Common reasons for broken teeth of excavator slewing bearing failure


①The slewing bearing for excavator is an important joint of the excavator. It fails during the use of Sealed Spherical Roller Bearings ( https://www.sanyabearing.com/product/spherical-roller-bearings/ ). The user does not know the reason. There are two main reasons for the early failure of the slewing bearing for excavators. One is broken teeth; The second is raceway damage. Among them, broken teeth are the main reason, accounting for more than 90%, and most of them occur within six months after the excavator leaves the factory, and the broken teeth cause the failure of the excavator turntable bearing. Broken teeth generally do not appear in the early normal use of slewing bearings. However, we have to face the fact that the working conditions of excavators are worse than those of the main engine in most other industries such as tower cranes and automobile cranes that use bearings. , the rotation speed is faster, the impact load is also larger, and the possibility of broken teeth is correspondingly larger.

②The law of early broken teeth of Thrust Cylindrical Roller Bearings ( https://www.sanyabearing.com/product/cylindrical-roller-bearings/ ) Through the analysis of the early broken teeth of the excavator slewing bearing replaced by data analysis, it is found that most of the broken teeth occurred in the upper half of the tooth width direction, and more than half of the broken surface and the upper end face of the gear teeth They intersect and form an included angle of about 45° to 60°. Even if the whole tooth falls off, the crack is caused by the expansion from top to bottom. The plastic deformation caused by the extrusion of the gear is also quite obvious, and the upper part is much more serious than the lower part. The width of the entire ring of the tooth groove changes to varying degrees, and the width of the tooth groove increases from the bottom to the top and from the root to the top.