vibration, traction gearbox vibration, shearer walking and scraper conveyor gear rack meshing vibration, face Unequal factors Cross-vibration affect the rocker arm gearbox vibration.

4, fully mechanized face coal dust production and dust spray water and other harsh production environment.