Slewing ring failure form has two kinds, one is the raceway damage, the second is broken teeth, and the raceway damage accounted for the proportion of over 98%, so FRB Bearings said, the raceway quality is the core of the quality of slewing bearing, there are many factors influencing the quality of the slewing ring raceway.Among them, the raceway hardnesss, raceway hardener depth,raceway radius of curvatureand and aceway contact angle are undoubtedly the most important four influencing factors.They affect the quality of the raceway in different ways and determine the bearing capacity and service life of the slewing bearings.
Raceway hardness
The hardening hardness of the slewing bearing raceway has a great impact on its rated static capacity. The minimum hardness specified in the standard is HRC55, and the actual average quenching hardness is usually around HRC57. Therefore, the actual bearing capacity of most of the slewing bearing is higher than the theoretical value calculated according to HRC55.When the hardness is lower than HRC53, even if the safety factor of 1.2 is left, it is not safe to use. In particular, when the hardness is only HRC50, the safety factor of 1.7 is useless, which is very dangerous.Lack of hardness can easily cause the failure of slewing bearing, from the beginning of the pitting on the surface of the raceway to the end of collapse.
