The slewing ring is a large bearing that can bear comprehensive loads, and can bear large axial and radial loads and overturning moments at the same time. Slewing ring bearings generally have mounting holes, internal or external gears, lubricating oil holes and sealing devices, so that the design of the main engine can be compact, easy to guide, and easy to maintain. The slewing ring bearings include four-point contact ball bearings with no gears, external gears and internal gears, double-row angular contact ball bearings, crossed cylindrical roller bearings, crossed tapered roller bearings and three-row cylindrical roller composite bearings. series. The four-point contact ball slewing bearing has high static load capacity, the crossed cylindrical roller has high dynamic load capacity, and the pre-interference of the crossed tapered roller bearing can make the bearing have greater support rigidity and rotation accuracy. The three-row cylindrical roller combined bearing leads to the height of the bearing due to the improvement of the bearing capacity, and various forces are borne by different raceways. Therefore, under the same force, the diameter of the bearing can be greatly reduced, so it has the feature of making the main engine more compact. It is a slewing ring bearing with high bearing capacity.
The three-row roller slewing bearing has three separate upper and lower races and radial raceways, so that the load of each row of rollers can be accurately determined and can bear various loads at the same time. It has the largest bearing capacity among the four products, and the shaft and radial dimensions are large and the structure is firm. The three-row roller slewing bearing is especially suitable for heavy machinery requiring larger diameters, such as bucket wheel excavators, wheeled cranes, marine cranes, ladle slewing and large tonnage truck cranes.
The double row slewing bearing has three races, and the steel balls and spacers can be directly discharged into the upper and lower raceways. According to the stress conditions, two rows of steel balls with different diameters are arranged. This kind of open assembly is very convenient, and the bearing angle of the upper and lower arc raceways is 90°, which can bear a large axial force and tipping moment. When the radial force is greater than 0.1 times the axial force, the raceway must be specially designed. The axial and radial dimensions of the double-row ball slewing bearing are relatively large, and the structure is firm, especially suitable for loading and unloading machinery such as tower cranes and truck cranes that require a medium diameter or above.
The single cross roller slewing bearing consists of two races, with compact structure, light weight, high manufacturing precision, small assembly clearance, and high requirements for installation precision. The rollers are arranged in a 1:1 cross. It can withstand axial force, large radial force and tipping moment at the same time, and is widely used in lifting transportation, construction machinery and military products.
The single-row four point contact ball slewing bearing is 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 tipping moment at the same time. It can be used in construction machinery such as slew conveyors, welding operators, small and medium-sized cranes and excavators.