Double Row 8 Point Contact Ball Slew Bearings

The double-row ball slewing bearing is mainly composed of an inner ring, an outer ring, two rows of rolling elements (steel balls), a spacer or a cage and a sealing device. The raceway usually adopts a peach-shaped groove, and the surface hardening treatment is performed by medium frequency. The surface hardness can reach HRC55-60, and the depth of the hardened layer can reach 3~5mm. The single raceway and the steel ball are loaded in a four-point contact manner. The curvature radius of the raceway is accurately calculated to ensure that the rolling element can roll smoothly during the rotation process, reducing rolling resistance and energy loss. Its inner and outer rings usually have multiple mounting holes for fixing on the equipment. The rolling element rolls between the inner and outer rings under the guidance of the cage or the spacer to ensure smooth rotation. Under the same inner and outer diameter installation dimensions, the load of the eight-point contact ball slewing bearing is 70-80% higher than that of the four-point contact ball slewing bearing.

Double-row ball slewing bearings are divided into toothless, external and internal gear structures. The tooth surface can be strengthened by heat treatment methods such as tooth surface scanning quenching, tooth surface and tooth root medium frequency quenching or matrix hardness improvement according to different working conditions. Different pinions can be matched according to different working conditions.

Double-row ball slewing bearings can withstand large axial loads, radial loads and overturning moments at the same time, with a higher safety factor. They are widely used in medium and large cranes, mining equipment, excavators and other mechanical equipment.

Double Row 8 Point Contact Ball Slew Bearing without Gear

External Gear 8 Point Contact Ball Slew Bearing

Internal Gear 8 Point Contact Ball Slew Bearing