What is the cause of the slewing ring damage?

The slewing ring will be overloaded due to its own problems in use, unreliable sealing equipment, inadequate maintenance, etc will cause premature damage to the slewing ring raceway and rolling elements. The following are several reasons for the slewing ring damage.

1.Slewing bearing rings broken

This situation often occurs on heavy-duty slewing rings. During use, a ring is broken from the middle, causing the slewing ring to be unusable. There are two reasons for this problem. One is the design problem, such as the raceway is too large, the mounting hole is too close to the inner and outer diameters, which causes the wall to be too thin and breaks when subjected to heavy loads. Another reason is the material problem. The material has sandwiches, cracks, defects and other problems that will cause the slewing bearing to break during use.

2.Slewing ring gears broken

The slewing ring gear broken is also a common phenomenon, especially for the slewing rings with quenched gears, there are more cases of broken gears, in this case, the gear quenching hardness is generally too high, causing the gear position to be too brittle, gears will be broken when subjected to large load or quenching cracks have appeared during quenching, the teeth will break quickly when used. Improper installation can also cause gear breakage. The gear of the slewing ring does not mesh well with the pinion, too tight, too loose, axis is not parallel, will cause gear break too.

3.The hardened layer of the slewing ring raceway falls off

The hardened layer of the slewing ring raceway falls off or fall blocks, and presents a concave-convex shape. This situation is generally caused by the channel quenching not being done well, and the surface hardness of the raceway is too low or uneven, high rolling element hardness, low raceway hardness, alternate layers of high hardness and low hardness are extruded under heavy load and cause peeling off, its characteristic is that the fall off is in the form of flakes or blocks and this kind of damage sometimes occurs at the junction of the raceway tempered soft area.

4.Rolling elements damage

During use, the steel balls or rollers may fall off or crack, causing damage to the slewing bearing. This situation is generally caused by using inferior and unqualified rolling elements for the slewing ring.

5.Slewing ring raceway wear

There are generally two reasons for slewing ring raceway wear : seal failure or lack of lubrication.

The slewing ring seals are damaged and not replaced in time, will cause dust, sand, dirt and other particles to enter the raceway, grinding the raceway and rolling elements, causing invisible metal to fall off, the falling metal powder will aggravate wear. In order to avoid this kind of problem, it is necessary to check the wear condition of the sealing rings and replace the severely worn sealing rings in time to prevent sand, dust and moisture from entering the raceway causing damage to the slewing ring.

When the slewing ring lacks grease, under the effect of heavy load, the friction between the rolling elements and the raceway will increase, and the rotation resistance will increase, resulting in inflexible rotation. If the slewing ring is short of oil for a long time, the slewing ring will be damaged or even scrapped.

U-TRSM hopes that everyone can be familiar with the common phenomena of slewing ring damage. When the slewing ring is damaged, you can analyze the cause of the damage, solve the problem in time, do daily maintenance of the slewing bearing to extend the slewing bearing service life.