What is a slewing ring bearing? What are the characteristics?

The slewing ring is a special bearing that can bear large axial load, radial load and overturning moment and other comprehensive loads at the same time. Under normal circumstances, the slewing bearing itself is equipped with mounting holes, lubricating oil holes and sealing devices, which can meet the different needs of various types of hosts working under various working conditions. 

On the other hand, the slewing bearing itself has the characteristics of compact structure, convenient guiding and rotation, simple installation and easy maintenance, etc., and is widely used in slewing devices such as lifting and transportation machinery, mining machinery, port machinery, medical equipment and military industry.

According to different structural types, slewing bearings can be divided into: four-point contact ball type, double-row angular contact ball type, cross cylindrical roller type three-row cylindrical roller combination type, etc. 

The above types of bearings are divided into different structures such as toothless type, external gear type and internal gear type according to whether they have teeth and the distribution of gears.

According to different structural characteristics, the slewing bearing can respectively meet the needs of the working host under various load conditions.

Structure type

Four-point contact ball slewing bearing

The single-row four-point contact ball bearing is generally composed of two races, with compact structure, light weight, four-point contact between the steel ball and the arc raceway, and can bear axial force, radial force and overturning moment at the same time. 

Construction machinery such as rotary conveyor, welding manipulator, small and medium-sized crane and excavator can be selected. The four-point contact ball slewing bearing has high dynamic load capacity.

Double row angular contact ball slewing bearing

The double-row angular contact ball slewing bearing has three races. The steel balls and spacers can be directly discharged into the upper and lower raceways. According to the stress conditions, the upper and lower steel balls with different diameters are arranged. 

This form of assembly is very convenient and can withstand large axial forces and overturning moments. The axial and radial dimensions of the double-row angular contact ball slewing bearing are relatively large and the structure is firm. It is especially suitable for tower cranes and truck cranes that require medium or larger diameters.

Cross Cylindrical Roller Slewing Ring

The single-row crossed cylindrical roller slewing bearing is generally composed of two races. It has compact structure, light weight, high manufacturing accuracy, small assembly clearance, and high requirements for installation accuracy. Bearing axial force, overturning moment and large radial force, it is widely used in lifting transportation, construction machinery and military products. 

The crossed cylindrical roller slewing bearing has high static load capacity, and the crossed cylindrical slewing bearing can make the bearing have greater support rigidity and higher rotation accuracy through its pre-interference.

The three-row cylindrical roller combined slewing bearing has three races, and the upper and lower and radial raceways are separated, so that the load of each row of rollers can be accurately determined. It can bear various loads at the same time, and is the one with the largest bearing capacity among the four products. The axial and radial dimensions are large and the structure is firm. 

It is especially suitable for heavy machinery requiring large diameters, such as bucket wheel excavators, wheeled Cranes, ship cranes, molten steel turntables and large-tonnage trucks. 

The three-row cylindrical roller combined slewing bearing guides the improvement of the bearing capacity to the height direction of the bearing, and various loads are borne by different raceways and roller groups, so under the same stress conditions, the diameter of the bearing can be adjusted. 

It is greatly reduced, so it has the characteristics of making the host more compact, and it is a slewing bearing with high bearing capacity.