1, tooth surface wear

For gear gear transmission or containing lubricating oil is not clean, because of the relative sliding engagement between the tooth surface, make some hard abrasive particles into the friction surface, so that the tooth profile change, increase the gap, so that the gear tooth breaking leads to excessive thinning. In general, the abrasive wear on the tooth surface is only caused by the inclusion of abrasive particles in the lubricating oil.

2, tooth surface gluing

For the high speed and heavy load gear transmission, because of the large friction between teeth, the relative velocity, the meshing temperature is too high, once the bad lubrication, the oil film between the tooth surface will disappear, making direct contact with the metal surface of two teeth, which are bonded to each other. When the two tooth surface to relative movement, hard tooth surface will be part of the material is soft on the tooth surface along the sliding direction and the formation of tore grooves.

3 fatigue pitting corrosion

Two teeth meshing contact force between the tooth surface, and the reaction to the contact stress on the surface of two, due to the meshing point position is changed, and the gear is periodic motion, so the contact stress is according to the pulse cycle change. In such a long time alternating tooth surface contact stress on the tooth surface, the marks will appear small cracks, with the passage of time, the cracks in the surface gradually and the lateral extension of crack to form a ring, so that the tooth surface of small area in the formation of some shallow fatigue spalling.

4, broken teeth

The loading gear in the operation of the project, as the cantilever beam, the root by the fatigue limit of the periodic pulse stress exceeds the gear material, will produce cracks in the roots, and gradually expanded, the remaining part is unable to withstand the transmission load occurs when the broken teeth phenomenon. The gear may cause tooth breaking because of its severe impact, unbalanced load and uneven material.

5, teeth plastic deformation

Under the impact load or heavy load, the tooth surface is prone to local plastic deformation, so that the surface of the involute tooth profile is deformed.